Testing mail server. Mike Bushard, Jr Wisper Wireless Solutions, LLC -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Marlon K. Schafer (509) 982-2181 Sent: Monday, June 26, 2006 10:41 AM To: WISPA General List Subject: [WISPA] Fw: [isp-wireless] Sector Antenna's I want the Best!
I thought some here my get some use out of this thread. Hope it helps, Marlon (509) 982-2181 Equipment sales (408) 907-6910 (Vonage) Consulting services 42846865 (icq) And I run my own wisp! 64.146.146.12 (net meeting) www.odessaoffice.com/wireless www.odessaoffice.com/marlon/cam ----- Original Message ----- From: "Marlon K. Schafer" <[EMAIL PROTECTED]> To: <isp-wireless@isp-wireless.com> Sent: Sunday, June 25, 2006 7:10 AM Subject: Re: [isp-wireless] Sector Antenna's I want the Best! > David, as usual, great thoughts. > > Let me add a bit here on the "but what should *I* do???" side of things. > > I have both omni and sector solutions on the air. I have both non amped > and amped of both. Let me show you how/where I get to each option..... > > Very rural, few customers likely in the first 18 to 24 months. The > AVERAGE ap out there will service from 75 to 100 subs jut fine as long as > you don't have many hogs. So in a case where I'll likely have less than > 50 users I'll go with an amplified omni unless the geography is such that > there's just no way to get more than a few miles of service out to people. > > Down town where there are a few companies in the shadows of my main wpops > I may put in an omni. Low gain so that coverage only extends a few blocks > etc. > > I have some sites on hill sides that overlook many hundreds of houses. > Very stiff competition so there number of customers isn't really an issue. > Spectrum issues are though. There are at least 4 other wisps on the hill, > one of whom is both stupid and mean. You know the type, never met an amp > he didn't like..... He's got a sector that points to NO customers, only > to my tower. The good news is that operators like that eventually run out > of money and will go away. But in this location I've got SIX different > systems. 4 of them are 2.4 and three of those are on the same channel. > Remember you have not only the noise that your ap's see to deal with but > also the noise that your cpe sees coming from his ap's. In my case I have > sectors as narrow as 30* (panel antennas make nice sectors and are > cheap!). I also rotate polarity ass needed to help bleed off as much noise > as I can. > > There are other spots that I have no customers behind a tower on a hill so > sectors just make sense anyway. If long range is needed OR if I do have a > customer or two out of the main lobe of the sector I may put an amp on the > sector too. Usually there's no need though. It's surprising that a > sector with an amp and running at the max legal 4 watts will often not > give much more coverage than a sector with no amp running at 1 or 2 watts. > The main reason for that is the noise that the amp injects into the system > keeps your SNR about the same as often as not. > > There's also a cost factor. A good Maxrad adjustable beam sector (the > only ones I buy nowadays) is about $400 from EC. The H-Pol version is > $250ish. I tried the cheap sectors from Maxrad and another company and all > systems running them act just a bit strange. Drop in a good antenna and > it's AMAZING how much better the system runs! A good omni antenna from > Maxrad is about $100. Others that are worth having are in that ball park > (remember, there's ALMOST NEVER a good reason to run an omni over > 10dB!!!!!!!!!! The high gain ones are just more money for the sales > geeks). > > Sooo, 360* coverage with an omni and amp. $400 for a good ap, $250 for a > good amp ($800? for a great one), $100 for an antenna, $25 to $150 for > cables and we're at around $1000 for an omni based wpop. (plus backhaul > but we'd need that anyhow) For a sectored solution you've got $400 for an > ap, $400 for an antenna, $5 to $25 for cable (cat 5 this time). Times > THREE or more puts us into the $1200 to $1500 range. > > Now, there are some that say you should put in the sectors just because > it's so close in price and you have better spectrum usage that way. I > don't really buy into that theory. You'll usually use ALL spectrum when > sector vs. one channel when using an omni. However, with sectors it's > easier to avoid noise coming from different directions on different > channels/polarities. > > The FIRST thing you should do is figure out if there are enough customers > in a given area to at least pay the bills. Then you need to run a > spectrum sweep to make sure that the band you want to use is indeed usable > (do NOT make the mistake I did