A Detection Algorithm for MIMO Transmission Using Poly-Diagonalization and Trellis Decoding

A MIMO decoding algorithm utilizing poly- diagonalization and tail-biting trellis is proposed. Linear MIMO decoding, such as zero-forcing equalization, is a channel diagonalization technique, where all interferences from other data streams are suppressed for separate decoding. It is well known, however, that such decoders suffer from the noise enhancement. In the proposed scheme, interferences are partially allowed, in order to alleviate the noise enhancement and, then, post trellis decoding is used for the joint detection utilizing the poly-diagonal structure of the effective channel. Under the proposed framework, the zero-forcing equalizer can be regarded as special cases of poly-diagonalization, i.e., of the first order. And the proposed scheme can provide a tradeoff between the complexity and performance by choosing an appropriate order of poly-diagonalization. According to the simulation results, considerable gain can be obtained even with the second order, i.e., bi-diagonalization, for which the decoding complexity is far less than that of the maximum likelihood decoding.