Ensuring self-coexistence among IEEE 802. 22 networks is a challenging problem owing to opportunistic access of incumbent-free radio resources by users in co-located networks. In this study. we propose a fully-distributed non-cooperative approach to ensure self-coexistence in downlink channels of IEEE 802. https://www.spidertattooz.com/OPI-GelColor-The-Color-That-Keeps-On-Giving-0-5-oz-HPJ07-p22791/