Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Jack, Its all clear now, thanks! I doubt that the $125 filters that I used are still available at that price; remember that was 14 years ago Darn time passes fast doesn't it? rflink's filter at $325, tower mountable, sounds like a winning solution, that I need to try. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Jack Unger" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Monday, October 30, 2006 10:56 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Tom, Please see my answers inline, below. Tom DeReggi wrote: Jack, That is helpful information, and helps explain the situation, thank you. However, I'm not sure that I understand how the response answers my primary confusion, "how to tell whether the interference is caused by me or them". Inserting a filter inline, will of course tell me if my interference can or can not be cured with a bandpass filter. Whether it was the other party bleeding outside of its channels, or power overloading my receiver, the bandpass filter would help reduce either problem, wouldn't it? If a paging transmitter is transmitting spurious signals down below 928 MHz, a bandpass filter won't help but if the paging system is NOT transmitting off-frequency but is overloading your receiver then the bandpass filter WILL help. (reduction of power and reduction of bandwidth bleedover). So what it sounds like is, an installer should always have a filter on-hand to insert and test with at time of installation, to see if it helps? That's a good idea. The installer should check throughput from a distant client with and without the filter. Basically meaning, who cares who the culprit is, if their is a way to just cure the problem. Knowing the "culprit" is important in order to troubleshoot the problem cost effectively; per my previous (and above) explanations. Again, if the paging system is transmitting outside it's authorized frequency band, the bandpass filter will NOT help. Where my question specifically related to Trango was Many Trango users had installed filters to try and stop the interference from paging companies, and it did not help. Using the correct type of bandpass filter is also important. There are narrow-band (single channel) filters and whole-band (902-928 MHz) filters. I don't know what type of filters the "many Trango installers" tried so I'm unable to provide further insight into why they got the results they did. Normally, this makes no sense, because in theory the filters would always help. One of Trango's benefits were that it in fact had quality 900 filters installed already to help reduce interference. It is one of the features that it had above Canopy, Waverider, and OEM wifi products. Maybe the internal filters weren't good enough to reduce the overloading. And its not always cheap, to find out wether the filter would help. It sometimes means making a second climb to 500 feet, or bringing power up 500feet for the test, that did not yet have Coax or a second DC power feed. Not difficult to do, but clearly an added cost for something that may or may not improve above what Trango already has built-in, based on other's experience. Unfortunately, there's no easy way to predict if a filter will help - other than trying it. It would help to do an interference survey before selecting a tower site. If there is a 929 MHz paging transmitter on a tower (an the interference survey) would reveal this, then it is wise to: 1. Stay as far away as possible on that tower, or 2. Don't go on that tower, or 3. Plan to use a good bandpass or cavity filter. This is just applying basic engineering skills and/or good common sense. What would be interesting is learning more about the filter that you previously procured and/or how to make them. At $125 each, I'd have a slew of them laying around for using on the fly. At $125, it would be cheap enough to istall on every CPE radio as well, if needed. But I haven't found them for less than $450, and they typically had closer to 3 db power reduction on their spec sheets. And is it possible to build a passive Filter that does not require additional electric power? I doubt that the $125 filters that I used are still available at that price; remember that was 14 years ago. Here is a much better filter that is available today and it even has an outdoor weatherproof case. http://www.rflinx.com/products/filters/900/bpfx/ Bandpass filters are passive. They do not require electical power. Also, it's likely a waste of money (as I mentioned earlier) to use these on the CPE end unless the CPE end is close to a cell tower or paging tower. These bandpass filters are most needed on the AP - if the AP is near (or on) a cell/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Tom, Good summary. jack Tom DeReggi wrote: John, Helpful post! In summary of this thread, I guess the message I'm getting is, there is no substitution for the right tool for the job. And its clear that an analyzer is the correct tool, to truely learn the characteristics of your RF colocated neighbor, without risk of false assumptions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "John Scrivner" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Saturday, October 28, 2006 12:12 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Good info Jack. In a past life I was a headend tech in the cable television industry. and I also performed signal egress and ingress troubleshooting using a Hewlett Packard 8591B analyzer. I spent a few thousand hours on this tool and learned much about spectrum analysis at that time. Here is some info for some of those out there who may be new to spectrum analysis: There is something that can make these paging transmitters appear to be bleeding over into the ISM bands when in fact they may not be. The setting on the analyzer is called "resolution bandwidth". This setting takes all power within a given bandspace and averages it together as it sweeps across the screen. The wider this setting is the fewer bumps you see on the screen. The trace will smooth out as you increase this setting because it is averaging power within a wider space of spectrum. This has the added effect of making a "loud" carrier appear to cover a wider space than it actually does and can cause you to believe that a paging or other carrier is bleeding over into the ISM band. On the contrary, narrowing the resolution bandwidth will show more accurate representation of actual power in a given bandspace but is slower to scan on most analyzers and produces a very sporadic display. If you are looking for narrowband or adjacent channel interference into your band then a narrow resolution bandwidth will be required. If you are wanting to take a RSSI reading of your own carrier then a wider resolution bandwidth will be required. Resolution bandwidth is something you should learn to use and understand if you want to get more from your work. It is an important part of spectrum analysis. If you want to see how good an analyzer is then look at how low the resolution bandwidth setting will allow. For our work a minimum resolution bandwidth of about 100kHz is probably all you will ever need. Also run it at its lowest resolution bandwidth and see how long it takes to scan across the screen. If you are comparing multiple analyzers make sure you always use the same span setting (difference between upper and lower frequency on display). A narrower span will display a narrow resolution bandwidth much faster. Better analyzers will have a wide range of resolution bandwidth settings and will show a sharp, clean display in any setting. Learning to use a spectrum analyzer can seem daunting at first glance. Do not let this intimidate you. You can learn to use this and get meaningful information from it if you give it a try. You will not break the analyzer by experimenting with it. If the unit you are using has knobs and you had it set by someone previously then just take notes of where they are set and then experiment with the unit. The most important things to master are start frequency, stop frequency, span, center frequency, reference level, attenuation, resolution bandwidth. Anything else you learn is good to know but not as much as what I just outlined here. If anyone here is working with an analyzer and does not know what any of those things mean then feel free to ask here onlist (or offlist if you would prefer to not tell others you do not know):-) Scriv Jack Unger wrote: Tom, Yes, their gear (the paging stuff) not only costs more but their transmitters spurious emissions have to remain low or the paging company risks being fined by the FCC. Sure, a transmitter can malfunction once in a while and cause interference to the ISM band but this is not a common occurance. Our gear has receivers where the manufacturing cost is quite low. There may be $50 worth of parts in the receiver section of an AP. The vendors typically do not spend a lot of money on components that would raise the cost of their equipment and make it non-competitive such as adding expensive filters to reduce the overloading problems that only a minority of WISPs may ever experience. Similarly, the new cars that people buy don't come with the most expensive tires as standard equipment because most people would never notice a difference or be willing to pay more for the premium tires. I started deploying 900 MHz bridges in 1993 and 900 MHz APs (yes, for WISP service) in 1995. I used Lucent "Wavelan" cards in those systems. Whe