and assume that because you are out in BFE > you'll not have other wireless users in the area). NOTE: Netstubler or > anything like it will NOT be of much use for this. You need a spectrum > analyzer. Rent one for a week or two. It's well worth the cost as it'll > often save you huge amounts of time and money down the road. Been there, > done that, ain't doin' it again!!!! > > Lastly, find a person or two who's advice you trust and don't deviate too > much from what you read on these lists. Hang on to him and let him help > design your system. He'll then also be able to help you fix the things > that no one will know about till you've built it. There's always > something that doesn't show up till that 20th customer is online..... > > Hope that helps, > marlon > > ----- Original Message ----- > From: "David Vrablic" <[EMAIL PROTECTED]> > To: <isp-wireless@isp-wireless.com> > Sent: Sunday, June 25, 2006 5:56 AM > Subject: Re: [isp-wireless] Sector Antenna's I want the Best! > > >> Good morning Brad, >> Thanks for a perfect explanation of where I was going with my opinions. >> A sparsely populated rural market is a "whole nuther ball game" compared >> to a heavily populated urban market where Time Warner has lit up every >> household with a Linksys AP on Ch 6. (HEY! Time Warner, You're a >> Jerk!) >> ----- >> Now lets get back to answering the young mans question: >> The truth is I have enough population that anywhere I would install a >> sector, Sales can get customers. >> That fact changes the whole design picture. >> ---------------------- >> This especially holds true if you are designing a meshed ring / star >> network. >> You have to design it and plan for it, even if you don't build it. >> You have to design your BH route / topology to cover the whole area you >> might wish to cover before you fill it in with sector or node coverage. >> You are right on the money with your consideration of the opposing beam >> width in use. >> If polarity of the beam "in either axis" is too wide, you are subject to >> waste and noise, if too narrow you loose coverage but increase >> reliability for where it does cover. >> I believe careful selection of antennas is where this thread started and >> is right where good sector coverage design starts. >> ----------------- >> The man asked for Best . >> That can be Reliability, Ease of mounting, Predictable design plots, >> Polarity and overall bang for the buck. >> What I gleaned from the post was " What is the best first time out >> coverage approach to start a new WISP business with. >> My answer is: It all depends. (On a lot of things that only he can >> answer) >> I had a real eye opener when I started building my first Muni system and >> started reading up on the "Cylindrical Model" where you can envision >> coverage areas in 3D . >> The white paper treated the sectors like stacking cans of different sizes >> to represent the actual service areas in buildings. >> I realized that this was an omni approach and wasted a lot of coverage >> and had a lot of overlap that made for a lot of self generated spectral >> noise to overcome. >> I thought it over and would rather think of my directional sectors as >> wedges of cheese. >> I can even reuse the same frequency back to back if I am on the opposite >> side of a bell or clock tower. >> I believe you have to engineer everything not just put up an omni, that >> with any success, you will be pulling down and replacing with sectors >> anyway. >> ---------------- >> Changing subject here: Adaptive "Smart Antenna Systems" a look at the >> future? >> Just for fun take a look at the Netgear MIMO AP. >> (Fun to play with and has pretty glimmering lights dancing around in a >> circle. >> Unfortunately it doesn't have very good coverage) >> It has 7 internal antennas that scan in a circle and stop to transmit / >> receive for each transmission. >> Now take that concept "out of the box" with external antennas and a >> brave new world evolves. >> It is something that is long overdue. >> Also I would believe that "Point to point " rules would apply. >> --------------- >> Oh well Back to the Cheese errr Drawing board I have a small village >> coverage to design this week. ;-) >> >>> >>> Simple fact is the BG one channel amp & omni approach will only afford >>> you >>> the capacity of that one radio. In contrast sectors allow you multiple >>> radios giving you many times the scalability capacity and frequency >>> agility. >>> >>> >> David L. Vrablic >> Wireless Network Engineer >> Logical Net Wireless >> Schenectady, NY, 12305 >> --------------------------------- >> Office 518-292-4519 >> Cell 518-376-2940 >> -- 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/
