An error protected 16 kbit/s voice transmission for land mobile radio channel

Robust speech coding and an efficient error correction coding is indispensable for toll-quality voice transmission in mobile radio because of degradation due to multipath fading. A decision procedure for the bit-selective forward-error-correction (BS-FEC) scheme is proposed as a promising solution to this problem, and backward-type prediction speech coding is shown to be more robust against transmission errors than forward-type prediction. Combinations of BS-FEC (channel coding) and backward-type prediction speech coding are designed, and improvements in the SNRs of transmitted voice signals are examined. Simulation results show that BS-FEC can provide good speech quality even at a bit error rate (BER) of 10^-2 in Rayleigh fading environments, at the cost of a slight degradation in the SNR (signal-to-noise ratio) at low BERs