Optimum band allocation according to subband condition for BST-OFDM

Abstract

This paper proposes and investigates optimum band allocation scheme and modulation assignment for band-segmented transmission OFDM (BST-OFDM) according to different environment characteristics of each segmented band or subband channel. The proposed system can adaptively optimize the allocation of subbands according to a conditional parameter, that is, the CNR under independently fading subband channels. The optimization criterion is the minimum total BER performance under the constraint conditions that are the total bandwidth, the number of subbands and the constant total information bit rate. The subband condition is updated by the feedback information from the receiver. The proposed adaptive band allocation BST-OFDM system can overperform the conventional BST-OFDM system in which subbands are divided with equal bandwidth.