Multi-octave Mmic Digital Phase Shifter And Design

Digital phase shifter,based on RF monolithic microwave integrated circuit(MMIC) technology,is the core component of the transmit/receive(T/R) in the modern phased array radar system.The performance of the phase shifter has a direct impact on phased array radar system.This article introduces the research about multi-band MMIC digital phase shifter.Based on the requirement of this research,we carefully analyze the high/low pass structure and the reflective structure from the circuit theory,the character of the topology,the requirement of the specification,and the requirement of the size.According the result above, we determine the best program for designing the 6～18 GHz multi-band digital phase shifter.In this article,we also briefly introduce the knowledge about modeling the components which are used in the MMIC circuit.The passive component and the active component,in the circuit,have many forms,so we should model the component in right way,which is usually called circuit model parameter extraction.In the design process,we establish the equivalent model for the components and the control devices(PHEMT) in the circuit by the application model theory.Through the model process above,we could guarantee the correctness of the design.At the beginning of the article,we briefly introduce the concepts of phase shifter,MMIC and the application background.And in the middle of the article,we carefully analyze various types phase shifters and get some results,after summing up the characters of the various phase shifters circuit topology and the basic principles,we finally determine the design program,for instance,using the high/low pass structure to design the 5.625°/11.25°/22.5°phase shifter,and using the reflective structure to design the 45°/90°/180°phase shifter.And then,in the research process,we simulate various schematic circuits by Agilent ADS software. Based on the ideal optimization results above,we layout the schematic circuit,and optimize layout circuit parameter.Finally,by selecting one of the programs,we produce and test the 5 bits multi-band MMIC digital phase shifter,working in the frequency range of 6～18GHz. The test data shows that the test results accord the design result.The test datas are as follows:in the working frequency,the error of 11.25°bit is less than 1.65°;the error of 22.5°bit is less than 2.4°;the error of 45°bit is less than 4.1°;the error of 90°bit is less than 9.2°;the error of 180°bit is less than 8°.The insertion loss is restriction in the range of 7.5dB～11.8dB,input and output VSWR is less than 2.5.The area of multi-band MMIC 5-bits digital phase shifter is 3.555mm×4.055mm×0.1mm.