Adaptive subcarrier allocation for multiuser MIMO-OFDM systems based on imperfect feedback

An adaptive subcarrier allocation algorithm based on imperfect feedback was proposed for multiuser MIMO-OFDM systems with VBLAST architecture. Not only the feedback channel information, but also the feedback quality were considered in the algorithm. The definitions of confidence coefficient and equivalent variance were introduced to indicate the feedback quality, and the closed expressions were deduced in actual environments considering both feedback delay and feedback error. Simulation results show that the proposed algorithm can improve system performance in various imperfect feedback scenarios.