Ok Jack, I have to admit, I have not read your book, but if it reads like this discussion, I have no desire too, unless you 1. either state that your book is for the advanced wireless subjects, or 2. Thoroughly describe your acronyms.
FYI, I do understand most of the poster's acronyms, but for the average WISP operator, I doubt they do. I have a BS in Electrical Engineering and a BS in Management of Information Sciences, not to be tooting my own horn. No, I do not work for Alvarion or Motorola, nor do I have a desire too. Maybe I was in the wrong with my post about the poster's acronyms and my direct criticism with the use of acronyms. I also believe your post was in direct comment to me about my understanding and involvement of WISP activities. I publicly admit, I am not a member of WISPA at the moment, and as long as as an acting officer or "supreme WISPA being" is degrading me, I will not become a member. Scottie Arnett President Info-Ed, Inc. Broadband Internet Service Provider ---------- Original Message ---------------------------------- From: Jack Unger <[email protected]> Date: Sat, 03 Oct 2009 22:39:38 -0700 ><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> ><html> ><head> > <meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type"> > <title></title> ></head> ><body bgcolor="#ffffff" text="#000000"> >Yep it's too bad that many wireless ISPs have no interest in learning >about wireless. <br> ><br> >Scottie Arnett wrote: ><blockquote cite="mid:[email protected]" > type="cite"> > <pre wrap="">I am reading your response and can not decipher all your > algorithms? Point that out and I will have a much more understanding of what > you are scientifically trying to say. Most WISPS have absolutely no > scientific background! > >John > >---------- Original Message ---------------------------------- >From: "Lawrence E. Bakst" <a class="moz-txt-link-rfc2396E" >href="mailto:[email protected]";><[email protected]></a> >Reply-To: WISPA General List <a class="moz-txt-link-rfc2396E" >href="mailto:[email protected]";><[email protected]></a> >Date: Sun, 4 Oct 2009 00:15:45 -0400 > > </pre> > <blockquote type="cite"> > <pre wrap="">I think you guys know most of this already, but here is my > take FWIW. > >I'm not a WISP, but I spent 5 years leading the design and development of an >802.11[agb] security system. We did our own polling solution based on 802.11e >HCCA to solve the RTS/hidden node problem. > >All things being equal (which they often aren't) 802.11b will give you a >higher S/N and C/I than 802.11g, because in almost all cases and especially at >higher speeds. 802.11g has to lower the PA power because of the PAPR of OFDM >and meeting the 802.11g EVM spec. > >It is true that 2.4 GHz can be very polluted. We found the noise floor to be >really awful. You would be surprised by the number of "entities" that know >they are way over the FCC max power in 2.4 GHz, but I digress. We once >measured over 300 PHY errors a second on an "unused" 2.4 GHz channel. The >number went down to 150 PHY errors a second inside an FCC chamber, if you can >believe that. > >Having said all that we didn't use 802.11b at all because it's data rates are >too low for video. > >Also while we supported 2.4 GHz, we mostly deployed at 5.8 GHz ISM because of >the increased power available there and the pollution was much less, but that >maybe different now. > >For 802.11[ag] mutlipoint, the sweet spot speed wise is 18-36 Mbps. It's very >hard to keep a multipoint system at 48 or 54 Mbps because you need a great >deal of link margin and with all cards you loose power as the speed increases >to maintain PAPR/EVM. For point to point with direction antenna relief you can >often maintain 48 or 54. > >Antennae make a big difference, as others have noted horizontal polarization >is usually best and make the beam as narrow as you can afford because it >raises the effective gain. However, if you are in an area where everyone else >is horizontal it can make sense to try vertical. With some of the antennae we >used that was as simple as rotating the antenna 90 deg at both ends. > >Watch out for crappy antennae, cheap cable, bad connectors, and so on. That >can often cost you a few dB. In the product I designed I spent more time then >I care to admit trying to make a very tough loss budget that I set out as a >goal. > >There is no substitute for link margin, you can never really have enough. > >I can confirm that our sweeps with a spectrum analyzer show lots of >opportunity to use 5 and 10 MHz channels, as others have also noted. For WISPs >it would be "nice" if chip vendors designed the radios so that you could set >the channel bandwidth from 5-40 MHz in 1 MHz increments. It can be done but >probably won't be, although maybe the Microsoft WhiteFI stuff force the chip >vendors to do it. In WiMax and LTE they are already doing some things close to >this. Still 5, 10, and 20 isn't bad and probably hits the sweet spot or 80/20 >rule. > >One of the down sides of fitting a 5 or 10 MHz channel in a sweet spot is that >it can change at any time. > >Best, > >leb > >At 9:58 AM -0500 10/1/09, Jason Hensley wrote: > </pre> > <blockquote type="cite"> > <pre wrap="">In 2.4 land, if you have a lot of noise, which protocol is > better - B or G? >Is it better to run an AP as locked into one mode or is it OK to do a mix? > >Max I want off of 2.4 customers is 3meg so not that worried about the extra >speed that