Title: "An Efficient Detection of Primary Users Reoccupation in Cognitive Radio Systems By Active Sensing "
         

Page(s): 70 - 74
Authors: A.Suhanya,RS.Koteeshwari

Abstract

In the past years, fixed spectrum assignment policies worked well. But today, due to the rapid increase in number of users in mobile communication as well as in other communication areas, arises a problem called 'spectrum scarcity'. It can be solved by developing a new communication paradigm that will use the existing spectrum efficiently. It is achieved with the help of cognitive radio. One of the main functions of the cognitive radio is spectrum sensing. In this paper, Spectrum sensing is carried out by Quite-Active sensing. In that, active sensing is carried out by spectral correlation function which is one of the cyclostationary feature detection with non-cooperative detection. Here, known pilot signals from the primary users base station are duplicated and reallocated in cognitive radio users modulating signal. The spectral correlation is carried out between the cognitive radio user and primary users. With the help of Spectral correlation function, we can efficiently detect the primary users reoccupation in cognitive radio systems. It will provide higher security because the pilots are added with the cognitive radio users modulating signal. Here 52 ofdm samples, 2 primary users and 4 bit pilots are used. And the simulation is carried out with the help of matlab and their results show the effectiveness of proposed approach.

Index Terms—Active sensing, Cognitive radio, Cooperative detection, Cyclostationary feature detection, Quiet – Active sensing, Spectral correlation.