Wideband spectrum sensing based on group testing utilizing polyphase filter banks

A wideband spectrum sensing procedure based on the idea of group testing is proposed in this paper. A new polyphase filter bank (PFB) for which the output subbands have the same bandwidth and contain continuous frequency components is proposed. This PFB is utilized to form a two-stage wideband spectrum sensing method. The simulations show that the proposed method can reduce the number of binary tests greatly when the number of occupied primary channels is low.

I. Introduction

Cognitive radio [1] [2] has been proposed as a solution to the spectrum underutilization problem by opportunistically accessing the currently unused spectrum licensed to primary users (PUs). Because cognitive radios are considered as secondary users (SUs) of the spectrum, they should not cause harmful interference to PUs. To reach this goal, SUs need to sense a wide spectral range to detect spectrum holes for communications. This process is referred to as wideband spectrum sensing.