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
John, Helpful post! In summary of this thread, I guess the message I'm getting is, there is no substitution for the right tool for the job. And its clear that an analyzer is the correct tool, to truely learn the characteristics of your RF colocated neighbor, without risk of false assumptions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "John Scrivner" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Saturday, October 28, 2006 12:12 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Good info Jack. In a past life I was a headend tech in the cable television industry. and I also performed signal egress and ingress troubleshooting using a Hewlett Packard 8591B analyzer. I spent a few thousand hours on this tool and learned much about spectrum analysis at that time. Here is some info for some of those out there who may be new to spectrum analysis: There is something that can make these paging transmitters appear to be bleeding over into the ISM bands when in fact they may not be. The setting on the analyzer is called "resolution bandwidth". This setting takes all power within a given bandspace and averages it together as it sweeps across the screen. The wider this setting is the fewer bumps you see on the screen. The trace will smooth out as you increase this setting because it is averaging power within a wider space of spectrum. This has the added effect of making a "loud" carrier appear to cover a wider space than it actually does and can cause you to believe that a paging or other carrier is bleeding over into the ISM band. On the contrary, narrowing the resolution bandwidth will show more accurate representation of actual power in a given bandspace but is slower to scan on most analyzers and produces a very sporadic display. If you are looking for narrowband or adjacent channel interference into your band then a narrow resolution bandwidth will be required. If you are wanting to take a RSSI reading of your own carrier then a wider resolution bandwidth will be required. Resolution bandwidth is something you should learn to use and understand if you want to get more from your work. It is an important part of spectrum analysis. If you want to see how good an analyzer is then look at how low the resolution bandwidth setting will allow. For our work a minimum resolution bandwidth of about 100kHz is probably all you will ever need. Also run it at its lowest resolution bandwidth and see how long it takes to scan across the screen. If you are comparing multiple analyzers make sure you always use the same span setting (difference between upper and lower frequency on display). A narrower span will display a narrow resolution bandwidth much faster. Better analyzers will have a wide range of resolution bandwidth settings and will show a sharp, clean display in any setting. Learning to use a spectrum analyzer can seem daunting at first glance. Do not let this intimidate you. You can learn to use this and get meaningful information from it if you give it a try. You will not break the analyzer by experimenting with it. If the unit you are using has knobs and you had it set by someone previously then just take notes of where they are set and then experiment with the unit. The most important things to master are start frequency, stop frequency, span, center frequency, reference level, attenuation, resolution bandwidth. Anything else you learn is good to know but not as much as what I just outlined here. If anyone here is working with an analyzer and does not know what any of those things mean then feel free to ask here onlist (or offlist if you would prefer to not tell others you do not know):-) Scriv Jack Unger wrote: Tom, Yes, their gear (the paging stuff) not only costs more but their transmitters spurious emissions have to remain low or the paging company risks being fined by the FCC. Sure, a transmitter can malfunction once in a while and cause interference to the ISM band but this is not a common occurance. Our gear has receivers where the manufacturing cost is quite low. There may be $50 worth of parts in the receiver section of an AP. The vendors typically do not spend a lot of money on components that would raise the cost of their equipment and make it non-competitive such as adding expensive filters to reduce the overloading problems that only a minority of WISPs may ever experience. Similarly, the new cars that people buy don't come with the most expensive tires as standard equipment because most people would never notice a difference or be willing to pay more for the premium tires. I started deploying 900 MHz bridges in 1993 and 900 MHz APs (yes, for WISP service) in 1995. I used Lucent "Wavelan" cards in those systems. Whenever I was located within about 1/3 of a mile from a
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Tom, Please see my answers inline, below. Tom DeReggi wrote: Jack, That is helpful information, and helps explain the situation, thank you. However, I'm not sure that I understand how the response answers my primary confusion, "how to tell whether the interference is caused by me or them". Inserting a filter inline, will of course tell me if my interference can or can not be cured with a bandpass filter. Whether it was the other party bleeding outside of its channels, or power overloading my receiver, the bandpass filter would help reduce either problem, wouldn't it? If a paging transmitter is transmitting spurious signals down below 928 MHz, a bandpass filter won't help but if the paging system is NOT transmitting off-frequency but is overloading your receiver then the bandpass filter WILL help. (reduction of power and reduction of bandwidth bleedover). So what it sounds like is, an installer should always have a filter on-hand to insert and test with at time of installation, to see if it helps? That's a good idea. The installer should check throughput from a distant client with and without the filter. Basically meaning, who cares who the culprit is, if their is a way to just cure the problem. Knowing the "culprit" is important in order to troubleshoot the problem cost effectively; per my previous (and above) explanations. Again, if the paging system is transmitting outside it's authorized frequency band, the bandpass filter will NOT help. Where my question specifically related to Trango was Many Trango users had installed filters to try and stop the interference from paging companies, and it did not help. Using the correct type of bandpass filter is also important. There are narrow-band (single channel) filters and whole-band (902-928 MHz) filters. I don't know what type of filters the "many Trango installers" tried so I'm unable to provide further insight into why they got the results they did. Normally, this makes no sense, because in theory the filters would always help. One of Trango's benefits were that it in fact had quality 900 filters installed already to help reduce interference. It is one of the features that it had above Canopy, Waverider, and OEM wifi products. Maybe the internal filters weren't good enough to reduce the overloading. And its not always cheap, to find out wether the filter would help. It sometimes means making a second climb to 500 feet, or bringing power up 500feet for the test, that did not yet have Coax or a second DC power feed. Not difficult to do, but clearly an added cost for something that may or may not improve above what Trango already has built-in, based on other's experience. Unfortunately, there's no easy way to predict if a filter will help - other than trying it. It would help to do an interference survey before selecting a tower site. If there is a 929 MHz paging transmitter on a tower (an the interference survey) would reveal this, then it is wise to: 1. Stay as far away as possible on that tower, or 2. Don't go on that tower, or 3. Plan to use a good bandpass or cavity filter. This is just applying basic engineering skills and/or good common sense. What would be interesting is learning more about the filter that you previously procured and/or how to make them. At $125 each, I'd have a slew of them laying around for using on the fly. At $125, it would be cheap enough to istall on every CPE radio as well, if needed. But I haven't found them for less than $450, and they typically had closer to 3 db power reduction on their spec sheets. And is it possible to build a passive Filter that does not require additional electric power? I doubt that the $125 filters that I used are still available at that price; remember that was 14 years ago. Here is a much better filter that is available today and it even has an outdoor weatherproof case. http://www.rflinx.com/products/filters/900/bpfx/ Bandpass filters are passive. They do not require electical power. Also, it's likely a waste of money (as I mentioned earlier) to use these on the CPE end unless the CPE end is close to a cell tower or paging tower. These bandpass filters are most needed on the AP - if the AP is near (or on) a cell/paging tower. jack Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Jack Unger" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Saturday, October 28, 2006 1:03 AM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Tom, Yes, their gear (the paging stuff) not only costs more but their transmitters spurious emissions have to remain low or the paging company risks being fined by the FCC. Sure, a transmitter can malfunction once in a while and cause interference to the ISM band but
