Advanced signal-processing algorithms for energy-efficient wireless communications

Substantial progress has been made in the receiver signal-processing algori thms for wireless commmunications to minimise the requirements on signal-to -noise (and/or interference) power ratio and computational complexities for the same quality of service. In cellular infrastructure systems, one of th e key system design objectives is the base stations is to maximize the rece iver sensitivity, so that the required signal level from the mobile station s can be minimized. The use of advanced signal-processing algorithms, based on maximum a posteriori (MAP) estimation, iterative (turbo) channel estima tion, equalization, and decoding, allows for a reduction of the required tr ansmitter power by one-third to one-half. Lower computational complexities in the terminals, which implies a reduced power drain on the digital circui ts, can be achieved by using techniques that adapt the state complexity of the receiver to the propagation channel. We give an in-depth review of thes e algorithms, and discuss their performance and implementation requirements .