Design And Realization Of High Power Microwave Multiplexer

High power wireless communication system are applied widely in remote sensing communication and power transmission , it needs increasingly strict requirement in both passive intermodulation(PIM) interference and selectivity in channels. As the rapid development of modern microwave communication technology , communication frequency has been increasingly density , also multichannel communication system needs two or more directions real-time communication,all these put forward new requirements to the multiplexer. The multiplexer which is composed of coaxial-cavity filter with generalized Chebyshev function has the characteristic of low insertion loss,small volume,high restraintion in stop-band,both it and passive intermodulation are the researchful focus at present.The paper not only described the design method of conterminous pass-band multiplexer,but also it researched and designed importantly microwave triplexer of non-conterminous pass-band . Based on design requirement of triplexer , the triplexer circuit was designed and simulated in Microwave Office after getting parameters by bringing in transmission zero according to generalized Chebyshev function.On the implement of microwave structure , this paper designed the band-pass filters of GSM channel,DCS channel and WCDMA channel with coaxial-cavity,and it also simulated fesonant frequency,coupling coefficient with HFSS to get the scantling of structure and made layout of triplexer with volume requirement.After layout the respective ports and the public port were designed according to time delay value and the triplexer was debugged after matching the several ports.At last this paper designed testing systems and tested PIM power from three channels respectively based PIM testing principle.The results showed that the designed triplexer can meet low insertion loss,high restraintion in stop-band and big power capability,also the PIM results meet the requests.