Joint Detection of Correlated OFDM Subchannels for Wideband Spectrum Sensing in Cognitive Radio Networks

In this paper, we consider the wideband spectrum sensing in which primary users use OFDM modulation. Pulse shape of each subchannel is non-ideal which results in the leakage of power among adjacent subchannels. This phenomenon makes the received energy of each subchannel (test statistic of energy detector) correlated with those of other subchannels. Therefore, in order to jointly detect the state of primary network subchannels, we propose a simple iterative method and we observe its performance improvements in comparison to the disjointed method (in which the detection of each subchannel state is independent of the detection of others.