[WISPA] interference from ships
We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ| Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Mainehttp://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] MicroTik HWMPplus mesh?
Thanks. Just a few more questions please. 1. If you use self-configuring gear doesn't that mean at least as far as the backhaul it's all on the same frequency? Wouldn't a system where you manually configure the backhaul legs to use separate frequencies reduce self-interference and allow avoidance of existing noise sources? 2. To have the system be self-healing as far as not having any customers lose connectivity due to a site failure mean that each customer would need to be able to hear more than one site. So the site density would have to be very high, which again would lead to self-interference, especially if the answer to question #1 above is that the mesh (backhaul) part of the network is all on the same frequency? 3. Don't these mesh networks fall into two categories - 1 free hobbyist best-effort networks using low end gear and modest performance and 2 commercial/industrial/public service/military networks using more powerful and expensive gear (with lower site density and probably even GPS sync) yielding much higher performance. Thanks! Greg On Jun 18, 2010, at 10:00 PM, L. Aaron Kaplan wrote: On Jun 18, 2010, at 7:21 PM, Greg Ihnen wrote: Are you seeing benefits from the mesh approach that you wouldn't get from backhaul/APs? Doesn't the mesh gear usually have omni-directional antennas which can be problematic in an RF polluted environment. Yes, note two things please: 1) you can of course also have a mesh approach with point2multipoint (and even in infrastructure mode!) 2) meshing on layer 3 at least gives you very fast reconfiguration when links break. So in most community networks in Europe that I know (including funkfeuer.at) we use it actually as a fast redundant path selection protocol. (of course, we also actively develop and work on the olsr.org so we might one day end up with a multipath routing meshing daemon. this would be my dream) a. Greg On Jun 18, 2010, at 6:41 PM, L. Aaron Kaplan wrote: I agree with Faisal here... Our experience from the freifunk style networks in Europe is that a mix of backbone/mesh nodes and layer 3 meshing gets the job done. Why layer 3? Because you don't want it all to be a single layer 2 broadcast area :) Your spectrum is just too valuable to send every broadcast message to all others in the network. Combine that with BGP/OSPF/whatever backbone links which are built point to point (or point to a few multipoints) with high capacity and you are set. This way you can even have layer 2 meshes interoperating with different meshes or OSPF/BGP/IS-IS/whatever protocol backbone networks. WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] What, no response to the FCC vote today?
At 6/19/2010 12:36 AM, MDK wrote: This may be our last chance to survive in this business. I know what my position is, and it should be clear to most of you. However, the FCC needs to hear from the smaller operators, and from small business saying Hands off! We can't afford your wishes. And they need to hear it from the providers and the customers of those providers. I may be preparing a formal Response to the Inquiry. I participate in a lot of FCC proceedings, sometimes in my own name (d/b/a Ionary Consulting), sometimes on behalf of an ad-hoc group of clients (typically small CLECs) who cosign and have say on the response. At this stage (NOI) it's fairly wide open. The real devil is in the details, which come later (the NPRM). I suggest actually reading Tatel's ruling overturning the Comcast Order. You can see how the FCC is basically ignoring the spirit of his Order while meeting one aspect of the letter. (I'm probably out today so don't expect responses before much later.) -- Fred Goldsteink1io fgoldstein at ionary.com ionary Consulting http://www.ionary.com/ +1 617 795 2701 WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] interference from ships
Plug the damn hole! - lol! Sorry, I couldnt help it :) Since it's a UK ship, I wonder if this has anything to do with it? http://www.eubusiness.com/topics/telecoms/mobile-ships.01/ On Sat, Jun 19, 2010 at 8:14 AM, jp j...@saucer.midcoast.com wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ | Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Maine http://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] interference from ships
Possible but don't quit believe so since 900MHz GSM uses 890-914Mhz for uplink (cell to base station), and 921-960Mhz for download (basestation to cell). That strong signal wouldn't come from cells and the basestation would just ruin the top part of the frequency. Maritime cell systems I seen don't offer 3G type services and GSM gprs/edge channel size is 200khz. 4G will have 4 to 20MHz dynamic channel size. Would really need to verify that the signal for sure is coming from the ship and not somewhere else. If that is the case maybe look at getting hold of someone from the ship to check with them what it might be. Dont forget to shut down your own AP while you run the SA at the AP location to avoid false readings and make sure it's not actually something newly installed at that location. / Eje -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of RickG Sent: Saturday, June 19, 2010 1:23 PM To: WISPA General List Subject: Re: [WISPA] interference from ships Plug the damn hole! - lol! Sorry, I couldnt help it :) Since it's a UK ship, I wonder if this has anything to do with it? http://www.eubusiness.com/topics/telecoms/mobile-ships.01/ On Sat, Jun 19, 2010 at 8:14 AM, jp j...@saucer.midcoast.com wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ | Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Maine http://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] MicroTik HWMPplus mesh?
