OFDM Closed-Loop Transmit Diversity Combined with Adaptive Power Allocation
Li Wei; Zhang Xiao-pin; Zhang Min;Ye Pei-da
Key Lab of Optical Communication & Light Wave Technologies, Ministry of Education, Beijing University of Posts and Telecommunications, Beijing 100876, China
Abstract：How to allocate power to antennas and carriers is a key problem when adaptive power allocation method is used to multi-antenna and multi-carriers Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system. In this paper, a novel algorithm for allocation of power is proposed. The algorithm firstly combines OFDM with closed-loop transmit diversity technique, then allocates the power to carriers to minimize the Bit Error Rate (BER). This algorithm has the optimum performance which has been proved by mathematical method. To the two transmitted antennas and one received antenna system when the number of OFDM subcarriers are equal to 4, simulation results show that there is 6.5dB gain by comparing with the traditional OFDM-STBC method at the BER of 0.1%.
2007, Vol. 29 
