Impact of carrier frequency offset and in-phase and quadrature imbalance on the performance of wireless precoded orthogonal frequency division multiplexing

Abstract

<p>Precoding in orthogonal frequency division multiplexing (OFDM) system proved to reduce the peak-to-average power ratio (PAPR), so that it improves BER. However, from the existing literature, the effect of carrier frequency offset (CFO), in-phase and quadrature (IQ) imbalance on precoded wireless OFDM systems has not been carried out. Therefore, this study evaluated the precoded OFDM (P-OFDM) system performance by considering the impact of CFO and IQ imbalance. P-OFDM performance evaluation is expressed in signal-to-interference noise ratio (SINR) and bit error rates (BER). The communication channels used are the additive white Gaussian noise (AWGN) channel and the frequency-selective Rayleigh fading (FSRF) channel, while the channel equalization process is considered perfect. The results of the analysis and simulation show that P-OFDM is greater affected by the presence of CFO and IQ imbalance than conventional OFDM system. In AWGN channel, P-OFDM experiences different SINR for each subcarrier. This is different from conventional OFDM system, where all SINRs are the same for all subcarriers. In the FSRF channel, both the POFDM system and the OFDM system experience different SINR for each subcarrier, where the SINRs fluctuation in the P-OFDM system is much larger than in the OFDM system.</p>

Evaluation of orthogonal frequency‐division multiple‐access systems in the presence of carrier frequency offset using wireless images transmission

“…The proposed approach involved estimating the CFO using a backward prediction system and then employing two types of filters—zero‐forcing and linearly constrained minimum variance—to suppress MAI based on the CFO estimates. The performance of the precoded OFDM (P‐OFDM) system was evaluated by investigating the impacts of CFO and in‐phase and quadrature (IQ) imbalance in [18]. The study was conducted using two different communication channels, the additive white Gaussian noise (AWGN) channel and the frequency‐selective Rayleigh fading (FSRF) channel.…”

“…FIGURE18 MSE results for interleaved system over SUI3 and QPSK. MSE, mean square error; SUI, Stanford University Interim.…”