| The receiver front-end,considered as an important part of radar system, mainly accomplishes the amplification,filter,gain control and frequency conversion of the radar echo signals from the feed line.Some crucial characteristics of radar receiving system such as high sensitivity,large dynamic range and high out band suppression are realized in the receiver front end.Most of the modern airborne radar receiving system generally adopts twice frequency conversion mode.This paper presents the study on the production of a new-style airborne radar front-end,which works at X-band with 800MHz bandwidth.The difficulty of this work is to design a microstrip filter with 800MHz bandwidth and to select two L0 frequcencies.For the multi-function and high-integration of the front-end,MMIC or modular circuit are applied in Voltage variable attenuator,low noise amplifier,digital attenuator,mixl,if amplifier and mix2.The achievements research can be directly applied to the airborne radar products,and make the helpful exploring for the receiver front-end miniature, multi-function,reliability and stability.This paper introduces the development and application of the gradually mature MCM technology with LTCC technic,and puts forward the design of a minized full X-band front-end with LTCC technic.Finally,the actualization of the circuits and some analysis of the test data are refered. |
