Adaptive Two-Level Unequal Error Protection Convolutional Code Scheme for Wireless ATM Networks

Because the wireless asynchronous transfer mode (ATM) networks are often constrained with the limited link bandwidth and error prone characteristics, forward error correction (FEC) is needed to improve their bit error rate performance. In this paper, a two-level punctured convolutional code (PCC) scheme is constructed to apply to wireless ATM cell header and various payloads with the flexible unequal error protection (UEP). Since their perforation matrices can be programmable, the code rates of PCCs are applicable to the different sensitivity of source encoded symbols, even if only the same encoding and decoding hardware is used. Finally, the performance on Gaussian and fading channels is analyzed, which shows significant reductions in cell loss rate (CLR) and good balances for CLR and the payload bit error rate (BER).