A new channel estimation method using phase-shifted pilot sequence for MIMO-OFDM systems

In this paper, we propose a new MIMO-OFDM channel estimator with a phase-shifted pilot (PSP) sequence to enhance the performance and overcome the problems of conventional schemes. The proposed scheme overcomes conventional PSP estimator's limitation of requiring a uniformly distributed pilot position and performs better by adopting a minimum mean square error criterion that cannot he applied to conventional schemes. The proposed PSP channel estimator can perfectly separate multiple channel impulse responses, even though all transmit antennas use the same pilot position. Furthermore, the simulation results show that the performance of the proposed scheme is close to lower bound of the mean square error.