On Max-SINR Receivers for HMT Systems Over a Doubly Dispersive Channel

In this paper, a novel receiver for hexagonal multicarrier transmission (HMT) systems based on a maximizing signal-to-interference-plus-noise ratio (Max-SINR) criterion is proposed. Theoretical analyses show that there is a timing offset between the prototype pulses of the proposed Max-SINR receiver and a traditional projection receiver. Meanwhile, the timing offset should be matched to the channel scattering factor of a doubly dispersive (DD) channel. The closed-form timing offset expressions of the prototype pulses for the Max-SINR HMT receiver over the DD channel with different channel scattering functions are derived. Simulation results show that the proposed Max-SINR receiver outperforms the traditional projection scheme and obtains an approximation to the theoretical upper bound SINR performance. Consistent with the SINR performance improvement, the bit error rate (BER) performance of the HMT system has been also further improved by using the proposed Max-SINR receiver. Meanwhile, the SINR performance of the proposed Max-SINR receiver is robust to the channel delay spread estimation errors.