Heterogeneous In-Band Full-Duplex System for Simultaneous SUN-FSK Transmission and SUN-OFDM Reception

Abstract

This study proposes a heterogeneous in-band full-duplex system for the simultaneous transmission of the existing wireless smart ubiquitous network (Wi-SUN) using IEEE 802.15.4g-compliant frequency-shift keying for smart utility network (SUN-FSK) and reception of the next-generation Wi-SUN using IEEE 802.15.4-2020-compliant orthogonal frequency-division multiplexing for SUN (SUN-OFDM). In particular, we propose a digital self-interference (SI) cancellation scheme based on high-precision SI channel estimation using the moving average method, which can be used when the SI signal is a SUN-FSK signal and the desired signal is a SUN-OFDM signal. Furthermore, we propose a highly efficient SUN-OFDM demodulation technique that considers the effect of residual SI. We evaluate the proposed methods through computer simulations. The proposed methods can achieve 67 dB of SI cancellation in the digital domain when the SI signal power and desired signal power ratio in the digital domain is 50 dB. The results of this study enable more efficient coexistence of the existing and next-generation Wi-SUNs, which is expected to improve the throughput and responsiveness of next-generation Wi-SUN systems employing SUN-OFDM.