Analysis And Design Of Phase - Shift Delay Circuit

Phase shifter and delay line are important microwave control circuits. By controlling the phase form 0 to 360 degree, phase shifter can control the transmission direction of microwave beam, while delay line control microwave by changing the integral wavelength. Nowadays, phase shifter and delay line are widely used in many fields such as radar system, microwave communication, electromagnetic countermeasure (ECM), satellite technology, etc. With the upgrading of microwave technology, the researches of microwave controlling circuits are aimed at the performances of broadband, high power, miniaturization and integration. The main contents of this thesis are listed below:Firstly, an L band 4-bit digital phase shifter is designed to realize broadband and high power. Method for the selection of PIN diode for high power capacity is discussed. And then, parallel γ/8 open and short stubs and A/4 impedance transformer are used to improve switched-line phase shifter for realizing broadband. The measured results show that the return loss of the phase shifter is better than 15.5 dB covering 23.9% bandwidth, which match well with simulation.Secondly, the LTCC technology and SIW transmission line are used to design an X band delay line. Because of fully utilizing the advantages of LTCC, serious mismatching problem needs to be addressed. Two topologies based on γ/4 impedance transformer are proposed. Return loss of the analyzed topology is better than 18 dB from 9.5 to 10.5 GHz. The simulated results indicate good performances which are realized in our design.