Toward Expanded Wi-Fi Access in the 5 GHz Band

Wi-Fi is critical to the nation’s wireless broadband goals, by some estimates carrying more than half of all Internet traffic. However, robust Wi-Fi growth risks a wireless capacity shortage, and the latest mass- market Wi-Fi technology, known as 802.11ac, is constrained by inadequate spectrum access. The FCC has proposed to expand Wi-Fi access in the 5 GHz band to address these issues.The 5 GHz Wi-Fi band is shared with several other services. This paper analyzes the interference risk to certain incumbent services posed by expanding Wi-Fi access, with a particular focus on two sub-bands known as UNII-1 and UNII-4. We find that interference analyses submitted by incumbent interests are faulty and substantially overstate the risk of interference. We demonstrate how accurate analysis illustrates many potential paths to coexistence between Wi-Fi and incumbent services. We also suggest areas for further research to this end, with the goal of preserving and enhancing the high consumer benefits of Wi-Fi.