A DS-CDMA Interference Cancellation Technique for Body Area Networks

A low complexity Parallel Interference Cancellation (PIC) technique that is applicable to body area networks (BANs) is presented. Using Direct-Sequence Code Division Multiple Access (DS-CDMA), the technique aims at suppressing interference caused by rapid changes in relative sensors position due to body parts motion as well as interference from adjacent BANs. Interference signal is estimated using a relationship between cyclic correlation of the received signal and interferer code without requiring any knowledge of the channel condition. The codes for the multi-sensor DS-CDMA communication are constructed by using a set of m-sequences. The cyclic correlation is performed using Fast Walsh-Hadamard Transform (FWHT) which exhibits low computational complexity. In addition to low complexity, the proposed technique does not require complicated channel condition estimation and has no convergence issues. The uncoded Bit Error Rate (BER) performance of the proposed interference cancellation over a body-surface channel is calculated and compared with the conventional scheme.