Design And Implementation Of Telemetry Data Recording Device

The telemetry data recording device studied in this paper is mainly used in the core position of an aircraft.The telemetry data recording device is composed of an editor and a memory.It is divided into function modules,and can be divided into acquisition,storage,and transmission modules.The acquisition module is integrated in the acquisition device for collecting key parameters during flight;the storage module is integrated in the memory for storing the collected data;and the transmission module is configured to transmit the data in the memory to the data processing system effectively and completely.This paper firstly designs the overall scheme of the data recording device,and then the corresponding scheme design is made for each functional module according to the functional requirements and technical indicators.Secondly,starting from the hardware design,the analog signal is conditioned,and the low-pass filter and voltage follower are added to reduce noise interference effectively.The digital isolation and command transmission circuit are designed by using the magnetic isolation 422 chip,and the impedance matching design of the 422 interface is analyzed.We design two data transmission links,LVDS and Hotlink for different devices,and describe the layout rules of the LVDS differential signals used for data transmission in detail between the encoder and the memory are elaborated on the PCB.Then from the logic design of the embedded software,the analog acquisition logic,digital reception logic,Flash storage logic and data transmission logic are described in detail,and the over-sampling and averaging filtering techniques are used to improve the accuracy of data acquisition.The data feedback retransmission protocol of the CRC check improves the reliability of data transmission.Finally,a ground test bench for testing the functions of the data recording device was built,and a comprehensive functional test was performed on the data recording device.I verify the accuracy of data acquisition,the reliability of data storage and data transmission through a large number of harsh environmental tests.Above all design indicators fulfill thedesign requirements.