Spectrum Detection Technology Based On Power Spectrum For Compression Sensing

In recent years,the rapid development of various radio communication services makes spectrum resources increasingly nervous.Cognitive radio adopt dynamic spectrum access technology,actively look for and use non-hold authorized spectrum resources,it solves the current fixed spectrum allocation system caused by the problem of shortage of spectrum resource utilization.Spectrum sensing is the key technology of cognitive radio which reflects the essence of cognitive problems.Because most of the cognitive radio works over a wide frequency range,the traditional narrow-band signal detection technology is limited to apply in broadband spectrum perception.We need to study from the perception of real-time and reliability requirement.Efficient broadband spectrum sensing is a prerequisite for cognitive radio applications,so this paper depth studies this issue.First of all,this paper introduces the basic concept of cognitive radio and its key technologies,and summarizes the research status of spectrum at home and abroad.This paper introduces the main detection methods of the technology of spectrum sensing:receive detection,transmitter detection and collaborative spectrum sensing,etc.This paper focuses on the power spectrum detection,details the power spectral density function and several methods of the power spectral detection.Traditional signal detection methods in broadband signal have a high sampling rate by detection applications.Then the compressed sensing technology can effectively reduce the sampling rate and alleviate the pressure of A/D device and DSP processors.The realization of the rapid and accurate signal reconstruction is the key link in compression sensing.In view of the uncertainty noise has a low sensitivity,and a long testing time.This paper proposes power spectrum detection based on compression sensing.Combined with autocorrelation properties of sparse signal compress and sample,the algorithm can detect signals spectrum with low sampling rate in the uncertain noise environment.The simulation results show that:in the BPSK and MSK modulation,the method can accurately detect the primary user spectrum.In the low SNR,increasing the compression ratio improve detection performance.Finally,the presence of a single threshold detection algorithm for high false alarm rate and other issues,this paper proposes the dual-threshold detection based on the power spectrum.The simulation proved that this method can effectively utilize the power spectrum detection technology,and improve the spectrum utilization further,and significantly improved the probability of false alarm and detection probability in single threshold detection,be able to quickly and accurately capture the radio signal propagation channel at low SNR.