Throughput Analysis of MRT-ZF Wireless Body Area Network with Multi-Antenna AP

摘要

This paper analyzes the throughput performance in a wireless body area network (WBAN) consisting of a multiantenna access point (AP), which intends to broadcast radio frequency (RF) power to several single-antenna on-body sensors then receives physiological information from them. Different path loss and shadowing values are considered in channel models between AP and sensors to be more reliable. In this paper, we design an improved time-splitting protocol which is adaptive according to channel conditions. The whole protocol is divided into two parts: power broadcasting phase and information receiving phase. In power broadcasting phase, the AP broadcasts RF power to sensors using maximal ratio transmission (MRT) method. In the information receiving phase, the AP receives information from all sensors simultaneously after sensors harvest RF energy in last power broadcasting phase, and zero-forcing (ZF) method is applied when the AP decodes information. In each time block, considering signal to noise plus interference power ratio (SINR) threshold, the sum information throughput is formulated as a relative entropy problem subject to the timesplitting ratio constraint. We propose the optimal solution to this problem, and numerical results demonstrate the effectiveness of the optimal time-splitting ratio.