New automatic error control system with ATM cell header reduction for wireless ATM networks

Abstract

In this paper we introduce a new error control system for wireless asynchronous transfer mode (WATM) networks. The new system is based on using a new scheme to reduce the ATM cell header size before applying the multiple error correcting Bose-Chaudhuri-Hocqenghem (BCH) code instead of the usual header error control (HEC) for the wireless portion of the transmission. This new scheme implies dividing the ATM cell header into segments, then comparing all segments with the first one to generate reduced length codes to represent the compared segments. The result of applying the new technique for the wireless portion of the network is a reduced header length which has an advantage in reducing delay while maintaining the required cell loss probability limit. The newly suggested system is also an automatic system with respect to the level of BCH encoding. When the bit error rate (BER) is high, the system increases its error correction capability and vice versa. Realistic multi-path fading error patterns were analytically approximated and applied to evaluate the system performance. The results show that the new system achieves an encoding delay which is considerably less than the encoding delay of a fixed BCH system with 3 error correction capability and an original HEC system, while maintaining the required limit of cell loss.