Based On The Spectrum Of Cycle Stationary Feature Perception Technology Research

With the rapid development of wireless communication technology and the growingnumber of wireless users, the spectrum resources is becoming serious shortage, whichhas became one of the bottlenecks restricting the development of wireless technology.While some bands, such as TV band, have not been rationally utilized, resulting in aserious waste of resources. In order to improve the spectrum utilization efficiency andsolve the problem of scarce spectrum resources, the cognitive radio (CR) technologyhas been proposed. By understanding the spectrum of the space environment, the CR isable to detect the spectrum holes that are not be used or in a low utilization, which canbe employed by the cognitive users. Therefore, the spectrum sensing technology is oneof the key technology and the most important prerequisite for the development ofcognitive radio.As one of the commonly used spectrum sensing technology of cognitive radio,Cyclostationary feature detection not only can detect if the authorized users exist in thenoise and be able to make it when other interfering signals present, which makes thespectrum sensing results of cognitive radio more accurate and reliable. As result, we canutilize the idle frequency bands fully and timely, which improve the spectrum utilization.Therefore, the spectrum sensing technology based on cyclostationary is the focus of thispaper.This paper studies the basic concept of second-order cyclostationary features ofcommunication signal and the commonly used estimation method of the spectralcorrelation function, such as: frequency smoothed method (FSM), FFT accumulationmethod (FAM) and strip spectral correlation analyzer (SSCA).In addition to, we havedeveloped some simulation and complexity analysis.In the study of spectrum sensing based on cyclostationary, we developed aninvestigation to the spectrum sensing form the cyclic autocorrelation function in thetime-domain and the spectral correlation function in the frequency-domain respectively,meanwhile we made some performance analysis and simulations to them and wecompared the simulation results to other detection method. We proposed the improved energy detection based on the cyclostationary according to the communication signal’scyclostationary and energy detection’s advantages, which has a better performancecompare to the traditional energy detection. In order to study the implement of signal’scyclostationary in the practical application we develop the hardware simulation in theDSP to FSM and we develop a sensitivity test about cyclostationary feature detection inorder to analyze its performance in the implement.We study the basic concepts of higher order theory of cyclostationary and analyzethe estimate method of cyclic moment and cyclic cumulants. And then we construct thespectrum sensing method based on the higher order cumulant theory of cyclostationarywith the asymptotically optimal theory and some simulation results are provided.