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Jack, That is helpful information, and helps explain the situation, thank you. However, I'm not sure that I understand how the response answers my primary confusion, "how to tell whether the interference is caused by me or them". Inserting a filter inline, will of course tell me if my interference can or can not be cured with a bandpass filter. Whether it was the other party bleeding outside of its channels, or power overloading my receiver, the bandpass filter would help reduce either problem, wouldn't it? (reduction of power and reduction of bandwidth bleedover). So what it sounds like is, an installer should always have a filter on-hand to insert and test with at time of installation, to see if it helps? Basically meaning, who cares who the culprit is, if their is a way to just cure the problem. Where my question specifically related to Trango was Many Trango users had installed filters to try and stop the interference from paging companies, and it did not help. Normally, this makes no sense, because in theory the filters would always help. One of Trango's benefits were that it in fact had quality 900 filters installed already to help reduce interference. It is one of the features that it had above Canopy, Waverider, and OEM wifi products. And its not always cheap, to find out wether the filter would help. It sometimes means making a second climb to 500 feet, or bringing power up 500feet for the test, that did not yet have Coax or a second DC power feed. Not difficult to do, but clearly an added cost for something that may or may not improve above what Trango already has built-in, based on other's experience. What would be interesting is learning more about the filter that you previously procured and/or how to make them. At $125 each, I'd have a slew of them laying around for using on the fly. At $125, it would be cheap enough to istall on every CPE radio as well, if needed. But I haven't found them for less than $450, and they typically had closer to 3 db power reduction on their spec sheets. And is it possible to build a passive Filter that does not require additional electric power? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Jack Unger" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Saturday, October 28, 2006 1:03 AM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Tom, Yes, their gear (the paging stuff) not only costs more but their transmitters spurious emissions have to remain low or the paging company risks being fined by the FCC. Sure, a transmitter can malfunction once in a while and cause interference to the ISM band but this is not a common occurance. Our gear has receivers where the manufacturing cost is quite low. There may be $50 worth of parts in the receiver section of an AP. The vendors typically do not spend a lot of money on components that would raise the cost of their equipment and make it non-competitive such as adding expensive filters to reduce the overloading problems that only a minority of WISPs may ever experience. Similarly, the new cars that people buy don't come with the most expensive tires as standard equipment because most people would never notice a difference or be willing to pay more for the premium tires. I started deploying 900 MHz bridges in 1993 and 900 MHz APs (yes, for WISP service) in 1995. I used Lucent "Wavelan" cards in those systems. Whenever I was located within about 1/3 of a mile from a cell site (with colocated 929 MHz and 930 MHz paging) I had to add an external bandpass filter between the antenna and the antenna connector on the Wavelan card. Until I did this, I could not get full throughput (which was about 1.3 Mbps in those days) through the card. The bandpass filter would clear up the problem every time. Those filters weren't even that strong - only about 6 dB of attenuation at 900 MHz and at 930 MHz (even less - maybe 5 dB at 929 MHz) but it was enough to protect the Wavelan card's receiver from being overloaded. These bandpass filters were made by a 3rd-party source and custom tuned by me in a calibration lab. My filter cost was $125 each and they were not weatherproof so I mounted them indoors. The inband attenuation was aboat 1 or 1.5 dB which was insignificant in light of the fact that the filters worked to eliminate the overloading and allow the AP to receive client signals up to 10 or 12 miles away. Regarding Trango - I have not verified the accuracy of their spectrum analysis tool but what you're seeing can be explained by one observation and one guestimation. The -20 dBm to -30 dBm signal indications above 929 MHz are likely fairly accurate. Nearby paging transmitters could easily be that loud. The fact that you're seeing signals down to 924 MHz or so could be explain
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
3rd-party source and custom tuned by me in a calibration lab. My filter cost was $125 each and they were not weatherproof so I mounted them indoors. The inband attenuation was aboat 1 or 1.5 dB which was insignificant in light of the fact that the filters worked to eliminate the overloading and allow the AP to receive client signals up to 10 or 12 miles away. Regarding Trango - I have not verified the accuracy of their spectrum analysis tool but what you're seeing can be explained by one observation and one guestimation. The -20 dBm to -30 dBm signal indications above 929 MHz are likely fairly accurate. Nearby paging transmitters could easily be that loud. The fact that you're seeing signals down to 924 MHz or so could be explained by the Trango receiver "front-end" (the first stage connected to the antenna) being overloaded by one or more nearby paging transmitters. When a receiver is overloaded, it generates "spurious" signals that are not really being transmitted on the frequency where they show up. The "spurs" are being generated inside the receiver itself as a consequence of the overloading. It's fairly easy to test to see if this is the case. Just insert a bandpass filter between the antenna and the antenna connector (assuming a connectorized AP). If the AP receiving distance and/or the throughput increases, you have just proved that overloading was a problem. You can also re-run the spectrum analysis tool and see if it no longer reports signals down to 924 MHz. It should now report that the non-WISP signals start around 929 MHz. I hope this explanation helps. jack Tom DeReggi wrote: Jack, That all sounds good, and it brings up a good point, that we are just as probable to be the culprit, not just the other guy. Besides, their gear costs more, right :-) However, what specific gear do you have experience with, on this issue, to support your comment? I'm not sure that I am knowledgable enough on the topic, to know for sure which side is the flaw, how would we tell? I use Trango 900. Trango's have a built-in specrum site survey tool, that also scans a bit lower and higher than the ISM edge. My comment was based on the fact that, when I do the site survey, I see signals in the neg 20-30 range, spanning from significantly above 930 down to mid portion of ISM channel 4 (924 or so). Have you verified the accuracy of the Trango tool, and how it reacts to this situation? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Jack Unger" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Friday, October 27, 2006 1:07 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen "Bleed over" implies that the paging system is transmitting a signal that is too wide. This is typically NOT the case. Our rather inexpensive WISP AP receivers do not have adequate selectivity to reject strong nearby signals. In other words, it's our equipment problem not their equipment problem. Also, WISP subscriber sites, unless located right under a paging/cellular tower aren't close enough to be overloaded by paging/cellular so they would not need the bandpass filter. Only our APs which are located near paging/cellular towers should need the bandpass filters. jack Larry Yunker wrote: While filters can help, the problem that I see is that filters are: 1) expensive and 2) bulky. Last time I checked, a cavity filter for the 902-928 range was roughly $300-$400. I don't see it being practical to install one of these at every customer site! Cavity filters are fine for your broadcast sites, but that is of little help when the 900Mhz paging systems bleed over so much that they "deafen" the subscriber radios. - Larry ----- Original Message ----- From: "Mike Cowan" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 7:32 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have b
