Time-Frequency Multiplex Estimator and Low Complexity Equalizer Design for Multi-Carrier Systems with TX/RX IQ Imbalance, CFO and Multipath Fading Channels

A low complexity time-frequency multiplex estimator and low complexity equalizer transceiver design is proposed to combat the RF impairment problems for the zero-IF transceiver of multi- carrier systems. Moreover, the proposed preamble can estimate and compensate the transmitter/receiver (Tx/Rx) in-phase and quadrature-phase (IQ) imbalance, carrier frequency offset (CFO), and channel impulse response parameters. There are two parts in the proposed system. Firstly, all parameters of impairments are estimated by the proposed time-frequency multiplex estimator design. Secondly, the estimated parameters are used to equalize the above problems and detect the transmitted signal with low complexity advantage. Simulation results confirm that the proposed estimator can provide reliable performance over the severe Tx/Rx IQ imbalance, CFO, and multipath fading channel environments.