Research On Spectrum Sensing Method Based On Wideband Digital Channel Receiver

In the context of the era of intelligence,various types of mobile Internet,Internet of Things devices and other frequency-using devices have shown explosive growth,resulting in an increasing demand for electromagnetic spectrum resources and a complex electromagnetic spectrum environment.However,according to domestic and foreign analysis,there is still a serious waste of spectrum resources.In addition,the form of modern warfare is changing in the direction of electronic information warfare.Nowadays,electronic information warfare is faced with a complex electromagnetic environment with strong interference and strong confrontation.How to use spectrum sensing technology to gain the dominance of electronic warfare in a complex electromagnetic environment has become an important game of great powers.means.Therefore,spectrum sensing technology in complex electromagnetic spectrum environment has become an important issue affecting national and social security and stability.Based on the national "13th five year plan" project,aiming at the spectrum sensing technology in the complex electromagnetic spectrum environment,this paper studies how to use the broadband digital channel receiver to meet the current spectrum sensing needs,and achieve large bandwidth,low delay,fast processing and high accuracy sensing.The system has high detection probability,good time and frequency resolution,and can meet the spectrum sensing of large bandwidth.Firstly,the general structure of the digital receiver is analyzed and the basic framework of the spectrum sensing system is designed.The digital channelized receiving algorithm is discussed,and the efficient structure of the uniform channelized receiver is derived.At the same time,the hot issues are discussed.A dynamic channelized design scheme is proposed for the cross-channel problem of broadband signals,and the simulation is completed.Finally,the spectrum sensing system is implemented with FPGA.The specific work completed is as follows:1.In view of the data processing requirements of spectrum sensing studied in this thesis,the technical advantages of digital channelized receivers are firstly analyzed,and the key technologies required for the realization of the receiver system are discussed.The digital channelized receiver implements the basic framework of the spectrum sensing system and designs the function of the hardware module.2.Aiming at the problem of digital channelization receiving algorithm in the system,first analyze the basic principle of channelization technology and the characteristics of channel division,and then derive an efficient structure based on poly phase filtering structure to achieve channelization through mathematical theory,and analyze the hot issues.Finally,the theoretical simulation of the channelized receiving system is carried out to verify the rationality of the channelized high-efficiency structure.3.Aiming at the cross-channel problem in the receiver structure,the basic technology to solve the cross-channel problem is firstly analyzed,and a dynamic channelization receiving algorithm based on the analysis-synthesis filter bank is proposed in combination with the actual problem,and the structure of the synthesis process in the algorithm is carried out.Then,the filter bank is approximated and completely reconstructed for the analysis and synthesis structure design.Finally,the dynamic channelization technique is simulated in MATLAB to ensure that employing the algorithm to address the cross-channel problem is proper.4.Complete FPGA hardware implementation and functional testing for system design.First,the system hardware selection is determined according to the hardware system design,and then the hardware code is written according to the system data processing flow,and then the frame structure and Ethernet communication link design is carried out for data transmission.The polling mechanism and command parsing method for uploading time domain and frequency domain data respectively are proposed.Finally,the function test of the network port and the whole system is carried out,and the performance evaluation of spectrum sensing is carried out.