Multi-User Spectrum Sensing for Cognitive Radios: Trace and Eigenvalues Approach

In this paper, we propose a novel spectrum detection method for cognitive radios using covariance matrix eigenvalues and its trace. Unlike some traditional eigenvalue and covariance-based detectors, the proposed method is independent of noise power and computationally simple. An optimal threshold calculation approach is also proposed based on the statistical characteristics of the test statistic. This threshold optimization improves detection reliability under different signal-to-noise ratio (SNR) conditions. This common usage improves detection reliability, especially under low SNR conditions and limited sample sizes. Theoretical analyses are provided in detail to characterize the statistical behavior of the proposed test statistic for both hypotheses. Detailed simulation results show that the proposed method is advantageous in terms of computational cost and detection performance. © 2013 IEEE.