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To: S100 who wrote (66661)	2/14/2000 2:26:00 AM
From: engineer	Respond to of 152472

I have no idea what your babling about. the spacing of the edges is on 30 khz boundries, but that is only because we choose that since there were all these nice analog tuning systems out there. but the basic chipping rate is 1.2288 Mhz and this means that it COVERS the entire 1.2288 MHZ space. Put in some guardbands on the edges and you get exactly 1.25 Mhz envelope. Each channel is exactly 1.2288 MHZ wide and overlays the next one. Think of it more like layers of paper over each other, each of a different color. Each channel looks like noise to the other one, so it rasies the noise floor that each demodulator sees. Each CDMA channel ocupies the EQUIVALENT of so many 30 khz channels. You are in fact not limited to just 41 channels in the system, but rahter to a noise level that your reciever and transmitter can tolerate. IF you have a fixed WLL type system and you can spend a long time on the best estimate of power control, then you can raise the level up to 55 channels or so. If you have perfectly orthogonal noise, such as HDR uses where you modulate all 64 channels at once, you can use all 64 Walsh channels. The point was not so much that we needed an entire systems deisgn course in CDMa systems, but rahter that for someone who claims to be an RF engineer at a basestation, he is awfully naieve about how the system really works, so myself I would place a grain of salt next to his post. there are far more things which limit the system than the carrier settings. Bad phones in suffceint numbers can also mess with the system and this is why the carriers are so stringent on testing hte phones for RF quality. this is why phones like MOT and NOK don;t make it into the system and this is exactly what KYO bought from QCOM. the RF testing and qualification ability. As for Ruffian (Mike) , I think he is confused as to what and who he is posting to.