Design And Realization Of Remote Measurement Sound Pressure Spectrum Analysis Device

As an important part of the space vehicle system,telemetry systems play an irreplaceable role in the development of aircraft.The enormous volume of flight space noise data and the limited information that can be monitored by the telemetry system in a fixed period of time due to data bandwidth limitations.How to break through the limitation to achieve efficient transmission of telemetry data is the focus and difficulty of the research.This thesis designs a telemetry sound pressure level spectral analysis device based on 1/3 octave spectral analysis theory,which fulfils the capabilities of noise signal acquisition and real-time time-frequency conversion of on-board data,greatly compressing the amount of data sent to the telemetry channel and essentially solving the problem of the pressure of flight noise parameters on the capacity of the telemetry channel.The functional requirements of the telemetry sound pressure level spectral analysis device are first investigated,a hardware circuit realization scheme is devised on the basis of an FPGA and DSP dual processor architecture,and the core devices are selected and designed.The structural design is briefly described in accordance with the requirements for miniature design of the device.The next step is the detailed design of the important interface circuits of the telemetry sound pressure level spectral analysis device,including the system power supply design,acquisition interface circuit design,data communication interface circuit design and CAN FD interface circuit design.The key technology of the telemetry sound barrier spectroscopy unit is the sound pressure spectroscopy algorithm and the real-time transmission between the FPGA and the DSP: the sound pressure level spectrum algorithm is designed based on the 1/3 octave spectrum analysis theory and MATLAB is used to demonstrate the integrity of the algorithm;the real-time transmission between the FPGA and the DSP is guaranteed by the transfer protocol and communication reliability design.Finally,a test platform was built to verify the functionality of the hardware circuitry.After confirming that the system power-up timing meets the design specification,the functional verification of the device is completed according to the sound pressure level spectrum verification method in the Kinetic Data Processing Guidelines,proving the rationality and feasibility of the telemetry sound pressure level spectrum analysis device design.Several tests have proved that the telemetry sound pressure level spectral analysis device can complete the real-time spectral calculation of noise data,satisfy the design function requirements and various performance indicators,and work in a stable state.