Aiming at the problems of high complexity and power consumption in hardware implementation of soft demodulation algorithm for π/8-differential 8-phase shift keying(π/8-D8PSK)modulation in wireless body area network(WBAN)

a soft demodulation system based on probabilistic calculation is designed.In this system

the probabilistic calculation mode is utilized to transform the phase change probability into random bit streams

and the complex operation is changed into simple logic gate circuits

which reduces the hardware complexity and power consumption

and the board-level verification of the scheme is realized on field programmable gate array(FPGA)using Verilog hardware description language.MATLAB simulation results show that the scheme can achieve the same performance as the hard-decision demodulation when uncoded

and the performance is improved by about 1dB when applied to the BCH soft-decision decoding system under BCH coding conditions.In addition

due to the simple logic structure

the design can meet the requirements of low complexity and low power consumption of the WBAN system

and it can be used as the demodulation module for the wireless transmission of human physiological parameters in the WBAN system.