Performance Analysis of Energy Detection with Multiple Correlated Antenna Cognitive Radio in Nakagami-m Fading

This letter analyzes the performance of energy- detection-based spectrum sensing in a cognitive radio (CR) possessing multiple correlated antennas when the channel from the primary user (PU) to the CR is Nakagami-m faded. The probability of detection of the CR by employing square law combining (SLC) is derived by using the MGF-based approach. Special cases of equally correlated, exponentially correlated and a linear array of 2, 3 and 4 arbitrarily correlated antennas are treated. Numerical and simulation results are used to quantify the detector performance as a function of antenna correlation across the branches, number of antennas, fading severity and the time-bandwidth product.