Impact of Ultra-Narrowband Interference on Wi-Fi Links: An Experimental Study

• Published in: IEEE transactions on wireless communications Vol. 20; no. 5; pp. 3016 - 3030
• Main Authors: Mahfouz, MHD Zaher, Kokkeler, Andre B. J., Meijerink, Arjan, Glazunov, Andres Alayon
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.05.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: 2.4 GHz ISM band; 2.4GHz ISM band; Communications systems; Interference; Jamming; Methodology; Modulation; Narrowband; On-Off Keying; Sensors; Subcarriers; Throughput; UNB; Wi-Fi; wireless coexistence; Wireless communication; Wireless fidelity; Wireless sensor networks; WSN
• ISSN: 1536-1276; 1558-2248; 1558-2248
• DOI: 10.1109/TWC.2020.3046765

We develop a systematic methodology to experimentally investigate the impact of interference from a non-listen-before-talk ultra-narrowband (UNB) signaling technique on Wi-Fi links. The methodology is based on a worst-case interference scenario, and consists of three investigating steps. This methodology is then applied to a measurement setup to practically study the case of 100 bps UNB signals interfering with an IEEE 802.11n transmission in the 2.4GHz band. Five different Wi-Fi devices are tested. The UNB signal is generated in two modulation schemes, the on-off-keying (OOK) and the Gaussian minimum-shift-keying. Both single and multiple simultaneous UNB interferers are considered. An analysis of the measurement results shows that three of the tested Wi-Fi devices cannot coexist with the considered non-listen-before-talk UNB communication system. The throughput performance analysis of the other tested devices shows that the OOK-modulated UNB signal has the least interfering impact, and the Wi-Fi pilot subcarriers are the most vulnerable to UNB interference. However, if a single UNB interferer avoids these subcarriers and employs the OOK-modulation scheme, then wireless coexistence is possible as long as the signal-to-interference ratio of Wi-Fi to UNB is greater than 30dB, given that a drop to 75% of the maximum Wi-Fi throughput is acceptable.