Joint Estimation of Channel and IQ Imbalance in Media-Based Modulation

In direct conversion radio frequency (RF) front-end architecture, RF impairments such as IQ imbalance (IQI), DC offset, flicker noise, and oscillator leakage can affect the performance. In this work, we study the performance of media-based modulation (MBM), an attractive channel modulation scheme, in the presence of transmit and receiver side IQI and propose efficient compensation techniques. MBM is shown to be more resilient to IQI compared to conventional modulation. A scheme which jointly estimates and compensates the channel and IQI parameters using widely linear least squares estimation is proposed. The proposed scheme is shown to alleviate the transmit and receive IQI-induced BER degradation in MBM.