Performance of Unequal Error Protection Schemes for Audio Transmission Over ADSL with Reed Solomon and Turbo Codes

摘要

This paper performs a comparative analysis of Unequal Error Protection (UEP) schemes for audio transmission over Asymmetric Digital Subscriber Line (ADSL). The proposed UEP scheme exploits three different levels of protection. First at the Discrete Multi-tone Modulation (DMT) layer, second with prioritized retransmissions and finally by using different code rates. A comparative analysis between Reed-Solomon (RS) codes and Turbo Codes is performed using two different block sizes. For the Turbo codes, Sign Division Ratio (SDR)-based extrinsic information scaling is also applied to further enhance the performance. Results show that when UEP is applied at three different levels, a gain of 11 dB is obtained over a scheme which applies UEP at only two levels.