Iterative bit & power allocation for V-BLAST based OFDM MIMO system in frequency selective fading channel

Abstract

This paper presents an iterative bit and power allocation algorithm for an OFDM multiple-input multiple-output (MIMO) system in frequency selective fading channels and uses V-BLAST as a detection algorithm. Assuming knowledge of the instantaneous channel gains for all spatial channels at all the subcarriers in the receiver, bit and power is assigned to each spatial channel to minimize the total transmission power for a fixed bit error rate (BER). We demonstrate by computer simulation that the proposed iterative bit and power allocation algorithm can significantly improve the system performance compared to the traditional V-BLAST and singular value decomposition (SVD) algorithm for an OFDM MIMO system in a frequency selective fading channel model.