Research And Realization Of RF Transceiver Front-end Based On P And L-band

Now, the application range of RF technology has developed very widely. With thedevelopment of modern military, national defence and wireless communication, highertechnical requirements are raised for RF transceiver front-end circuit in mobilecommunication, radio detection and guided weapons as well as electronic warfare systems.The P and L-Band working in0.23~2GHz is the most popular band in wirelesscommunications, and it can provides several demodulation methods but also broadbandintermediate frequency output. Therefore, based on the latest research achievements,research is conducted on the P and L-band RF transceiver front-end circuit in this paper.Firstly, aiming at the RF transceiver front-end circuit operating principle, amultiple-superheterodyne transceiver system solution is given by taking the circuitstructure and index requirements into consideration, the signal is dealt with severalfrequencies conversion, amplification and numerical control attenuation in order tomitigate the filter pressure, which is convenient to filter out clutter. Finally, theexperimental results showed the transceiver with this structure is easy to realize systemperformance indicators.Secondly, focusing on the RF transceiver front-end, the key modules of RFtransceiver system is designed in this paper. And the key modules include: frequencyconversion module, amplifier module, numerical control attenuator module, switchmodule and the frequency synthesis module. The schematic circuit of each module andits corresponding PCB layout are designed by PADS. The experimental results showedthat the key modules designed in this paper can satisfy the requirements; the designedphase-locked frequency synthesizer has the characteristics of low phase noise, spurioussmall, good stability and simple circuit structure.Finally, the RF signal transmission process in the printed circuit board is analyzedand the system hardware welding and debugging are completed. Additionally, the testingmethods and results of the RF transceiver’s gain control performance and varioustechnical indicators are given and explained in detail. The experimental results show that the RF transceiver front-end circuit in the paper has a wide range of gain controlling, atthe same time, it has a wide dynamic range, high sensitivity, good SNR and low phasenoise and all system indicators can meet the initial design requirements.