Cooperative Relay Communication Performance under Spectrum-Sharing Resource Requirements

We propose using cooperative relaying technique in spectrum-sharing systems to more effectively and efficiently use the available transmission resources, such as power, rate and bandwidth, while adhering to the spectrum-sharing resource requirements of the licensed (primary) user. Specifically, we consider that the secondary user of the spectrum is assisted by a decode-and-forward (DF) relay to help in the communication between its source and destination nodes. In this context, we obtain the end-to-end performance of the proposed spectrum-sharing cooperative relaying system in terms of the average symbol error rate (SER) of the secondary's communication under appropriate constraints on the interference power at the primary receiver. We further analyze our theoretical results through simulations and comparisons illustrating the SER performance of the proposed spectrum-sharing cooperative system for different operating scenarios.