MIMO transceivers with decision feedback and bit loading: theory and optimization

This paper considers MIMO transceivers with linear precoders and decision feedback equalizers (DFEs), with bit allocation at the transmitter. Zero-forcing (ZF) is assumed. Considered first is the minimization of transmitted power, for a given total bit rate and a specified set of error probabilities for the symbol streams. The precoder and DFE matrices are optimized jointly with bit allocation. It is shown that the generalized triangular decomposition (GTD) introduced by Jiang, Li, and Hager offers an optimal family of solutions. The optimal linear transceiver (which has a linear equalizer rather than a DFE) with optimal bit allocation is a member of this family. This shows formally that, under optimal bit allocation, linear and DFE transceivers achieve the same minimum power. The DFE transceiver using the geometric mean decomposition (GMD) is another member of this optimal family, and is such that optimal bit allocation yields identical bits for all symbol streams--no bit allocation i...

• Type: Journal
• Year: 2010
• Where: TSP
• Authors: Ching-Chih Weng, Chun-Yang Chen, P. P. Vaidyanathan
• Keywords: Artificial Intelligence, Bit Allocation, Optimal Bit Allocation, Optimal Family, TSP 2010