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Tom, Yes, their gear (the paging stuff) not only costs more but their transmitters spurious emissions have to remain low or the paging company risks being fined by the FCC. Sure, a transmitter can malfunction once in a while and cause interference to the ISM band but this is not a common occurance. Our gear has receivers where the manufacturing cost is quite low. There may be $50 worth of parts in the receiver section of an AP. The vendors typically do not spend a lot of money on components that would raise the cost of their equipment and make it non-competitive such as adding expensive filters to reduce the overloading problems that only a minority of WISPs may ever experience. Similarly, the new cars that people buy don't come with the most expensive tires as standard equipment because most people would never notice a difference or be willing to pay more for the premium tires. I started deploying 900 MHz bridges in 1993 and 900 MHz APs (yes, for WISP service) in 1995. I used Lucent "Wavelan" cards in those systems. Whenever I was located within about 1/3 of a mile from a cell site (with colocated 929 MHz and 930 MHz paging) I had to add an external bandpass filter between the antenna and the antenna connector on the Wavelan card. Until I did this, I could not get full throughput (which was about 1.3 Mbps in those days) through the card. The bandpass filter would clear up the problem every time. Those filters weren't even that strong - only about 6 dB of attenuation at 900 MHz and at 930 MHz (even less - maybe 5 dB at 929 MHz) but it was enough to protect the Wavelan card's receiver from being overloaded. These bandpass filters were made by a 3rd-party source and custom tuned by me in a calibration lab. My filter cost was $125 each and they were not weatherproof so I mounted them indoors. The inband attenuation was aboat 1 or 1.5 dB which was insignificant in light of the fact that the filters worked to eliminate the overloading and allow the AP to receive client signals up to 10 or 12 miles away. Regarding Trango - I have not verified the accuracy of their spectrum analysis tool but what you're seeing can be explained by one observation and one guestimation. The -20 dBm to -30 dBm signal indications above 929 MHz are likely fairly accurate. Nearby paging transmitters could easily be that loud. The fact that you're seeing signals down to 924 MHz or so could be explained by the Trango receiver "front-end" (the first stage connected to the antenna) being overloaded by one or more nearby paging transmitters. When a receiver is overloaded, it generates "spurious" signals that are not really being transmitted on the frequency where they show up. The "spurs" are being generated inside the receiver itself as a consequence of the overloading. It's fairly easy to test to see if this is the case. Just insert a bandpass filter between the antenna and the antenna connector (assuming a connectorized AP). If the AP receiving distance and/or the throughput increases, you have just proved that overloading was a problem. You can also re-run the spectrum analysis tool and see if it no longer reports signals down to 924 MHz. It should now report that the non-WISP signals start around 929 MHz. I hope this explanation helps. jack Tom DeReggi wrote: Jack, That all sounds good, and it brings up a good point, that we are just as probable to be the culprit, not just the other guy. Besides, their gear costs more, right :-) However, what specific gear do you have experience with, on this issue, to support your comment? I'm not sure that I am knowledgable enough on the topic, to know for sure which side is the flaw, how would we tell? I use Trango 900. Trango's have a built-in specrum site survey tool, that also scans a bit lower and higher than the ISM edge. My comment was based on the fact that, when I do the site survey, I see signals in the neg 20-30 range, spanning from significantly above 930 down to mid portion of ISM channel 4 (924 or so). Have you verified the accuracy of the Trango tool, and how it reacts to this situation? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Jack Unger" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Friday, October 27, 2006 1:07 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen "Bleed over" implies that the paging system is transmitting a signal that is too wide. This is typically NOT the case. Our rather inexpensive WISP AP receivers do not have adequate selectivity to reject strong nearby signals. In other words, it's our equipment problem not their equipment problem. Also, WISP subscriber sites, unless located right under a paging/cellular tower aren't close enough to be overloaded by paging/cellular
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Jack, That all sounds good, and it brings up a good point, that we are just as probable to be the culprit, not just the other guy. Besides, their gear costs more, right :-) However, what specific gear do you have experience with, on this issue, to support your comment? I'm not sure that I am knowledgable enough on the topic, to know for sure which side is the flaw, how would we tell? I use Trango 900. Trango's have a built-in specrum site survey tool, that also scans a bit lower and higher than the ISM edge. My comment was based on the fact that, when I do the site survey, I see signals in the neg 20-30 range, spanning from significantly above 930 down to mid portion of ISM channel 4 (924 or so). Have you verified the accuracy of the Trango tool, and how it reacts to this situation? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Jack Unger" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Friday, October 27, 2006 1:07 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen "Bleed over" implies that the paging system is transmitting a signal that is too wide. This is typically NOT the case. Our rather inexpensive WISP AP receivers do not have adequate selectivity to reject strong nearby signals. In other words, it's our equipment problem not their equipment problem. Also, WISP subscriber sites, unless located right under a paging/cellular tower aren't close enough to be overloaded by paging/cellular so they would not need the bandpass filter. Only our APs which are located near paging/cellular towers should need the bandpass filters. jack Larry Yunker wrote: While filters can help, the problem that I see is that filters are: 1) expensive and 2) bulky. Last time I checked, a cavity filter for the 902-928 range was roughly $300-$400. I don't see it being practical to install one of these at every customer site! Cavity filters are fine for your broadcast sites, but that is of little help when the 900Mhz paging systems bleed over so much that they "deafen" the subscriber radios. - Larry - Original Message - From: "Mike Cowan" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 7:32 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband Mike Cowan Wireless Connections A Division of ACC 166 Milan Ave Norwalk, OH 44857 419-660-6100 [EMAIL PROTECTED] www.wirelessconnections.net -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- Jack Unger ([EMAIL PROTECTED]) - President, Ask-Wi.Com, Inc. Serving the License-Free Wireless Industry Since 1993 Author of the WISP Handbook - "Deploying License-Free Wireless WANs" True Vendor-Neutral WISP Consulting-Training-Troubleshooting Newsletters Downloadable from http://ask-wi.com/newsletters.html Phone (VoIP Over Broadband Wireless) 818-227-4220 www.ask-wi.com -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
