Despite the promising role of orthogonal frequency-division multiplexing (OFDM) in communication systems, the optimal and practical spectrum sensing of OFDM signals for cognitive radio systems over multipath fading channels remains an important and challenging issue. This paper presents the Neyman-Pearson detection scheme of OFDM signals employing continuous pilot subcarriers. Since there are many unknown parameters in the Neyman-Pearson detector to be resolved, we also present a generalized log-likelihood ratio test (GLRT) spectrum sensor. The considered problem is complex and leads to a joint detection and estimation problem. The proposed GLRT spectrum sensor only needs received samples. Moreover, the proposed GLRT spectrum sensor is robust to the frequency selectivity of fading channels and symbol timing offset and carrier frequency offset. Simulations confirm the advantages of the proposed detector.
All Science Journal Classification (ASJC) codes
- Computer Science(all)
- Materials Science(all)