Cognitive frequency hopping based on interference prediction
Stefan Geirhofer, John Z. Sun, Lang Tong, Brian M. Sadler · ACM SIGMOBILE Mobile Computing and Communications Review · 2009
Wireless services in the unlicensed bands are proliferating but frequently face high interference from other devices due to a lack of coordination among heterogeneous technologies. In this paper we study how cognitive radio concepts enable systems to sense and predict interference patterns and adapt their spectrum access accordingly. This leads to a new cognitive coexistence paradigm, in which cognitive radio implicitly coordinates the spectrum access of heterogeneous systems. Within this framework, we investigate coexistence with a set of parallel WLAN bands: based on predicting WLAN activity, the cognitive radio dynamically hops between the bands to avoid collisions and reduce interference. The development of a real-time test bed is presented, and used to corroborate theoretical results and model assumptions. Numerical results show a good fit between theory and experiment and demonstrate that sensing and prediction can mitigate interference effectively.