I concur. When a 900 MHz access point (AP) is located "near" a high-power paging (or other high-power) transmitter then a bandpass filter is "cheap insurance" to avoid or minimize the AP receiver "desensing" (overload) that the high-power transmitter may cause. It's impossible to know in advance how near a high-power transmitter is "too near". It depends on the AP receiver selectivity, the power of the nearby transmitter, the antenna patterns, the separation distance and the strength of the incoming signals from the WISP clients. Bandpass filters will help. Physically moving further away from the high-power transmitter will also help. jack P.S. - This is discussed on page 258 of my book. John Scrivner wrote: If you have an adjacent channel carrier which is running hundreds of watts of power then you may not have a choice of whether to use the bandpass filter or not. Your system may not operate in the upper part of the 900 MHz band. What happens is that the adjacent carrier will "swamp" your receiver and your base station will essentially become deaf to your own, much quieter, client radios. The bandpass filter is the sole remedy to this. I think many people use filters by default because they do little harm to your system performance and may mean the difference between your system working or completely failing in the presence of higher-powered adjacent carriers. I currently run Waverider 900 MHz systems and because of this I may have a system which is more sensitive to adjacent carrier swamping than other platforms. I simply do not know about other platforms to say one way or another. I believe Charles has tested several 900 MHz platforms and may be able to expand on this discussion. It is important to note that he may have a bias toward Canopy as he now sells that platform. I can only assume that his testing may have led him, in part, to this platform choice for 900 MHz systems. Care to share your thoughts Charles? If anyone out there has any past experience with swamped 900 MHJz receivers, bandpass filters, different 900 MHz platforms, etc. then please share your thoughts about the use/need for bandpass filters. I would like to know more myself. Scriv Larry Yunker wrote: While filters can help, the problem that I see is that filters are: 1) expensive and 2) bulky. Last time I checked, a cavity filter for the 902-928 range was roughly $300-$400. I don't see it being practical to install one of these at every customer site! Cavity filters are fine for your broadcast sites, but that is of little help when the 900Mhz paging systems bleed over so much that they "deafen" the subscriber radios. - Larry - Original Message - From: "Mike Cowan" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 7:32 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband Mike Cowan Wireless Connections A Division of ACC 166 Milan Ave Norwalk, OH 44857 419-660-6100 [EMAIL PROTECTED] www.wirelessconnections.net -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- Jack Unger ([EMAIL PROTECTED]) - President, Ask-Wi.Com, Inc. Serving the License-Free Wireless Industry Since 1993 Author of the WISP Handbook - "Deploying License-Free Wireless WANs" True Vendor-Neutral WISP Consulting-Training-Troubleshooting Newsletters Downloadable from http://ask-wi.com/newsletters.html Phone (VoIP Over Broadband Wireless) 818-227-4220 www.ask-wi.com -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
"Bleed over" implies that the paging system is transmitting a signal that is too wide. This is typically NOT the case. Our rather inexpensive WISP AP receivers do not have adequate selectivity to reject strong nearby signals. In other words, it's our equipment problem not their equipment problem. Also, WISP subscriber sites, unless located right under a paging/cellular tower aren't close enough to be overloaded by paging/cellular so they would not need the bandpass filter. Only our APs which are located near paging/cellular towers should need the bandpass filters. jack Larry Yunker wrote: While filters can help, the problem that I see is that filters are: 1) expensive and 2) bulky. Last time I checked, a cavity filter for the 902-928 range was roughly $300-$400. I don't see it being practical to install one of these at every customer site! Cavity filters are fine for your broadcast sites, but that is of little help when the 900Mhz paging systems bleed over so much that they "deafen" the subscriber radios. - Larry - Original Message - From: "Mike Cowan" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 7:32 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband Mike Cowan Wireless Connections A Division of ACC 166 Milan Ave Norwalk, OH 44857 419-660-6100 [EMAIL PROTECTED] www.wirelessconnections.net -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- Jack Unger ([EMAIL PROTECTED]) - President, Ask-Wi.Com, Inc. Serving the License-Free Wireless Industry Since 1993 Author of the WISP Handbook - "Deploying License-Free Wireless WANs" True Vendor-Neutral WISP Consulting-Training-Troubleshooting Newsletters Downloadable from http://ask-wi.com/newsletters.html Phone (VoIP Over Broadband Wireless) 818-227-4220 www.ask-wi.com -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
I'd originally written: The preponderence of NexTel channels are in the private land mobile 806-821/850-865 conventional / trunking band, and a small percentage in the 902-906 trunking band. ... I am most likely off on the numeric band I sure was [numerically off - that is]. What's known as the '900' trunking band runs from 896-902. I was only correct that it is *below* the 900 ISM band, and that it is only 12.5kHz channelized. rwf wrote: Just so we all know where you are coming from and in the interest of Full Disclosure, please tell us your involvement in the Dialcall/Nextel/Motorola/IDEN endeavor- specifically any vested interest in the technology (hint- Patents). Concerned that I might be some company shill? No need. I'd be happy to provide full disclosure. I left Moto about 4 yrs ago. I did some of the original work on Motorola's FCC comments to FleetCall's waiver request back in 92, but never worked in iDEN development. None of my patents are specific to iDEN technology, but I'd be flattered if you had looked them up. I've no vested interest in any of them anyway (all patents rights while employed at Moto are assigned to Moto, not the inventors). I've no vested interest in NexTel. As close as I get is my neighbor is a NexTel employee in sales ... does that count? Personally, I never liked or used NexTel service based on poor coverage / quality where I needed service. Hey, terms like '800' MHz, '900' MHz are *not one allocation*. Being from the radio manufacturing industry I'm acutely aware of how many different allocations are within these ranges. That's all, I just trying to be helpful in pointing out where the NexTel 900 trunking you mentioned is in relation to 900 MHz unlicensed ISM. And that I know that the iDEN served orders or magnitude more customers for NexTel than the original SMR license holders ever had, as FleetCall's original petition for waiver had correctly claimed. And that it's public knowledge where NexTel's new developments are targeted to other bands in conjunction with Sprint. chill, Rich - Original Message - From: "rwf" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Friday, October 27, 2006 2:24 AM Subject: RE: [WISPA] Sprint / Nextel to use 900mz for iDen Rich- Just so we all know where you are coming from and in the interest of Full Disclosure, please tell us your involvement in the Dialcall/Nextel/Motorola/IDEN endeavor- specifically any vested interest in the technology (hint- Patents). -Original Message- Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I don't know what the beef is. FleetCall bought up in the vicinity of 100 trunking & SMR channels in each major metro almost 20 yrs ago. They claimed to the FCC that they could serve significantly more users than the typical 100 users/channel of the current early 90s analog technology. 100 channels at 100 users apiece serves only in the vicinity of 10,000 users. With the iDen technology they ultimately served almost half a million in the same geographic area with the same spectrum. So much for the "unneeded technology" assessment. Now that they're called NexTel, sure they continue adding whatever remaining licenses they can get their hands on, but the 800 and 900 Trunking and bands are land-locked (no room for expansion), so there's no new technology targeted to this band that I know of. Now that they're merged with Sprint, it's no secret where their new technology is targeted (WiMAX). Rich -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
