Design And Implementation Of S-band Miniaturized Telemetry Receiver

For the purpose of receiving and processing telemetry data of centralized aircraft test,a design of S-band miniaturized telemetry receiver is proposed to transform the measured performance of the test equipment into visual dynamic performance data.The main tasks of the receiver include accurately and reliably receiving telemetry signals during system test,frequency conversion,analysis,processing and data storage of the received telemetry signals,so as to provide real-time,accurate and reliable test means for the test equipment,so as to determine the performance of the test equipment or provide basis for equipment fault analysis.In the overall design,according to the design principle of superheterodyne receiver,the preselected filter is placed after low noise amplifier to improve the sensitivity of the receiver.In the frequency conversion design of the receiver,the method of twice mixing is mainly adopted,and the difference frequency signal is selected for both mixing.In the design of AGC,a novel three-stage gain control method is adopted to expand its dynamic receiving range.In the design part of local oscillator signal,10 MHz crystal oscillator is selected,which is divided into two 10 MHz signals through power divider,and then combined with their respective PLL circuits to generate the required first local oscillator signal and second local oscillator signal.The receiver takes S-band as the receiving signal and is built with mature components under the idea of modular and miniaturized product design.It has the advantages of strong portability and high throughput.In addition,in order to complete the simulation test of the whole system,baseband PCM simulation,if pcm-fm modulation and S-band up conversion unit are added to complete the RF simulation signal output,so that the whole system can complete its own closed-loop self-test without the help of external signal generator.Through the frequency point and sensitivity test of the receiver with external signal source and the closed-loop test of the receiver itself,it is verified that the receiver meets all the design indexes.The final conclusion is to complete the design of S-band miniaturized telemetry receiver and realize the reception,frequency conversion,demodulation and synchronization of S-band RF signal.In the specific implementation,according to the technical indicators of each module,select the corresponding components,draw the schematic diagram and layout the PCB layout,so as to achieve the realization of the hardware circuit.These steps have been repeatedly verified to improve the realizability and reliability of the S-band telemetry receiver.Through this design,the characteristics of large dynamic,multi frequency and high sensitivity of telemetry receiver are realized,and the development and test of hardware are completed.