Spectrum Sharing Between A Surveillance Radar and Secondary Wi-Fi Networks

TL;DR

This paper investigates spectrum sharing between a primary search radar and secondary Wi-Fi networks, focusing on interference management, protection regions, and impact on Wi-Fi throughput in shared 3-GHz spectrum.

Contribution

It formulates the spectrum sharing problem, computes protection regions for single and multiple secondary users, and analyzes interference effects on Wi-Fi throughput.

Findings

Protection regions depend on secondary user distribution.

Interference impacts Wi-Fi throughput based on distance to radar.

Analytical framework for coexistence in shared spectrum.

Abstract

Co-existence between unlicensed networks that share spectrum spatio-temporally with terrestrial (e.g. Air Traffic Control) and shipborne radars in 3-GHz band is attracting significant interest. Similar to every primary-secondary coexistence scenario, interference from unlicensed devices to a primary receiver must be within acceptable bounds. In this work, we formulate the spectrum sharing problem between a pulsed, search radar (primary) and 802.11 WLAN as the secondary. We compute the protection region for such a search radar for a) a single secondary user (initially) as well as b) a random spatial distribution of multiple secondary users. Furthermore, we also analyze the interference to the WiFi devices from the radar's transmissions to estimate the impact on achievable WLAN throughput as a function of distance to the primary radar.