On Fri, Jun 18, 2010 at 9:43 PM, Faisal Imtiaz fai...@snappydsl.net wrote: that's a few radio hops away from anywhere. And that's one reason why per-hop latency is all-critical To put things in context... from what we have seen typical latency between radios (for a single link) are between 1ms to 2ms... The Moto Canopy are an exception they have much higher latencybecause of what they do and how they do it so even if you are going thru 20 radios.. you are talking about 15-20 ms per-hop performance may be thougher than per-hop latency... it usually divides by 2, so n hops would be 1/2^n performance of the main node. Which could be fine if you can provide fairness to prevent a kind of capture effect of the nearest nodes. Rubens WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] interference from ships
CAN THAT BE SOME FORM OF RADAR? -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of Eje Gustafsson Sent: Saturday, June 19, 2010 12:01 PM To: 'WISPA General List' Subject: Re: [WISPA] interference from ships Possible but don't quit believe so since 900MHz GSM uses 890-914Mhz for uplink (cell to base station), and 921-960Mhz for download (basestation to cell). That strong signal wouldn't come from cells and the basestation would just ruin the top part of the frequency. Maritime cell systems I seen don't offer 3G type services and GSM gprs/edge channel size is 200khz. 4G will have 4 to 20MHz dynamic channel size. Would really need to verify that the signal for sure is coming from the ship and not somewhere else. If that is the case maybe look at getting hold of someone from the ship to check with them what it might be. Dont forget to shut down your own AP while you run the SA at the AP location to avoid false readings and make sure it's not actually something newly installed at that location. / Eje -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of RickG Sent: Saturday, June 19, 2010 1:23 PM To: WISPA General List Subject: Re: [WISPA] interference from ships Plug the damn hole! - lol! Sorry, I couldnt help it :) Since it's a UK ship, I wonder if this has anything to do with it? http://www.eubusiness.com/topics/telecoms/mobile-ships.01/ On Sat, Jun 19, 2010 at 8:14 AM, jp j...@saucer.midcoast.com wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ | Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Maine http://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] interference from ships
I'd contact the ship's owner. Greg On Jun 19, 2010, at 6:56 PM, Chuck Profito wrote: CAN THAT BE SOME FORM OF RADAR? -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of Eje Gustafsson Sent: Saturday, June 19, 2010 12:01 PM To: 'WISPA General List' Subject: Re: [WISPA] interference from ships Possible but don't quit believe so since 900MHz GSM uses 890-914Mhz for uplink (cell to base station), and 921-960Mhz for download (basestation to cell). That strong signal wouldn't come from cells and the basestation would just ruin the top part of the frequency. Maritime cell systems I seen don't offer 3G type services and GSM gprs/edge channel size is 200khz. 4G will have 4 to 20MHz dynamic channel size. Would really need to verify that the signal for sure is coming from the ship and not somewhere else. If that is the case maybe look at getting hold of someone from the ship to check with them what it might be. Don’t forget to shut down your own AP while you run the SA at the AP location to avoid false readings and make sure it's not actually something newly installed at that location. / Eje -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of RickG Sent: Saturday, June 19, 2010 1:23 PM To: WISPA General List Subject: Re: [WISPA] interference from ships Plug the damn hole! - lol! Sorry, I couldnt help it :) Since it's a UK ship, I wonder if this has anything to do with it? http://www.eubusiness.com/topics/telecoms/mobile-ships.01/ On Sat, Jun 19, 2010 at 8:14 AM, jp j...@saucer.midcoast.com wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ| Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Mainehttp://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] interference from ships
there it is sub surface low freq radar Google and http://en.wikipedia.org/wiki/Low-frequency_radar are our friends... -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of Eje Gustafsson Sent: Saturday, June 19, 2010 12:01 PM To: 'WISPA General List' Subject: Re: [WISPA] interference from ships Possible but don't quit believe so since 900MHz GSM uses 890-914Mhz for uplink (cell to base station), and 921-960Mhz for download (basestation to cell). That strong signal wouldn't come from cells and the basestation would just ruin the top part of the frequency. Maritime cell systems I seen don't offer 3G type services and GSM gprs/edge channel size is 200khz. 4G will have 4 to 20MHz dynamic channel size. Would really need to verify that the signal for sure is coming from the ship and not somewhere else. If that is the case maybe look at getting hold of someone from the ship to check with them what it might be. Dont forget to shut down your own AP while you run the SA at the AP location to avoid false readings and make sure it's not actually something newly installed at that location. / Eje -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of RickG Sent: Saturday, June 19, 2010 1:23 PM To: WISPA General List Subject: Re: [WISPA] interference from ships Plug the damn hole! - lol! Sorry, I couldnt help it :) Since it's a UK ship, I wonder if this has anything to do with it? http://www.eubusiness.com/topics/telecoms/mobile-ships.01/ On Sat, Jun 19, 2010 at 8:14 AM, jp j...