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Guys,what is the purpose of Walsh codes on the forward Cdma link? sagitraz 21-April-2008 08:47:18 AMComments www.freepatentsonline.com/WO2004114553.html Posted by crouse urpose is 64 othoronal Walsh codes per sector to identify channels (S/N is not infinite due to AWGN, multipath, and the neighboring cell) Posted by waqqas1 1. The forward link consists of up to 64 logical channels (code channels). 2. Code channels is one of a set of 64 so-called Walsh functions. Purpose is 64 othoronal Walsh codes per sector to identify channels (S/N is not infinite due to AWGN, multipath, and the neighboring cell) Long code (period 2 42 -1) to scramble data DS at 1.2288 Mcps 4. Every cell uses the same PN sequence (period 2 15 or 26.67ms) and is identified by a pre-defined offset (64 x n chips) 5. Coherent QPSK demodulation Diversity 6. time diversity: coding + interleaving path diversity: soft handoff and RAKE receiver Posted by Andy08 |
Posted: 28-April-2008 09:55:08 PM By: Andy08 1. The forward link consists of up to 64 logical channels (code channels). 2. Code channels is one of a set of 64 so-called Walsh functions. Purpose is 64 othoronal Walsh codes per sector to identify channels (S/N is not infinite due to AWGN, multipath, and the neighboring cell) Long code (period 2 42 -1) to scramble data DS at 1.2288 Mcps 4. Every cell uses the same PN sequence (period 2 15 or 26.67ms) and is identified by a pre-defined offset (64 x n chips) 5. Coherent QPSK demodulation Diversity 6. time diversity: coding + interleaving path diversity: soft handoff and RAKE receiver | |
Posted: 31-December-2008 12:31:09 PM By: waqqas1 urpose is 64 othoronal Walsh codes per sector to identify channels (S/N is not infinite due to AWGN, multipath, and the neighboring cell) | |
Posted: 14-June-2009 12:16:49 PM By: crouse www.freepatentsonline.com/WO2004114553.html |