Cooperative energy detection scheme for cognitive radio using RSTC

The objective of this paper is to design a spectrum sensing scheme using the concept of cooperative diversity and to implement Randomized Space Time Coding (RSTC) scheme for reducing the information overhead. The most important aspect in cognitive radio is spectrum sensing where the secondary user is able to access the spectrum of the primary user in the absence of the latter. Hidden terminals act as a source of interference by producing false information whereas the use of conventional Space Time Block Codes (STBC) increases the control information overhead. The proposed technique which uses cooperative communication for spectrum sensing and RSTC for cooperation between the relay nodes promises to solve the above mentioned problems. Simulation results obtained using MATLAB illustrate the effectiveness of the scheme over the conventional methods.