Performance Analysis of Uplink IM-OFDMA Systems in the Presence of CFO and Rx-IQI

Index modulation-based orthogonal frequency division multiple access (IM-OFDMA) has been recently proposed as a promising candidate for future wireless communication systems due to its superior spectral efficiency and error performance compared to conventional multiple access schemes. Therefore, it has been under investigation by researchers analyzing its performance considering different scenarios and assumptions. Following this direction, this paper presents the error performance of the uplink IM-OFDMA in the presence of carrier frequency offset (CFO) and receiver (Rx) in-phase and quadrature imbalance (IQI). In particular, the individual and joint effects of the CFO and Rx-IQI on the bit-error-rate (BER) performance of the uplink IM-OFDMA scheme are investigated, and then the IM-OFDMA is compared with the conventional OFDMA scheme by considering the detrimental effect of CFO and Rx-IQI. Accordingly, this paper shows that IM-OFDMA achieves better BER performance results than the OFDMA scheme in the presence of CFO and Rx-IQI. However, the obtained results also reveal that the IM-OFDMA scheme is very sensitive to RF impairments even though it performs better than conventional OFDMA.