Smart antenna systems have been studied for many years for signal detection and estimation and are used only in
military applications until recently. These are becoming popular from recent years and are used in commercial
applications due to impulsive advancement in the digital signal processing and VLSI technology. In array signal
processing, plethora of problems related to signal detection and estimation is solved using various Direction Of Arrival
(DOA) algorithms, including Bartlett, Maximum Likelihood Method (MLM), and Maximum Eigen Value (MEV) method.
These algorithms and many variants of these algorithms deteriorate from its performance either for narrow angle or
wide angle separation. Hence the authors proposed the DOA estimation algorithm based on Hannan-Quinn (HQ)
criterion for wideband spectrum sensing in cognitive networks. Simulation results validate the effectiveness of this