I'd add two commments to Scriv's post... 1) The requirement may vary significantly on wether one is using a Omni or Sector. When using an Omni, a filter becomes the only method to solve the problem, since it can't be solved with Antenna isolation strategies (shielding/front to back). 2) Filters fit real nicely into WaveRider's product, since Waverider already have COAX fed antenna ports, and a ground base station unit, requiring Coax up the tower already. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "John Scrivner" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Friday, October 27, 2006 9:09 AM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen If you have an adjacent channel carrier which is running hundreds of watts of power then you may not have a choice of whether to use the bandpass filter or not. Your system may not operate in the upper part of the 900 MHz band. What happens is that the adjacent carrier will "swamp" your receiver and your base station will essentially become deaf to your own, much quieter, client radios. The bandpass filter is the sole remedy to this. I think many people use filters by default because they do little harm to your system performance and may mean the difference between your system working or completely failing in the presence of higher-powered adjacent carriers. I currently run Waverider 900 MHz systems and because of this I may have a system which is more sensitive to adjacent carrier swamping than other platforms. I simply do not know about other platforms to say one way or another. I believe Charles has tested several 900 MHz platforms and may be able to expand on this discussion. It is important to note that he may have a bias toward Canopy as he now sells that platform. I can only assume that his testing may have led him, in part, to this platform choice for 900 MHz systems. Care to share your thoughts Charles? If anyone out there has any past experience with swamped 900 MHJz receivers, bandpass filters, different 900 MHz platforms, etc. then please share your thoughts about the use/need for bandpass filters. I would like to know more myself. Scriv Larry Yunker wrote: While filters can help, the problem that I see is that filters are: 1) expensive and 2) bulky. Last time I checked, a cavity filter for the 902-928 range was roughly $300-$400. I don't see it being practical to install one of these at every customer site! Cavity filters are fine for your broadcast sites, but that is of little help when the 900Mhz paging systems bleed over so much that they "deafen" the subscriber radios. - Larry - Original Message - From: "Mike Cowan" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 7:32 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband Mike Cowan Wireless Connections A Division of ACC 166 Milan Ave Norwalk, OH 44857 419-660-6100 [EMAIL PROTECTED] www.wirelessconnections.net -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Cavity Filters create several additional problems 1) Assuming most filters are narrow individual channel widths... It takes away the benefit to move your Radio Freq Channel to stear around interference on the fly. 2) Assuming 1 Filter covers the full width of the Band... The filters add significant loss, 3-4 db, so channels 1,2,3 that may not need the filters get compromised, just to save channel 4. In this business every DB counts. 3) Most filters get installed on the ground, where they can easilly get power and not need water proofing, then requiring large COAX runs to create additional signal loss. However, assuming one has a tower mountable unit, Many CAT5 powered 900M Radios, have the Antenna's built in, with no Coax option to install the filter on. 4) What we found worked best was to use very high grade Sector antennas w/ higher front to back ratios and sharper cut offs (which is hard to accomplish with NLOS 900M, but are a couple brands that accomplish this). These antenna get rid of most of the AP side colocation interference, near equivellent to the filter. Although the filter did a bit better on AP side, it was counter-acted by reducing signal several DB, having negative effects on gaining the required signal based on interference and NLOS foliage degrading CPE signal. And of course combine this with good radios with built-in noise reduction. With that said, I'm not saying a filter can't help in all cases, thats what they were designed for, to help. My point is that the benefit starts to be diminished signifantly compared to the cost. This issue is overyly burdensome to the provider. So the last thing we want to see happen is it get re-created on lower bands of 900Mhz. (iDEN ?) As far as filters If someone wanted to buy one, its a more complicated task than one always realizes. Cavity filters, notch filters, saw filters, Custom built, etc, what to get, and where to buy? Do you have recommendations on which Cavity Filters to use, for outdoor tower mounting? Or do you use the ones that WaveRider sold? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Larry Yunker" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Friday, October 27, 2006 9:25 AM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen While filters can help, the problem that I see is that filters are: 1) expensive and 2) bulky. Last time I checked, a cavity filter for the 902-928 range was roughly $300-$400. I don't see it being practical to install one of these at every customer site! Cavity filters are fine for your broadcast sites, but that is of little help when the 900Mhz paging systems bleed over so much that they "deafen" the subscriber radios. - Larry - Original Message - From: "Mike Cowan" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 7:32 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband Mike Cowan Wireless Connections A Division of ACC 166 Milan Ave Norwalk, OH 44857 419-660-6100 [EMAIL PROTECTED] www.wirelessconnections.net -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
If you have an adjacent channel carrier which is running hundreds of watts of power then you may not have a choice of whether to use the bandpass filter or not. Your system may not operate in the upper part of the 900 MHz band. What happens is that the adjacent carrier will "swamp" your receiver and your base station will essentially become deaf to your own, much quieter, client radios. The bandpass filter is the sole remedy to this. I think many people use filters by default because they do little harm to your system performance and may mean the difference between your system working or completely failing in the presence of higher-powered adjacent carriers. I currently run Waverider 900 MHz systems and because of this I may have a system which is more sensitive to adjacent carrier swamping than other platforms. I simply do not know about other platforms to say one way or another. I believe Charles has tested several 900 MHz platforms and may be able to expand on this discussion. It is important to note that he may have a bias toward Canopy as he now sells that platform. I can only assume that his testing may have led him, in part, to this platform choice for 900 MHz systems. Care to share your thoughts Charles? If anyone out there has any past experience with swamped 900 MHJz receivers, bandpass filters, different 900 MHz platforms, etc. then please share your thoughts about the use/need for bandpass filters. I would like to know more myself. Scriv Larry Yunker wrote: While filters can help, the problem that I see is that filters are: 1) expensive and 2) bulky. Last time I checked, a cavity filter for the 902-928 range was roughly $300-$400. I don't see it being practical to install one of these at every customer site! Cavity filters are fine for your broadcast sites, but that is of little help when the 900Mhz paging systems bleed over so much that they "deafen" the subscriber radios. - Larry - Original Message - From: "Mike Cowan" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 7:32 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband Mike Cowan Wireless Connections A Division of ACC 166 Milan Ave Norwalk, OH 44857 419-660-6100 [EMAIL PROTECTED] www.wirelessconnections.net -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
While filters can help, the problem that I see is that filters are: 1) expensive and 2) bulky. Last time I checked, a cavity filter for the 902-928 range was roughly $300-$400. I don't see it being practical to install one of these at every customer site! Cavity filters are fine for your broadcast sites, but that is of little help when the 900Mhz paging systems bleed over so much that they "deafen" the subscriber radios. - Larry - Original Message - From: "Mike Cowan" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 7:32 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband Mike Cowan Wireless Connections A Division of ACC 166 Milan Ave Norwalk, OH 44857 419-660-6100 [EMAIL PROTECTED] www.wirelessconnections.net -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
RE: [WISPA] Sprint / Nextel to use 900mz for iDen
Rich- Just so we all know where you are coming from and in the interest of Full Disclosure, please tell us your involvement in the Dialcall/Nextel/Motorola/IDEN endeavor- specifically any vested interest in the technology (hint- Patents). -Original Message- Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I don't know what the beef is. FleetCall bought up in the vicinity of 100 trunking & SMR channels in each major metro almost 20 yrs ago. They claimed to the FCC that they could serve significantly more users than the typical 100 users/channel of the current early 90s analog technology. 100 channels at 100 users apiece serves only in the vicinity of 10,000 users. With the iDen technology they ultimately served almost half a million in the same geographic area with the same spectrum. So much for the "unneeded technology" assessment. Now that they're called NexTel, sure they continue adding whatever remaining licenses they can get their hands on, but the 800 and 900 Trunking and bands are land-locked (no room for expansion), so there's no new technology targeted to this band that I know of. Now that they're merged with Sprint, it's no secret where their new technology is targeted (WiMAX). Rich -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Filters fix this problem quite handily. We recommend one on every system needed or not. I don't see an issue here. Mike At 07:07 PM 10/26/2006, you wrote: ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband Mike Cowan Wireless Connections A Division of ACC 166 Milan Ave Norwalk, OH 44857 419-660-6100 [EMAIL PROTECTED] www.wirelessconnections.net -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
