Hmm - On your first example with the STA, most of the low cost radios do not have very good RX levels so the increases power from the AP would help increase the reach in some cases and with the better RX levels on our radios this helps hear the TX from the remotes better. Again the system needs to be setup correctly but there any many times where the higher power will help.
- Next "Larger beam widths invite more interference", yes if not setup correct. But assuming you need to cover 120* and assuming there is interface, a higher power radio using a lower gain antenna will HELP a setup like this, because less noise gain from the antenna that reaches the RX of the radio and balancing the system. Again its all about the design. - Also I agree a higher gain radio does reduce the total EIRP, but this not a bad thing. For example a 300mW radio can have a max antenna gain of 15.6dBi which works out very good for the example I listed below. Again I am not saying use a 300mW radio all the time which is why we also have 100mW and 200mW again adding more tools to what people need AND are able to design system correctly. - One last point the high power radios fill a void where many people are using AMPS and do no need to, these radios offer a lower cost solutions to fill the void. Sincerely, Tony Morella Demarc Technology Group, A Wireless Solution Provider Office: 908-996-7995 Fax: 908-847-0202 http://www.demarctech.com -----Original Message----- From: Jim Thompson [mailto:[EMAIL PROTECTED] Sent: Wednesday, April 14, 2004 2:14 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: Re: [BAWUG] RE: 300mw? On Apr 13, 2004, at 10:19 PM, <[EMAIL PROTECTED]> wrote: > Jim > > I agree with you on a basic setup but if a system is engineered > correctly, its very easy to have a balanced systems. Note that the example I gave was about an AP with associated STAs. I assumed that the common case would be laptop/pda/phone like clients, unable (or unwilling) to support the 300/400mW cards, for a variety of reasons, including exposure limits. Therefore, the link will be greatly unbalanced. > The main benefit to a 300mW/400mW (soon) radio is a lower gain antenna > thus a larger vertical beam width at the base station, this is NOT the > best setup for all applications but it does add additional options to > the WISP tool box. Larger beamwidths invite more interference. You've also missed my point. First a couple of assumtions: 1) antennas with gains greater than 30dBi are for our purposes, too large to be practical. 2) People will adhere the FCC rules, (even if they don't have the system certified with the antenna and pigtails they're using, but I digress.) Check this out. mW dBm max dBi ptmp max dBi ptp EIRP 1000.0 30.0 6.00 6.00 36.00 794.33 29.0 7.00 9.00 38.00 630.96 28.0 8.00 12.00 40.00 501.19 27.0 9.00 15.00 42.00 398.11 26.0 10.00 18.00 44.00 316.23 25.0 11.00 21.00 46.00 251.19 24.0 12.00 24.00 48.00 199.53 23.0 13.00 27.00 50.00 158.49 22.0 14.00 30.00 52.00 125.89 21.0 15.00 100.00 20.0 16.00 79.43 19.0 17.00 63.10 18.0 18.00 50.12 17.0 19.00 39.81 16.0 20.00 31.62 15.0 21.00 25.12 14.0 22.00 19.95 13.0 23.00 15.85 12.0 24.00 12.59 11.0 25.00 10.00 10.0 26.00 7.94 9.00 27.00 6.31 8.00 28.00 5.01 7.00 29.00 3.98 6.00 30.00 Note that when running ptp, the allowed EIRP is higher for the lower power card. > Also aesthetics comes in to play many times where a small, clean > looking device unit is the only option, again the radio gain can be > the difference between a link working or not. #include <something about sacrificing performance for asthetics.h> (and I do actually agree with you when it becomes the primary concern). > Some of this may be outside the decision of this list but there are > valid reasons for these designs. Actually, so far, it all seems to be on-topic to me. > Sincerely, Tony Morella > Demarc Technology Group, A Wireless Solution Provider > Office: 908-996-7995 Fax: 908-847-0202 http://www.demarctech.com > _______________________________________________ BAWUG's general wireless chat mailing list [unsubscribe] http://lists.bawug.org/mailman/listinfo/wireless
