Research And Design Of Non-reflective Filter Based On Silicon Substrate

With the continuous development of 5G communication,the requirements for RF circuits have also become higher,and the performance of the filter directly determines the quality of the RF circuit.The reflectionless filter absorbs the energy of the stop-band signal,avoiding adverse effects on other parts of the circuit and improving the performance of the entire circuit.The integrated passive device(IPD)technology of high-resistance silicon substrate is to grow a metal on a high-resistance silicon substrate to form a capacitor and other components to realize the design of passive components.It can meet the requirement that the reflectionless filter has high component precision and high Q value.In this paper,the reflectionless filter is studied and designed using the IPD technology of high-resistance silicon substrate.Firstly,according to the nature of the symmetric two-port network,the condition that the two-port network has reflectionless is derived,and then the circuit topology of the reflectionless filter is obtained according to the conditions.Then some methods to improve the performance of the reflectionless filter were studied,and the actual feasibility was verified by the HFSS simulation software.Then,the same method is used to derive several types of reflectionless filters with different topologies.The HFSS simulation reflectionless filter is also used to verify the correctness of the conclusion.Finally,according to the characteristics of the reflectionless filter absorbing the stop-band signal,the reflectionless filter is designed by using the complementary duplexer.Two reflectionless filters designed by the complementary duplexer are proposed,and some methods are used to improve the reflectionless filter.The performance of the filter was reflected,and this reflectionless filter was simulated using HFSS and the conclusions were verified.