DeMiLTE: Detecting and Mitigating LTE Interference for Enterprise Wi-Fi in 5 GHz

LTE in unlicensed 5 GHz bands is being deployed by mobile operators for increased capacity. In this paper, we conduct an extensive measurement study with commodity LTE and Wi-Fi hardware to identify key coexistence challenges. Our study -- the first to include a commercial LAA base station -- confirms that LTE interference causes WiFi performance to degrade, harming 802.11ac high-throughput features. We then present DeMiLTE -- a system for commodity enterprise WiFi APs that detects, quantifies, and reacts to LTE interference. To our best knowledge, our solution is the first that achieves fair coexistence without modifying the LTE PHY/MAC, while still being fully-compliant to the 802.11ac standard. DeMiLTE's architecture is based on lightweight per-link interference detection and enables WiFi APs to mitigate LTE-induced performance degradation with minimal overhead. Our evaluation results show that DeMiLTE can provide up to 110% throughput gains and alleviate client disruption caused by LTE interference.

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