ISM 902-928. Exact band and Power limit is relevant. Currently, the top 25% of ISM 900 bandwidth (channel 4) is unusable, in MANY areas, due to blead over from 930 Licensed high power gear (500W). If the same thing were to occur at the lower portion of 900 ISM bandwdith, it could kill Channel 1 also, horribly effecting WISPs using unlicenced. They also may be requesting to use higher power on the actual ISM bands, argueing Public Safety is more important than unlicensed use. Iftheir request is granted, specifics should be lsited on how they are going to prevent interference with existing unlicensed band users. Remember that the goal may not only be to use the spectrum. They have benefit in killing off all the 900Mhz WISPs, that could compete with Sprint/Nextel Next generation WiMax type Licensed 700M-900M solutions. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rich Comroe" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 3:08 PM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen The preponderence of NexTel channels are in the private land mobile 806-821/850-865 conventional / trunking band, and a small percentage in the 902-906 trunking band. So I believe whatever '900' channels they have are *below* the 900 ISM band. I am most likely off on the numeric band limits. But there are IIRC 15MHz of 25KHz channels that they hold licenses among at 800 (and the separate reverse channels 45MHz higher), and only 4MHz of 12.5KHz channels at 900 (including both T&R, but I don't recall the T/R split there). Rich - Original Message - From: "Brian Webster" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 11:49 AM Subject: RE: [WISPA] Sprint / Nextel to use 900mz for iDen Before everyone gets in an uproar about this, has anyone looked in to the actual frequencies being used? I'm pretty sure Nextel has some licensed 900 MHz spectrum. I don't have time to dig around for the information but as I recall they do. I could be wrong. They certainly won't deploy an IDEN system in the unlicensed bandsCome on. They might however cause interference with unlicensed stuff in certain situations where you might be co-located on the same sites. From what I have read I think this is only going to be in selected East Coast cities anyway, and it's a band aid approach to the rebanding process. Thank You, Brian Webster www.wirelessmapping.com <http://www.wirelessmapping.com> -Original Message- From: John Scrivner [mailto:[EMAIL PROTECTED] Sent: Thursday, October 26, 2006 10:30 AM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I am not familiar with the terms you describe below and I am a bit confused. Can you break this down with a little more detail and explanation? I would like to understand this as I think it is very important for us to know what they are trying to do here in 900 MHz. Thank you, John Scrivner rwf wrote: Nextel has been buying up 900 MHz trunked systems for years now. Probably will do what they did to build their first ESMR (Nextel IDEN)- Take perfectly good systems off the air so they can drive the users to an unneeded tcchnology. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom DeReggi Sent: Wednesday, October 25, 2006 9:05 PM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I think this is definately something we need the answer to (What part of 900Mhz). What exactly is "Green Space"? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rick Smith" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Wednesday, October 25, 2006 4:38 PM Subject: [WISPA] Sprint / Nextel to use 900mz for iDen http://www.rcrnews.com/news.cms?newsId=27618 They don't say exact freq's except for the reference to "unlicensed"... R -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
The scare was that... Unlicensed was specifically mentioned. Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Brian Webster" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 12:49 PM Subject: RE: [WISPA] Sprint / Nextel to use 900mz for iDen Before everyone gets in an uproar about this, has anyone looked in to the actual frequencies being used? I'm pretty sure Nextel has some licensed 900 MHz spectrum. I don't have time to dig around for the information but as I recall they do. I could be wrong. They certainly won't deploy an IDEN system in the unlicensed bandsCome on. They might however cause interference with unlicensed stuff in certain situations where you might be co-located on the same sites. From what I have read I think this is only going to be in selected East Coast cities anyway, and it's a band aid approach to the rebanding process. Thank You, Brian Webster www.wirelessmapping.com <http://www.wirelessmapping.com> -Original Message- From: John Scrivner [mailto:[EMAIL PROTECTED] Sent: Thursday, October 26, 2006 10:30 AM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I am not familiar with the terms you describe below and I am a bit confused. Can you break this down with a little more detail and explanation? I would like to understand this as I think it is very important for us to know what they are trying to do here in 900 MHz. Thank you, John Scrivner rwf wrote: Nextel has been buying up 900 MHz trunked systems for years now. Probably will do what they did to build their first ESMR (Nextel IDEN)- Take perfectly good systems off the air so they can drive the users to an unneeded tcchnology. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom DeReggi Sent: Wednesday, October 25, 2006 9:05 PM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I think this is definately something we need the answer to (What part of 900Mhz). What exactly is "Green Space"? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rick Smith" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Wednesday, October 25, 2006 4:38 PM Subject: [WISPA] Sprint / Nextel to use 900mz for iDen http://www.rcrnews.com/news.cms?newsId=27618 They don't say exact freq's except for the reference to "unlicensed"... R -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
The preponderence of NexTel channels are in the private land mobile 806-821/850-865 conventional / trunking band, and a small percentage in the 902-906 trunking band. So I believe whatever '900' channels they have are *below* the 900 ISM band. I am most likely off on the numeric band limits. But there are IIRC 15MHz of 25KHz channels that they hold licenses among at 800 (and the separate reverse channels 45MHz higher), and only 4MHz of 12.5KHz channels at 900 (including both T&R, but I don't recall the T/R split there). Rich - Original Message - From: "Brian Webster" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 11:49 AM Subject: RE: [WISPA] Sprint / Nextel to use 900mz for iDen Before everyone gets in an uproar about this, has anyone looked in to the actual frequencies being used? I'm pretty sure Nextel has some licensed 900 MHz spectrum. I don't have time to dig around for the information but as I recall they do. I could be wrong. They certainly won't deploy an IDEN system in the unlicensed bandsCome on. They might however cause interference with unlicensed stuff in certain situations where you might be co-located on the same sites. From what I have read I think this is only going to be in selected East Coast cities anyway, and it's a band aid approach to the rebanding process. Thank You, Brian Webster www.wirelessmapping.com <http://www.wirelessmapping.com> -Original Message- From: John Scrivner [mailto:[EMAIL PROTECTED] Sent: Thursday, October 26, 2006 10:30 AM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I am not familiar with the terms you describe below and I am a bit confused. Can you break this down with a little more detail and explanation? I would like to understand this as I think it is very important for us to know what they are trying to do here in 900 MHz. Thank you, John Scrivner rwf wrote: Nextel has been buying up 900 MHz trunked systems for years now. Probably will do what they did to build their first ESMR (Nextel IDEN)- Take perfectly good systems off the air so they can drive the users to an unneeded tcchnology. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom DeReggi Sent: Wednesday, October 25, 2006 9:05 PM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I think this is definately something we need the answer to (What part of 900Mhz). What exactly is "Green Space"? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rick Smith" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Wednesday, October 25, 2006 4:38 PM Subject: [WISPA] Sprint / Nextel to use 900mz for iDen http://www.rcrnews.com/news.cms?newsId=27618 They don't say exact freq's except for the reference to "unlicensed"... R -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
