Abstract:

Considering the inter-carrier interferences (ICI) caused by in-phase and quadrature-phase (IQ) imbalances and multipath time-varying channels in orthogonal frequency division multiplexing (OFDM) systems through time-frequency doubly-selective channels, an IQ imbalances compensation scheme is proposed based on sphere decoding (SD) and parallel interference cancellation (PIC). By simplifying the system model and dividing it into several blocks, the SD algorithm is used to compensate the intra-block interference, while the PIC algorithm is used to mitigate the inter-block interference. These two algorithms are combined with several iterations. Simulation results show a good system performance of the proposed IQ imbalance compensation scheme.