Performance of different multi-rate schemes in DS/CDMA systems
نویسندگان
چکیده
In this paper the performance of different multi-rate schemes in Direct Sequence Code Division Multiple Access (DS/CDMA) systems are evaluated. The assumptions are random code sequences and AWGN channel. We have looked at four different solutions: different spreading factors, mixed modulation, parallel channels and Parallel Combinatory Spread Spectrum (PC/SS). Our conclusion is that parallel channels is the best scheme in supporting many data-rates, if we also take into account code-design and receiver complexity. Finally we suggest a combined system with parallel channels and mixed modulation, which is currently evaluated.
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