Design and Performance Verification of Time-Domain Self-Interference Estimation Technique for DOCSIS 3.1 System with Full Duplex

Abstract

In the full duplex communication environment, the transmitted downstream is inserted to the reception antenna as feedback self-interference (SI). The inserted SI signal is distorted by various distortion factors such as time/frequency offset, fading channel, and sampling time offset (STO). Therefore, to remove the SI signal, the distortion factors should be estimated and compensated. Furthermore, to perform the SI cancellation (SIC) in frequency domain, complicated synchronization process between received upstream and SI signal is required. In this paper, time-domain self-interference estimation (SIE) technique is proposed for DOCSIS 3.1 system with full duplex. The proposed technique estimates the distortion factors of SI signal in time-domain. Furthermore, to verify the estimation performance, hardware-based SI signal which is captured by DOCSIS 3.1 hardware platform with full duplex function is used. According to the test results, it can be shown that the proposed SIE scheme accomplish about 30dB MER performance through hardware-captured stream. Since the proposed technique is performed in time-domain, complicated synchronization process between upstream and SI signal is not required.