Research And Implementation Of Spatial Spectrum Sensing Algorithm

With the rapid development of the wireless communication technology,the contradiction between the increasing spectrum demand and limited spectrum resources has become increasingly prominent.The cognitive radio technology is an effective way to solve the current shortage of spectrum resources and low utilization rate.Spectrum sensing is the most critical technology for cognitive radios.This technology greatly improves spectrum utilization and alleviates the increasingly strained spectrum utilization.This paper studies the spectrum sensing technology and implementation methods in cognitive radio.Firstly,the paper introduces the background and development status of the cognitive radio technology and spectrum sensing technology.Then the paper studies the existing spectrum sensing technology,and the advantages and disadvantages of the existing spectrum sensing methods are compared and analyzed.Based on that analysis,we choose the energy detection algorithm to achieve the spectrum sensing system.Besides,the article carries out the theoretical analysis and simulation verification of the algorithm,the hardware implementation framework of spectrum sensing system based on energy detection algorithm.Also,this paper highlights the FPGA design implementation and verification process of the digital baseband signal,which mainly includes the design and implementation of the parallel down-sampling low-pass filter.,the design and implementation of the parallel FFT transform module and the design and implementation of energy calculation module.Finally,the paper simulates the performance of the entire system and analyzes the differences in perceived time and resource usage between serial and parallel implementations.The verification result is consistent with the design goal.The system can correctly detect the occupancy of the frequency band.The main work and innovation of this article are as follows:(1)The paper proposes a spectrum sensing hardware implementation framework based on energy detection algorithm after studying the existing spectrum sensing algorithms,besides,the paper also builds an FPGA-based hardware implementation platform and gives the hardware platform simulation and test results.(2)The paper proposes a parallel implementation architecture on the basis of the traditional serial implementation architecture by the deployment algorithm.Through this technology,the system sampling rate is increased to 1Gsps,which enhances the system's digital signal processing capabilities and shortens the system's perceived time.This topic is based on the development of the Kintex-7 series chip of Xilinx Company.It is programmed with Verilog HDL hardware description language.The development environment is Xilinx's ISE14.7 and Mensim Graphics' Modelsim simulation software.