Research On Key Technology Of X-Band High Power T/R Module Based On LTCC Technology

Transmit/Receive module(T/R module)is an important part of antenna front-end of synthetic aperture radar and active solid-state phased array radar.It is responsible for signal amplification and phase adjustment.The performance of T/R module determines the quality of signal reception and transmission.With the continuous development of modern military technology,more microelectronic technologies has been applied to the development of radar.The T/R module made by microelectronic technology has the characteristics of light weight,small volume,good performance,high reliability and modularization.It is widely used in various military and civil radar systems,such as airborne,satellite-borne and missile-borne synthetic aperture radar,round active solid-state phased array radar,civil vehicle radar,hand-held radar,etc.Multi-chip module technology(MCM)is a common method of microelectronic assembly technology.It can integrate many different types of electronic systems to reduce volume,improve performance and improve overall reliability.And low temperature co-fired ceramic technology(LTCC)has the characteristics of small size,light weight,low cost and short processing cycle,which is the most widely used technology.And T/R module based on LTCC technology is the trend of modern radar system.This paper mainly studies the following works:Firstly,the main methods and characteristics of LTCC technology are summarized.The base material and conductor material system of LTCC process are introduced.And the basic process of LTCC process as well as the common integrated components and module packaging methods in LTCC process is given,which lays a technical foundation for the design of T/R module in the future.Secondly,the transmission performance of microstrip line,power divider,gold wire bonding line and transition structure of microwave port microstrip line are simulated and analyzed by using three-dimensional electromagnetic field simulation software ADS and Ansoft HFSS.By optimizing the structure and size,desired microwave transmission characteristics of the microstrip line are obtained in X-band.Then a circulator based on LTCC technology is designed by using simulation and optimization of software Ansoft HFSS.The operating frequency of the circulator is9800-10200MHz.Within the working frequency band,the isolation degree of the circulator is greater than 25dB.The insertion loss is less than 1Db.The echo loss is greater than 25dB.And the LTCC substrates with different thicknesses(0.5mm to 2mm)can maintain desired transmission performance.Finally,an X-band high power transceiver module based on LTCC technology is developed.The desiging of T/R module include the analysis of component design indicators,devices selection,structure design,thermal simulation and scheme demonstration.Then the module processing,assembly and component testing are completed.The LTCC substrate is fabricated by the low temperature co-fired ceramic process line of the 55th Research Institute of China Electronics Technology Group Corporation.The assembly and testing of the components are completed by Nanjing Guobo Electronics Company Linited.The X-band T/R module operates at frequencies of 9.8-10.2 GH z,with a transmission branch gain of 30 dB and an output power of 40 dBm(10W).In the whole working frequency band,the gain of the receiving branch is 23 dB and the noise figure is less than 10 dB.The size of the whole assembly T/R module is 73×50×14 mm~3.In this paper,the development process of X-band high power T/R module based on LTCC technology is described in detail.Finally,the problems in the design and fabrication process are summarized and the future research is prospected.