Study On Broadband Spectrum Sensing Algorithm Based On Compressed Sensing Of L-DACS1

In view of the future demand for large-capacity high-speed transmission of aeronautical communications,European Organization for the Safety of Air Navigation(EURO-CONTROL)together with Federal Aviation Administration(FAA)proposed the L-band Digital Aeronautical Communication System(L-DACS)as a ground-to-air communication system for future aeronautical communications,L-DACS including L-DACS1 and L-DACS2 two candidate technology solutions.L-DACS1 has more attention than L-DACS2,which has higher spectrum efficiency,more flexible spectral selectivity and scalability.At present in the L-band has been deployed tactical air missile system,Distance Measurement Equipment(DME)system,joint tactical information release system and other avionics systems,L-DACS1 will transmit the spectrum interval of the DME system by the discontinuous interpolation method,and how to determine the use of the existing DME spectrum becomes the most important problem in the actual deployment of L-DACS1.Therefore,this thesis focused on the DME broadband signal spectrum sensing problem of L-DACS1.The spectrum sensing problem is still an open issue which has not been standardized at present,solving it can provide the support for the standard formulation and practical deployment of L-DACS1.The DME signal is a broadband multi-band signal.At present,the current utilization of the system is low,and the DME signal show a strong sparse nature in the frequency domain.If the traditional broadband spectrum sensing technology is used to separate,the multiple frequency bands need to be separate perception.It not only limits the sensing ability,but also makes this method difficult to apply to the actual system because of high hardware complexity and cost.Based on this,this thesis will use the broadband sensing technology based on compression sensing to deal with it.The Modulated Wideband Converter(MWC),which is used to replace the analog to digital converter can greatly reduce the demand for hardware,and realize the sub Nyquist sampling of wideband signal.However,the existing broadband spectrum sensing algorithm is mainly for the general broadband signal and the perceived performance is poor,directly applied to L-DACS1,there will be many problems.Therefore,this thesis will conduct an in-depth study of this issue.The specific studies include:(1)Aiming at the problem of poor perception of DME signal by the existing broadband spectrum sensing algorithm,this thesis proposes a broadband spectrum sensing algorithm based on the existing multi-band signal broadband spectrum sensing algorithm.In this thesis,this thesis use the column vectors joint information in the Multiple Measurement Vector(MMV)problem and the spectral characteristics of the DME signal as the support set extension conditions to find more potential support sets.Calculate the pseudo inverse matrix can obtain a more accurate DME frequency domain support set,which can effectively improve the spectrum sensing performance of DME signal.(2)In MATLAB software,the thesis uses the Monte Carlo experiment to verify the traditional algorithm Orthogonal Matching Pursuit(MMVOMP),Reduce MMV and Boost(ReMBo)and the algorithm proposed in this thesis DME MMV and Boost(DMEMB)algorithm.The simulation results show that the proposed algorithm is superior to the traditional algorithms in aspects of the success rate of spectrum sensing,the minimum number of tests for successful spectrum sensing and the maximum sparse degree of successful spectrum sensing.