Vhf Band Channel Module Development

In recent years, radio communication technologies are developing at amazing speed, especially UHF radio which is applied widely in military and civil communication and provides high research and development value.This thesis derives from CETC-10's XX Type UHF Radio project, of which channel module is developed by writer. Channel module includes receiver, transmitter RF front-end, frequency synthesizer, and interface control unit. Using superheterodyne second frequency conversion, this module receiver design is composed of LNA, tuned filter, mixer, IF amplifier circuit and AGC control circuit to implement large dynamic range receive technical criteria. Transmitter RF front-end performs RF signal excitation and amplification after they are up-converted from IF signals to provide enough excitation power for PA and ensure power proportionality in all bands. Frequency synthesizer provides stable LO signal for T/R channel. Interface control unit performs control of whole module.Focused on channel module design, its basic principle and key technologies are studied and discussed and a VHF channel module is successfully developed, based on many reference documents on VHF channel module and T/R module designs in China and abroad.In this paper, several structures of transmitters and receivers are compared at first, and key technical parameters of T/R channel are discussed. Then module hardware design is proposed and its specifications are demonstrated. Detail circuit design and implement methods are introduced, and module test results are provided. For problems founded in test, deep analysis is performed and practical resolutions are proposed.