@saucer.midcoast.com wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ | Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Maine http://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] interference from ships
That's funny. That article claims that Below 900 MHz the target radar cross section increases exponentially, however the increased radar cross section means that there is much more radar return from undesirable sources, such as cloud cover and rain (cf. weather radar). but when I worked on ships we used S and X band radars. The S band (lower frequency) was better in the rain and usually had better range, but the X band gave more detailed and sharper images (such as a more accurate and realistic representation of the coastline, and a more accurate representation of the size of boats and ships) but it had more problems with rain clutter. I guess that's why Wikipedia is free. You get what you pay for. Greg On Jun 19, 2010, at 6:59 PM, Chuck Profito wrote: there it is sub surface low freq radar Google and http://en.wikipedia.org/wiki/Low-frequency_radar are our friends... -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of Eje Gustafsson Sent: Saturday, June 19, 2010 12:01 PM To: 'WISPA General List' Subject: Re: [WISPA] interference from ships Possible but don't quit believe so since 900MHz GSM uses 890-914Mhz for uplink (cell to base station), and 921-960Mhz for download (basestation to cell). That strong signal wouldn't come from cells and the basestation would just ruin the top part of the frequency. Maritime cell systems I seen don't offer 3G type services and GSM gprs/edge channel size is 200khz. 4G will have 4 to 20MHz dynamic channel size. Would really need to verify that the signal for sure is coming from the ship and not somewhere else. If that is the case maybe look at getting hold of someone from the ship to check with them what it might be. Don’t forget to shut down your own AP while you run the SA at the AP location to avoid false readings and make sure it's not actually something newly installed at that location. / Eje -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of RickG Sent: Saturday, June 19, 2010 1:23 PM To: WISPA General List Subject: Re: [WISPA] interference from ships Plug the damn hole! - lol! Sorry, I couldnt help it :) Since it's a UK ship, I wonder if this has anything to do with it? http://www.eubusiness.com/topics/telecoms/mobile-ships.01/ On Sat, Jun 19, 2010 at 8:14 AM, jp j...@saucer.midcoast.com wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ| Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Mainehttp://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/
Re: [WISPA] interference from ships
yes Greg, we used to think a Smart Bridge was the Cat's Meow then the CB3 came out! :-) Since that's an exploration drilling ship, I'll bet it's some sort of sub surface positioning radar/ sonar/ or some such, linked to the thrusters and gps to keep it on position. I wonder if it could be worse in the water? But a mile away, sideways, that would be a lot of water to penetrate with a side lobe, or even reflect. Could they call the harbor master and ask him to contact the Capt or 1st officer. -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of Greg Ihnen Sent: Saturday, June 19, 2010 4:36 PM To: WISPA General List Subject: Re: [WISPA] interference from ships That's funny. That article claims that Below 900 MHz the target radar cross section increases exponentially, however the increased radar cross section means that there is much more radar return from undesirable sources, such as cloud cover and rain (cf. weather radar). but when I worked on ships we used S and X band radars. The S band (lower frequency) was better in the rain and usually had better range, but the X band gave more detailed and sharper images (such as a more accurate and realistic representation of the coastline, and a more accurate representation of the size of boats and ships) but it had more problems with rain clutter. I guess that's why Wikipedia is free. You get what you pay for. Greg On Jun 19, 2010, at 6:59 PM, Chuck Profito wrote: there it is sub surface low freq radar Google and http://en.wikipedia.org/wiki/Low-frequency_radar are our friends... -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of Eje Gustafsson Sent: Saturday, June 19, 2010 12:01 PM To: 'WISPA General List' Subject: Re: [WISPA] interference from ships Possible but don't quit believe so since 900MHz GSM uses 890-914Mhz for uplink (cell to base station), and 921-960Mhz for download (basestation to cell). That strong signal wouldn't come from cells and the basestation would just ruin the top part of the frequency. Maritime cell systems I seen don't offer 3G type services and GSM gprs/edge channel size is 200khz. 4G will have 4 to 20MHz dynamic channel size. Would really need to verify that the signal for sure is coming from the ship and not somewhere else. If that is the case maybe look at getting hold of someone from the ship to check with them what it might be. Don't forget to shut down your own AP while you run the SA at the AP location to avoid false readings and make sure it's not actually something newly installed at that location. / Eje -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of RickG Sent: Saturday, June 19, 2010 1:23 PM To: WISPA General List Subject: Re: [WISPA] interference from ships Plug the damn hole! - lol! Sorry, I couldnt help it :) Since it's a UK ship, I wonder if this has anything to do with it? http://www.eubusiness.com/topics/telecoms/mobile-ships.01/ On Sat, Jun 19, 2010 at 8:14 AM, jp j...@saucer.midcoast.com wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ| Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Mainehttp://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe:
Re: [WISPA] interference from ships
Another option is they're running something that's not street legal (something you couldn't get away with running ashore but out at sea you don't have to worry a about an FCC van bristling with antennas direction finding it's way to your location) that normally they just run at sea and someone forgot to turn off. Greg On Jun 19, 2010, at 7:23 PM, Chuck Profito wrote: yes Greg, we used to think a Smart Bridge was the Cat's Meow then the CB3 came out! :-) Since that's an exploration drilling ship, I'll bet it's some sort of sub surface positioning radar/ sonar/ or some such, linked to the thrusters and gps to keep it on position. I wonder if it could be worse in the water? But a mile away, sideways, that would be a lot of water to penetrate with a side lobe, or even reflect. Could they call the harbor master and ask him to contact the Capt or 1st officer. -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of Greg Ihnen Sent: Saturday, June 19, 2010 4:36 PM To: WISPA General List Subject: Re: [WISPA] interference from ships That's funny. That article claims that Below 900 MHz the target radar cross section increases exponentially, however the increased radar cross section means that there is much more radar return from undesirable sources, such as cloud cover and rain (cf. weather radar). but when I worked on ships we used S and X band radars. The S band (lower frequency) was better in the rain and usually had better range, but the X band gave more detailed and sharper images (such as a more accurate and realistic representation of the coastline, and a more accurate representation of the size of boats and ships) but it had more problems with rain clutter. I guess that's why Wikipedia is free. You get what you pay for. Greg On Jun 19, 2010, at 6:59 PM, Chuck Profito wrote: there it is sub surface low freq radar Google and http://en.wikipedia.org/wiki/Low-frequency_radar are our friends... -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of Eje Gustafsson Sent: Saturday, June 19, 2010 12:01 PM To: 'WISPA General List' Subject: Re: [WISPA] interference from ships Possible but don't quit believe so since 900MHz GSM uses 890-914Mhz for uplink (cell to base station), and 921-960Mhz for download (basestation to cell). That strong signal wouldn't come from cells and the basestation would just ruin the top part of the frequency. Maritime cell systems I seen don't offer 3G type services and GSM gprs/edge channel size is 200khz. 4G will have 4 to 20MHz dynamic channel size. Would really need to verify that the signal for sure is coming from the ship and not somewhere else. If that is the case maybe look at getting hold of someone from the ship to check with them what it might be. Don't forget to shut down your own AP while you run the SA at the AP location to avoid false readings and make sure it's not actually something newly installed at that location. / Eje -Original Message- From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On Behalf Of RickG Sent: Saturday, June 19, 2010 1:23 PM To: WISPA General List Subject: Re: [WISPA] interference from ships Plug the damn hole! - lol! Sorry, I couldnt help it :) Since it's a UK ship, I wonder if this has anything to do with it? http://www.eubusiness.com/topics/telecoms/mobile-ships.01/ On Sat, Jun 19, 2010 at 8:14 AM, jp j...@saucer.midcoast.com wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ| Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Mainehttp://www.midcoast.com/ */ WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org
Re: [WISPA] MicroTik HWMPplus mesh?
