Research And Implementation Of Spectrm Sensing System Based On FPGA-Based Software Radio Platform

Cognitive radio technology is an effective way to solve the current spectrum problem of resource constraints and underutilized situation. As a core technology of cognitive radio, the spectrum sensing can sense the surrounding spectrum environment to look for spectrum holes for the communications needs of users. These paper studied and implemented a spectrum sensing software radio platform system based on FPGA and AD-FMCOMMS1RF board, proposed a blind spectrum sensing energy detection algorithm for broadband scene of600MHz～3.0GHz, and did the algorithm theoretical analysis and simulation. The algorithm is applied in the spectrum sensing system and get good performance.The main work and innovation of this paper is as follows:1. This paper proposed a broadband spectrum sensing energy detection algorithm based on iteration, the algorithm can achieve the energy detection and judgment of the entire2.4GHz bandwidth signal with optimum performance. The simulation results show that when the SNR is greater than-1, the misjudged rate is steady at0.1or less.2. This paper designed and implementated a spectrum sensing software radio platform system based on SOC system, including the RF drive and control subsystem based on AD-FMCOMMS1, RTL-level baseband signal processing subsystem, the control system of SOC based on the Microblaze, the control and data transmission subsystem based on Linux C++, and the subsystem of achieving broadband energy detection and final display based on MATLAB.3. The system used the method of multiple sweep and spectrum stitching to complete the spectrum sensing for signal in the frequency range of600MHz～3.0GHz, achieving a major breakthrough in the overall performance. The ADC sampling rate in RF front-end is 163.84Msps, the baseband signal processing unit is running stably at200MHz clock, once single spectrum sensing has a bandwidth of60MHz, with an ultra-fine spectral resolution10kHz. After the actual verification, the system can complete more than10times spectrum sensing per second for the2.4GHz band frequency signal, and display the results of spectrum sensing and energy detection in real time on the front end.