Fpga-based Broadband Signal Parameter Measurement Method

Coining from a practical research project, this research task is concerned with the IF signals produced by the front end of a millimeter-wave high-sensitivity receiver after down-conversion, and the primary form of these IF signals are broadband narrow-pluses. The measurement methods of both the pulse frequency and the pulse width of these broadband narrow-pulses are studied extensively. In addition, the design of the measurement circuit is carried out and the measurement accuracy meets the requirement.The parameter measurement methods which are on the basis of FPGA technology are discussed in this paper. Combined with the actual situation, the scheme of digital phase-shift counting based upon FPGA is adopted after the analysis and comparison of different frequency measurement methods. Due to the fact that the system can achieve a very high counting frequency when the digital clock management module is employed to realize frequency multiplication and phase shift, the whole system can reach high measurement accuracy. Based on the operational theory of digital phase-shift counting, the method of measuring both the pulse frequency and pulse width of broadband narrow-pulses at the same time is proposed here. During the specific realization, the PFGA of Spartan-3-XC3S400 produced by Xilinx and the software platform of ISE 9.0 are adopted. Then the compilation by means of Verilog HDL and simulation through ISE Simulator are carried out.The design of the system is outlined firstly, and then every functional module is complied and simulated. Finally, the whole system is simulated successfully. Moreover, the AVR MCU is employed as the complementary module which completes the functions of interruption control, data processing and LCD display.