At 6/19/2010 06:43 PM, Rubens Kuhl wrote: On Fri, Jun 18, 2010 at 9:43 PM, Faisal Imtiaz fai...@snappydsl.net wrote: that's a few radio hops away from anywhere. And that's one reason why per-hop latency is all-critical To put things in context... from what we have seen typical latency between radios (for a single link) are between 1ms to 2ms... The Moto Canopy are an exception they have much higher latencybecause of what they do and how they do it so even if you are going thru 20 radios.. you are talking about 15-20 ms per-hop performance may be thougher than per-hop latency... it usually divides by 2, so n hops would be 1/2^n performance of the main node. Which could be fine if you can provide fairness to prevent a kind of capture effect of the nearest nodes. This is one of the problems with any kind of best efforts routing or bridging. Loss does accumulate. Of course it's the single-frequency meshes where loss goes totally gaga. One of the advantages of Carrier Ethernet with Q-in-Q is that CIRs can be assigned to different points along the way, with reserved capacity, so the near-in nodes don't hog everything. I don't think HWMPplus does full CE, but it may have some tools to play with. If anybody can suggest a better software load for a field-mountable multi-radio processor, notably one that does MEF CE, I'm not wedded to MicroTik. This is interim, after all; we hope to have our own code at some point. On the Layer 2 v 3 thing, the distinction is artificial. Off the shelf, LAN-oriented L2 switching does dumb bridging, based on an assumption that it's all on-site with plenty of zero-cost orange hose bandwidth to play with. So STP just avoids loops. IP itself is really a layer 2 protocol too! This is non-obvious, but an IP address names the interface, not the application or host, and thus it is also a layer 2 address. TCP/IP doesn't even have a network layer, just this stub that assigns two-to-three-level second names (IP addresses to interfaces whose MAC address is totally flat. If you assign node IDs in Layer 2, it becomes smarter than IP, and IP can thus be run as a dumb stub protocol. (Suggested reading: Patterns in Network Architecture: A Return to Fundamentals, by John Day.) -- Fred Goldsteink1io fgoldstein at ionary.com ionary Consulting http://www.ionary.com/ +1 617 795 2701 WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] interference from ships
At 6/19/2010 08:14 AM, you wrote: We've got a 700' drilling ship moored about a mile off our coast for a few days for repairs. http://www.stena-drilling.com/sub.asp?m=drillingp=stenaforth Since it came in, 900mhz within a couple miles of it has stopped working. We went out with the spectrum analyser after the Alvarion software spectrum analyzer went off the charts. The HP spectrum analyzer with a 9dbi yagi was picking up big fat gaussian shaped signals at -20 to -25dbm about 10-15mhz wide in the middle. I sent my guys to a second location with the spectrum analyzer just to make sure they weren't seeing local interfernce and they saw the same thing. A legal amount of power output would cause it to come in at about -50. Anyone else seen such strange stuff coming from this type of ship? I've never seen any trouble from any ship ever, though this is the first drilling ship to visit our area. Hi Jason, The ship may be doing something perfectly legal, just incompatible with us. The 902-928 band's primary allocation, in the FCC table of allocations, is radiolocation (radar). So it could be blasting high power out on 915 (+/- 13) as part of a radar system, which it probably doesn't need to be running in port but doesn't turn off. Also, the band is assigned to ISM (Part 18) heating applications. That has a cap on power leakage, sort of, but no explicit cap on power, and it appears that the leakage is expressed in relation to the actual power used. There could be some kind of process taking place there that uses ISM, though radar looks more likely to me. The FCC lets us use these bands without license because they're basically junkyards. -- Fred Goldsteink1io fgoldstein at ionary.com ionary Consulting http://www.ionary.com/ +1 617 795 2701 WISPA Wants You! Join today! http://signup.wispa.org/ WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
Re: [WISPA] MicroTik HWMPplus mesh?
