Research And Design Of 300MHz-18GHz Ultra-wideband Miniaturized Transmitter

With the continuous development of wireless communication technology,the requirement of miniaturization and high integration of wireless communication system is increasing day by day.As an important part of wireless communication system,transmitter is responsible for amplifying and transmitting communication signals.In this paper,based on Laminated Multi Chip Module(MCM-L)technology and Microwave Integrated Circuit(MMIC)technology to realize the miniaturization of transmitter system,the 300MHz-18 GHz UWB miniaturization transmitter is designed and implemented.First of all,after fully investigating the relevant references of integrated radio frequency transceiver systems at home and abroad and analyzing the expected design indicators,this paper has carried out a detailed scheme design of the 300MHz-18 GHz ultra-wideband miniaturized transmitter system,including the structure and system of the transmitter.The selection of frequency conversion scheme and the design of transmitter system including intermediate frequency channel,radio frequency channel and power drive channel,and used ADS simulation software to simulate and evaluate some important parameters of the transmitter system,including link clutter and gain and gain flatness simulation.Secondly,the chip selection of the integrated devices in the system was carried out,and the passive structure was miniaturized designed: mainly including the ultra-wideband vertical interconnection structure,two intermediate frequency filters and radio frequency segmented filters.Among them,the 8.5GHz low second intermediate frequency filter adopts a microstrip hairpin filter;the 22 GHz high second intermediate frequency filter adopts a multi-layer SIW filter based on cross-coupling;in order to reduce the number of radio frequency segmented filters and facilitate the miniaturization of the system,a switch filter bank chip is selected to realize the segmented output of radio frequency signals.Finally,according to the system design plan,the layout design of the transmitter's radio frequency circuit and power control board and the design of the cavity structure of the whole machine are completed,and the whole machine assembly is completed through the microassembly process.The final machine size is about 12cm×4.5cm×1.5cm.The whole machine was tested,and the test results showed that the output signal frequency covers 300MHz-18 GHz,the output power reaches 24 d Bm,the gain reaches more than 44 d B,the gain flatness is less than±1d B,and the suppression of in-band and out-of-band harmonic clutter is up to above 50 d Bc,the output power of the whole machine has a dynamic adjustable range of 24 d B,and the output voltage standing wave ratio is less than 2.0,which meets the index requirements.