Abstract:

Shannon  indicated that any redundancy can be utilized to battle noise at the receiver. Since the constant bytes in data streams can be considered as redundancy, this paper investigates the utilization of constant bytes to help decoding in the system with selfsynchronization scrambling. An errorresilient scheme including several steps is proposed: first we extract information bits from the hard decisions of demodulator output and descramble them, then detect the const bytes and locate the errors in the descrambled data, and finally map the error positions back into the scrambled data and correct the corresponding errors before sending it into the channel decoder. Since this errorresilient process decreases the errors in data streams, the performance improvement after decoding is expected. The simulation results show that a gain of about 0.5 dB in signalnoise ratio can be obtained by utilizing the constant bytes at a payload rate of 30%.

Key words: errorresilient decoding;selfsynchronization scrambling;redundancy;constant bytes