Energy-efficient cooperative spectrum sensing using rateless coded relaying

We consider cooperative spectrum sensing in a cognitive radio network where multiple nodes exchange their sensing information over wireless links. Although sensing in a cooperative manner improves detection reliability, it comes at the cost of a significant overhead in terms of reporting energy and delay. As a means of reducing this overhead, we propose an energy-efficient cooperative sensing scheme, at the heart of which lies rateless coded relaying coupled with an efficient user selection criterion that incorporates the scheme´s rateless coded nature. Through simulations, we show that for the same detection performance, a scheme based on fixed-rate codes utilizes 62% more energy and 15% higher delay compared to that with the proposed rateless coded relaying strategy.