An Analog-Filtered OFDMA Design for Receivers Utilizing One-Bit ADCs in Wideband Channels

Abstract

One-bit analog-to-digital converters (ADCs), despite introducing non-linear distortion, achieve capacity similar to high-resolution ADCs in low and moderate signal-to-noise ratio (SNR) scenarios over narrowband wireless channels. However, their integration with discrete Fourier transform based orthogonal frequency-division multiple access (OFDMA) systems is challenging due to discrete-time signal processing degradation, especially at moderate and high SNR regimes. To address this, we propose a method that integrates an analog low-pass filter (LPF) with one-bit ADCs to improve compatibility with OFDMA systems while mitigating non-linear distortion. Our approach presents an efficient solution for wideband multicarrier communication systems, optimized through simplified detection, optimal LPF bandwidth selection, and investigation of optimal detection time. The proposed scheme significantly outperforms conventional digital-domain OFDMA systems, provided that an ideal analog LPF is used. Even with a first-order LPF, it achieves comparable performance to deep learning-based systems when both use one-bit ADCs, despite its simplified structure.