An Adaptive MIMO Decoder

In existing MIMO systems, either optimal or sub-optimal decoders can be used according to the required performance. However, the optimal decoders give ML performance but have very high complexity and the sub-optimal decoders give low complexity but poor performance. Moreover for ML decoding, the variable decoding time at a fixed SNR for the different channel realizations and also the big gap in the complexity between low and high SNRs represent a critical point for practical implementation. We propose here an adaptive decoder that allows to switch between optimal and sub-optimal decoders according to the channel realization and the system specifications. This decoder offers an almost constant complexity while keeping good performance.