SS-CDMA flexible wireless network: approximately synchronized CDMA modem for uplink

摘要

We have proposed an intracell uplink of an SS-CDMA flexible wireless network based on an approximately synchronized (AS) CDMA. The AS-CDMA features no co-channel interference during a guard-chip duration. A sequence with the guard-chip duration can be designed using pseudo periodic method and the orthogonal frequency multi-channel method. The uplink without co-channel interference dose not require the complete transmission power control (TPC), which is indispensable in the conventional systems such as IS-95. The AS-CDMA modem has been designed and implemented for Japanese 2.4GHz SS band. Using the implemented AS-CDMA modem, the BER performance of 4ch multi-transmission has been measured. The degradation of E{sub}b/N{sub}0 at a BER of 10{sup}(-3) is 3.5 dB, and the desired-undesired signal power ratio (DUR) is -8dB.