A Soft-Decision Demodulator for WBAN Systems Using Stochastic Computing

Wireless body area network (WBAN) is an efficient fundamental technology for medical and healthcare applications. Soft decision receiver is attractive for the reason that the performance gains result in significant transmitting energy reduction. However, the soft decision demodulation (SDD) for π/4-DQPSK modulation specified in IEEE 802.15.6 standard suffers from high complexity and power consumption. Stochastic computing is a promising low hardware cost and low power consumption implementation candidate. In this paper, a novel stochastic computing based soft decision demodulation method is proposed to achieve low complexity and low power demodulation. According to the evaluation results, the proposed design utilizes advantages on hardware cost and power consumption with respect to the existing SDD schemes. In addition, the proposed design supports prior probability input, demonstrating a potential for turbo-like iterative receiver for WBAN systems to further improve the performance.