Summary
International Workshop on Smart Info-Media Systems in Asia
2022
Session Number:SS1
Session:
Number:SS1-5
A Low Complexity Carrier Frequency Offset Compensation for Full-Duplex with Cooperative MIMO in IEEE 802.11 WLAN
Muhammad Harry Bintang Pratama, Leonardo Lanante Jr, Hiroshi Ochi,
pp.21-26
Publication Date:2022/9/15
Online ISSN:2188-5079
Summary:
Self-interference cancellation is an important technology to achieve full-duplex communication. The self-interference in IEEE 802.11 network can be suppressed using Cooperative Multiple Input Multiple Output (Co-MIMO) applied null beamforming. This method requires a weight matrix that is obtained from the Channel State Information (CSI). However, residual CFO among the access points (APs) will impact the calculated CSI, making it harder to suppress the self-interference in a wireless hardware implementation. In this paper, we propose a low complexity method for addressing the CFO problem in joint transmission when a direct connection and common clock are not applied to the APs. We evaluate the SI cancellation of the proposed method and show the experimental results using field-programmable gate array (FPGA) and software-defined radio (SDR). In addition, we also examine the change in CFO over time. Our results show that the proposed CFO compensation has a similar performance as a system where APs share the same clock (i.e. perfect carrier frequency synchronization) in terms of interference cancellation.