G will provide, but, I would like to know which is more stable? >I've always thought that B was more stable overall but just provided less >bandwidth. I've gotten some info that may counter that. What's the >real-world experience with folks in a high-noise environment, combined with >a higher useage AP? > >I've got an AP that we've run in B mode only for a while. We've started >having problems with it - speeds go from 3meg at the customer to 200k and >fluctuate constantly. We've worked with RTS, ACK timeouts, etc etc and >nothing seems to have improved the stability. For testing purposes we put >up another AP right next to the one we're having trouble with. Switched two >of our gaming clients to that one (setup as G mode only) and they seem to be >doing better, but not quite as good as we feel they could be. This is on >Deliberant AP's (Duos). The backhaul part of it is not the issue - we can >pull close to 15meg back to our office when cabled into the AP. We have >other Deliberant APs that are running MANY more clients than this one so we >know it's not limitations of the equipment. AP is on top of a water tower. >Have taken all clients off and brought them back on one by one and it did >not reveal anything significant. With just one customer on the AP started >acting up again. Swapped radios in the AP thinking we could have one going >bad and still no luck. > >2.4 antennas are H-pol. We have a ton of noise in the area, but we've been >through basically every channel and it did not help either. Other AP's in >the vicinity are performing fine. Thought of the multipath issue so we >raised our test AP up a little higher than the other one. As I said, the >test AP seems to be better, but next to it on top of the tower we can get >around 8 or 9 meg down (locked into G mode), but at the CPE's we're still >barely getting 2.5-2.8meg. > >Any thoughts? We changed everything we can. The new "test" AP has a 9db >antenna compared to the 13db on the "production" AP. Other than that, they >are identical as far as equipment goes. > >So, back to the subject question though, what's real-world experience with >G-only mode in the field? > > > > >-------------------------------------------------------------------------------- >WISPA Wants You! Join today! ><a class="moz-txt-link-freetext" >href="http://signup.wispa.org/";>http://signup.wispa.org/</a> >-------------------------------------------------------------------------------- > >WISPA Wireless List: <a class="moz-txt-link-abbreviated" >href="mailto:[email protected]";>[email protected]</a> > >Subscribe/Unsubscribe: ><a class="moz-txt-link-freetext" >href="http://lists.wispa.org/mailman/listinfo/wireless";>http://lists.wispa.org/mailman/listinfo/wireless</a> > >Archives: <a class="moz-txt-link-freetext" >href="http://lists.wispa.org/pipermail/wireless/";>http://lists.wispa.org/pipermail/wireless/</a> > </pre> > </blockquote> > <pre wrap=""> >-- ><a class="moz-txt-link-abbreviated" >href="mailto:[email protected]";>[email protected]</a> > > > >-------------------------------------------------------------------------------- >WISPA Wants You! Join today! ><a class="moz-txt-link-freetext" >href="http://signup.wispa.org/";>http://signup.wispa.org/</a> >-------------------------------------------------------------------------------- > >WISPA Wireless List: <a class="moz-txt-link-abbreviated" >href="mailto:[email protected]";>[email protected]</a> > >Subscribe/Unsubscribe: ><a class="moz-txt-link-freetext" >href="http://lists.wispa.org/mailman/listinfo/wireless";>http://lists.wispa.org/mailman/listinfo/wireless</a> > >Archives: <a class="moz-txt-link-freetext" >href="http://lists.wispa.org/pipermail/wireless/";>http://lists.wispa.org/pipermail/wireless/</a> >--- >[This E-mail scanned for viruses by Declude Virus] > > > </pre> > </blockquote> > <pre wrap=""><!----> >Wireless High Speed Broadband service from Info-Ed, Inc. as low as $30.00/mth. >Check out <a class="moz-txt-link-abbreviated" >href="http://www.info-ed.com/wireless.html";>www.info-ed.com/wireless.html</a> >for information. > > >-------------------------------------------------------------------------------- >WISPA Wants You! Join today! ><a class="moz-txt-link-freetext" >href="http://signup.wispa.org/";>http://signup.wispa.org/</a> >-------------------------------------------------------------------------------- > >WISPA Wireless List: <a class="moz-txt-link-abbreviated" >href="mailto:[email protected]";>[email protected]</a> > >Subscribe/Unsubscribe: ><a class="moz-txt-link-freetext" >href="http://lists.wispa.org/mailman/listinfo/wireless";>http://lists.wispa.org/mailman/listinfo/wireless</a> > >Archives: <a class="moz-txt-link-freetext" >href="http://lists.wispa.org/pipermail/wireless/";>http://lists.wispa.org/pipermail/wireless/</a> > > > </pre> ></blockquote> ><br> ><pre class="moz-signature" cols="80">-- >Jack Unger - President, Ask-Wi.Com, Inc. >Author - "Deploying License-Free Wireless WANs" >Serving the Broadband Wireless Industry Since 1993 ><a class="moz-txt-link-abbreviated" >href="http://www.ask-wi.com";>www.ask-wi.com</a> 818-227-4220 <a >class="moz-txt-link-abbreviated" >href="mailto:[email protected]";>[email protected]</a> > > > > > ></pre> ></body> ></html> >--- >[This E-mail scanned for viruses by Declude Virus] > > Wireless High Speed Broadband service from Info-Ed, Inc. as low as $30.00/mth. 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