System Design Of Automatic Measurement Of Frequency Parameters For Analogous Circuit

With the development of science and technology in our country, the exploitation of ocean gradually takes people's attention. Frequency response test has extended to the maintenance and the calibration of the underwater acoustic equipment. The frequency characteristic of underwater acoustic equipment has been regarded. The system which had lots of characters, such as its adjustable measuring accuracy, stabilization and credibility, simple principle, manufacture and so on, had definite status in practice.The development of the state of spectrum analyzer at home and abroad and the basic method and principle were introduced in this paper. And in accordance with automatic measurement system of frequency parameters for analogous circuit performance, the overall design of the system was completed.The design primary intention lied in the design of automatic measurement system of frequency parameters for analogous circuit. The system determined the length of output waveform and data sampling frequency, referring to different testing bandwidth and precision, then completed the automatic sweep test. The system was connected through the RS232 to the computer. The system measured circuit's amplitude-frequency characteristic and phase-frequency characteristic. For multi-channel system, amplitude phase coherence was also tested, as well as isolation. The test upper frequency was 1MHz, mainly applied in the low frequency domain survey, such as acoustics and vibration.The system circuit divided into two parts of the digital and analog. The digital circuit used double CPU. FPGA chip (EP1C6Q240C8) was main controller, primary cognizanced data buffer, work order of each module and the test flow; DSP chip (TMS320VC5509A) was the slave processor, primary cognizanced data computation of system; Simultaneously, DDS chip (AD5930) was used to generate sweep signal for completing the system test. The analogous part included difference conversion network as well as ADC conversion circuit.The paper elaborated the system design and realizing in software and hardware. Lastly, the detailed discussion was made to the system hardware and the software debug, and the improvements were suggested in this thesis.