Constant-modulus Preamble Design for MIMO-OFDM Systems

A new preamble design for MIMO-OFDM is proposed in this paper. Based on the Chu sequence, the proposed preamble can be used to achieve frequency offset estimation, fine time offset estimation, and optimal least-squares channel estimation. In addition, since the preamble has constant modulus, it has low peak-to-average power ratio. Furthermore, channel estimation can be done through simple phase and magnitude justification, and enjoys low computational complexity.