Adaptive Interference Cancellation: Cancellation Performance vs. Computational Overhead

Abstract

Superposition interference cancellation (SIC) has been highlighted due to its high spatial reuse efficiency in wireless networks. It exploits superposition aspect of multiple signals to cancel interferences. We present three basic SIC schemes, which are (1) superposition demodulation scheme, (2) superposition decoding scheme and (3) iterative superposition decoding scheme in this paper. When selecting an SIC algorithm among them, the computational overhead and cancellation performance have a trade-off relationship. In a fair communication environment, the receiver can save energy with little loss of cancellation performance by adopting a simple SIC algorithm, such as superposition demodulation. If the network condition looks bad, the node should apply a sophisticated SIC scheme, like iterative superposition decoding, to accommodate near-optimal performance of cancellation. Selecting a different SIC scheme in terms of network condition is called adaptive interference cancellation. The adaptive cancellation scheme draws fairly good interference cancellation performance with relatively low mean computational overhead to save energy consumption.