Probabilistic data association for wireless passive body sensor networks

摘要: Passive communications based on modulated backscatter can dramatically extend the lifespan of wireless sensor networks. Because passive networks reduce dependence batteries, they have great potential to be used in body sensing applications. In a typical network deployment, multiple nodes modulate common carrier. The superimposed reflected signals resolved by using code division access (CDMA) principles. practical systems however, strong carrier component will leak receiver, causing offset constellation points and as result it destroy cross correlation properties CDMA codes. To address this problem, we propose shift modulation instead vanilla CDMA. We develop maximum likelihood receiver analyse its performance. Since complexity ML detection strategy scales exponentially with number sensors, reduced technique Probabilistic Data Association (PDA). demonstrate via numerical simulations that our detector approaches