Optimal coding rate of punctured convolutional codes in indoor wireless TDMA cellular systems

The microcellular link performance of future multimedia indoor wireless systems could be improved by using error-correcting punctured convolutional codes in conjunction with slow frequency hopping. However, the bandwidth expansion due to coding leads to a decrease in the signal-to-interference ratio of a FD-TDMA cellular radio link if system capacity is to be maintained for a given bandwidth allocation. This work determines the best compromise between the power of error correction due to coding and the strength of the self-induced system interference, in terms of numerous criteria for speech and data transmission. The aforementioned trade-off is evaluated in terms of the average bit error rate and the burst error distribution for voice transmission. For data transmission with a selective-repeat ARQ protocol, the criteria are throughput, round-trip acknowledgement transmission delay and buffering requirements at the transmitter and receiver. The study clearly highlights that punctured codes can significantly improve performance for indoor wireless data links in comparison with the rate 1/2 convolutional coding case or the no-coding case.<
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