Power allocation for OFDM-based relay cognitive radio system

Abstract

In this paper, we develop an optimal power allocation algorithm for the orthogonal frequency division multiplexing(OFDM)-based relay cognitive radio systems. The channel capacity of secondary users is maximized while keeping the total interference introduced to primary user less than a given threshold with a specified power. Compared with the other power allocation algorithm, the proposed method can achieve greater channel capacity and has a lower complexity.