You know your stuff in-side out, hands down there is no argument about that :) Getting back to your original quest... You are going to find the following:- The non-licensed wireless world is not as mature as the wire line world... think of today's wire less world being what the wire line world used to be about 10 -15 years back. Most of what you are citing from the Ethernet World, only became available and in common use in the last 10 years or so... before that, everyone was happy doing conversions from TDM ...(speaking loosely). In the wireless world of today, especially what folks here deal with, have some set outer boundaries ... a few of these are things like... performance, based on standard(s) , LOW COST, small in power consumption, etc etc... If you have a particular setup from the Wireline world in mind, you can always accomplish that by using wireline routers switches and just use the wireless radios as bridges...Mikrotik is one on the very few mfg. which offers a whole line up of products, which can be mixed and matched to do routing / switching / with wired or wireless connections.. and a consistent OS... Having said that, hopefully you will realize that all of the so called Wireless Radios available in the marketplace are nothing more than a SBC, with a Wireless Radio (chip), a specialized Antenna (if integrated) and a customer OS.. most of the time is either based on Linux / BSD or the same base OS that is used for developing the Wireline routers / switches. Most of the secret sauce that we all get excited about tends to be in the 'software Driver' of the raw radio card or the Antenna...the rest of the routing / switching / mgmt stuff, folks either accept what came with that particular radio or use their own preferred router /switch to accomplish. A great example of that is what Ubiquiti is doing with their M Series... their 'Radio' are running linux (based on openwrt) their special sauce is their proprietary driver talking to the actual radio card, and their Antennas.. First set of products are based on 802.11n standard... covering 2.4Ghz 5.XGhz... but there are planning to come up with radios running in 3.65 and (I am guessing here..) 900Mhz...running the same 'protocols' as 802.11n.. Actually seeing what 802.11n with Mimio antennas can do when compared to the traditional 802.11a/b/g... it is rather amazing. You can use their radios to do other stuff by modding the linux os they are running or simply using them just as a bridge, to connect your favorite routing / switching platform. BTW, Aaron Kaplan was trying to say, in not too many words.. that most of the mesh networks which have utilized the traditional Wireline protocols, (weather they are single frequency or not) have the usual problem .(most wireline protocols are not concerned with link quality...), and this is the reason why they developed the OSLR ... which takes link quality into account as well when making routing decision.. but you are not going to find OSLR in commercial radios not at the moment... If you look at all of the folks who are delivering successful mesh products, you will find them to be using 'proprietary' developed mechanisms to deal with the issues..e.g. Ruckus Wireless uses it's special antennas and a 'zone controller' to keep the Mesh radios in tip top shape, by dynamically adjusting all of the parameters on a real time basis.. As far as finding a multi-radio board... there are a few available best to see the link to Wili Box site that I had sent in an earlier email... they list out a number of mfg. for both the sbc's and the radios.. the question you will have to figure out is..on what part of the 'network design' ... 'ip routing ?' you will be willing to make a compromise on...and you still have not addressed the question of Antennas:) after using a good working 802.11n radios with MiMo Antennas... it is rather hard to go back to regular stuff... Faisal Imtiaz Snappy Internet Telecom On 6/19/2010 8:50 PM, Fred Goldstein wrote: This is one of the problems with any kind of best efforts routing or bridging. Loss does accumulate. Of course it's the single-frequency meshes where loss goes totally gaga. One of the advantages of Carrier Ethernet with Q-in-Q is that CIRs can be assigned to different points along the way, with reserved capacity, so the near-in nodes don't hog everything. I don't think HWMPplus does full CE, but it may have some tools to play with. If anybody can suggest a better software load for a field-mountable multi-radio processor, notably one that does MEF CE, I'm not wedded to MicroTik. This is interim, after all; we hope to have our own code at some point. On the Layer 2 v 3 thing, the distinction is artificial. Off the shelf, LAN-oriented L2 switching does dumb bridging, based on an assumption that it's all on-site with plenty of zero-cost orange hose bandwidth to play with.
