BER analysis of IQ imbalance compensation for GFDM systems

Abstract

As one of the 5G waveform candidates, generalised frequency division multiplexing (GFDM) systems have been proposed to achieve lower out of band radiation and stronger robustness against synchronisation errors. However, theoretical BER performances of GFDM systems with in‐phase/quadrature (IQ) imbalance, as well as compensation strategies, have not been widely investigated. In this Letter, the authors evaluate theoretical BER performances of GFDM systems with transmitter IQ imbalance (IQI) before and after a proposed compensation method. Basically, they give approximated BER expressions for different modulations through considering introduced IQI completely as useless interference, and then derive a more precise BER expression for QPSK modulation. Additionally, they put forward a compensation method to remove IQI interference in GFDM systems at the cost of enlarged noise. Furthermore, analytical BER expressions with IQI compensation are derived, and then the effectiveness of the proposed compensation strategy is proven by theoretical and simulation results.

Performance analysis of space time coded generalized frequency division multiplexing system over generalized fading channels

“…A lot of work has been done in the area of GFDM system primarily focused on implementation of GFDM, performance improvisation using pulse shaping filters and the employment of STC‐GFDM system 6‐27 …”

“…In Reference 13, the approximate BER expressions of GFDM system is derived considering the inphase/quadrature (IQ) imbalances at the transmitter end of the system. Thereafter, a compensation method is also introduced to reduce the IQI interference but at the cost of the enlarged noise.…”