RE: [WISPA] Sprint / Nextel to use 900mz for iDen
Before everyone gets in an uproar about this, has anyone looked in to the actual frequencies being used? I'm pretty sure Nextel has some licensed 900 MHz spectrum. I don't have time to dig around for the information but as I recall they do. I could be wrong. They certainly won't deploy an IDEN system in the unlicensed bandsCome on. They might however cause interference with unlicensed stuff in certain situations where you might be co-located on the same sites. From what I have read I think this is only going to be in selected East Coast cities anyway, and it's a band aid approach to the rebanding process. Thank You, Brian Webster www.wirelessmapping.com <http://www.wirelessmapping.com> -Original Message- From: John Scrivner [mailto:[EMAIL PROTECTED] Sent: Thursday, October 26, 2006 10:30 AM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I am not familiar with the terms you describe below and I am a bit confused. Can you break this down with a little more detail and explanation? I would like to understand this as I think it is very important for us to know what they are trying to do here in 900 MHz. Thank you, John Scrivner rwf wrote: >Nextel has been buying up 900 MHz trunked systems for years now. >Probably will do what they did to build their first ESMR (Nextel IDEN)- >Take perfectly good systems off the air so they can drive the users to an >unneeded tcchnology. > > >-Original Message- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On >Behalf Of Tom DeReggi >Sent: Wednesday, October 25, 2006 9:05 PM >To: WISPA General List >Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen > >I think this is definately something we need the answer to (What part of >900Mhz). What exactly is "Green Space"? > >Tom DeReggi >RapidDSL & Wireless, Inc >IntAirNet- Fixed Wireless Broadband > > >- Original Message - >From: "Rick Smith" <[EMAIL PROTECTED]> >To: "'WISPA General List'" >Sent: Wednesday, October 25, 2006 4:38 PM >Subject: [WISPA] Sprint / Nextel to use 900mz for iDen > > > > >>http://www.rcrnews.com/news.cms?newsId=27618 >> >>They don't say exact freq's except for the reference to "unlicensed"... >>R >> >> >> >>-- >>WISPA Wireless List: wireless@wispa.org >> >>Subscribe/Unsubscribe: >>http://lists.wispa.org/mailman/listinfo/wireless >> >>Archives: http://lists.wispa.org/pipermail/wireless/ >> >> > > > -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
I don't know what the beef is. FleetCall bought up in the vicinity of 100 trunking & SMR channels in each major metro almost 20 yrs ago. They claimed to the FCC that they could serve significantly more users than the typical 100 users/channel of the current early 90s analog technology. 100 channels at 100 users apiece serves only in the vicinity of 10,000 users. With the iDen technology they ultimately served almost half a million in the same geographic area with the same spectrum. So much for the "unneeded technology" assessment. Now that they're called NexTel, sure they continue adding whatever remaining licenses they can get their hands on, but the 800 and 900 Trunking and bands are land-locked (no room for expansion), so there's no new technology targeted to this band that I know of. Now that they're merged with Sprint, it's no secret where their new technology is targeted (WiMAX). Rich - Original Message - From: "John Scrivner" <[EMAIL PROTECTED]> To: "WISPA General List" Sent: Thursday, October 26, 2006 9:29 AM Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I am not familiar with the terms you describe below and I am a bit confused. Can you break this down with a little more detail and explanation? I would like to understand this as I think it is very important for us to know what they are trying to do here in 900 MHz. Thank you, John Scrivner rwf wrote: Nextel has been buying up 900 MHz trunked systems for years now. Probably will do what they did to build their first ESMR (Nextel IDEN)- Take perfectly good systems off the air so they can drive the users to an unneeded tcchnology. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom DeReggi Sent: Wednesday, October 25, 2006 9:05 PM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I think this is definately something we need the answer to (What part of 900Mhz). What exactly is "Green Space"? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rick Smith" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Wednesday, October 25, 2006 4:38 PM Subject: [WISPA] Sprint / Nextel to use 900mz for iDen http://www.rcrnews.com/news.cms?newsId=27618 They don't say exact freq's except for the reference to "unlicensed"... R -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
I am not familiar with the terms you describe below and I am a bit confused. Can you break this down with a little more detail and explanation? I would like to understand this as I think it is very important for us to know what they are trying to do here in 900 MHz. Thank you, John Scrivner rwf wrote: Nextel has been buying up 900 MHz trunked systems for years now. Probably will do what they did to build their first ESMR (Nextel IDEN)- Take perfectly good systems off the air so they can drive the users to an unneeded tcchnology. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom DeReggi Sent: Wednesday, October 25, 2006 9:05 PM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I think this is definately something we need the answer to (What part of 900Mhz). What exactly is "Green Space"? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rick Smith" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Wednesday, October 25, 2006 4:38 PM Subject: [WISPA] Sprint / Nextel to use 900mz for iDen http://www.rcrnews.com/news.cms?newsId=27618 They don't say exact freq's except for the reference to "unlicensed"... R -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
Could they really get by on the low power in the unlicensed noisy bands? Langeler, you know? Everything I have heard is the "big boys" use high power (at least compared to us) and HIGH receive sensitivity because on no noise and that is why is works so well. Except my Nextel has SUCKED for the last two month. Dropped call after dropped call. Brian rwf wrote: Nextel has been buying up 900 MHz trunked systems for years now. Probably will do what they did to build their first ESMR (Nextel IDEN)- Take perfectly good systems off the air so they can drive the users to an unneeded tcchnology. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom DeReggi Sent: Wednesday, October 25, 2006 9:05 PM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I think this is definately something we need the answer to (What part of 900Mhz). What exactly is "Green Space"? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rick Smith" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Wednesday, October 25, 2006 4:38 PM Subject: [WISPA] Sprint / Nextel to use 900mz for iDen http://www.rcrnews.com/news.cms?newsId=27618 They don't say exact freq's except for the reference to "unlicensed"... R -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
RE: [WISPA] Sprint / Nextel to use 900mz for iDen
Nextel has been buying up 900 MHz trunked systems for years now. Probably will do what they did to build their first ESMR (Nextel IDEN)- Take perfectly good systems off the air so they can drive the users to an unneeded tcchnology. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom DeReggi Sent: Wednesday, October 25, 2006 9:05 PM To: WISPA General List Subject: Re: [WISPA] Sprint / Nextel to use 900mz for iDen I think this is definately something we need the answer to (What part of 900Mhz). What exactly is "Green Space"? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rick Smith" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Wednesday, October 25, 2006 4:38 PM Subject: [WISPA] Sprint / Nextel to use 900mz for iDen > http://www.rcrnews.com/news.cms?newsId=27618 > > They don't say exact freq's except for the reference to "unlicensed"... > R > > > > -- > WISPA Wireless List: wireless@wispa.org > > Subscribe/Unsubscribe: > http://lists.wispa.org/mailman/listinfo/wireless > > Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] Sprint / Nextel to use 900mz for iDen
I think this is definately something we need the answer to (What part of 900Mhz). What exactly is "Green Space"? Tom DeReggi RapidDSL & Wireless, Inc IntAirNet- Fixed Wireless Broadband - Original Message - From: "Rick Smith" <[EMAIL PROTECTED]> To: "'WISPA General List'" Sent: Wednesday, October 25, 2006 4:38 PM Subject: [WISPA] Sprint / Nextel to use 900mz for iDen http://www.rcrnews.com/news.cms?newsId=27618 They don't say exact freq's except for the reference to "unlicensed"... R -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/