A cognitive radio must detect the presence of primary user to avoid interference. Spectrum sensing helps to detect the spectrum holes (unutilized bands of the spectrum) providing high spectral resolution capability. Different spectrum sensing techniques for cognitive radio are discussed in this paper. | ISSN:2249-5789 Partha Pratim Bhattacharya et al, International Journal of Computer Science & Communication Networks,Vol 1(2), 196-206 A Survey on Spectrum Sensing Techniques in Cognitive Radio Anita Garhwal and Partha Pratim Bhattacharya Department of Electronics and Communication Engineering Faculty of Engineering and Technology Mody Institute of Technology & Science (Deemed University) Lakshmangarh, Dist. Sikar, Rajasthan, Pin – 332311, India 1 2 anitagarhwal@ hereispartha@ Abstract The limited available spectrum and the inefficiency in the spectrum usage necessitate a new communication technology, referred to as cognitive radio (CR) networks. The key characteristic of CR system is that it senses the electromagnetic environment to adapt their operation and dynamically vary its radio operating parameters. A cognitive radio must detect the presence of primary user to avoid interference. Spectrum sensing helps to detect the spectrum holes (unutilized bands of the spectrum) providing high spectral resolution capability. Different spectrum sensing techniques for cognitive radio are discussed in this paper. opening (hole) is available. Thus to resolve the spectrum inefficiency problem, the concept of dynamic spectrum access and cognitive radio is introduced. These dynamic techniques for spectrum access are known as Cognitive Radios (CR). The concept of CR as proposed by Mitola in 1998 may also be defined as a radio that is aware of its environment and the internal state and with knowledge of these elements and any stored pre-defined objectives can make implement decisions about it. 1. Introduction Demand of radio spectrum is increasing day by day due to increase in wireless devices and applications. Current radio spectrum allocation is not efficient due to regulations that have limited spectrum access, spatial restriction on frequency usage. Peak traffic planning causes temporal under utilization since spectrum demand vary with time. A cognitive .
