Design Of Ku-Band 6-Bit Digital Phase Shifter

Phase shifter is widely used in the automobile GPS and satellite system,especially in the phase array radar system and multi-beam antennas.It controls the direction of the beam by changing the signal phase,and is the key component of transmit/receive module in Phased array radar.Phased array radar has many T/R components.All these components need a corresponding digital phase shifter.How to reduce the cost and chip area without affecting the performance of the system makes the study of this project meaningful.First,this thesis introduces some switch circuits based on SiGe semiconductor technology.Then,the SPDT(single pole double throw)switch are introduced in details.The basic theory of digital phase shifter is presented in this paper.After a in-depth analysis of the phase shifter’s characteristics,this paper studies the the Ku band phase shifter realized in lumped elements.The proposed phase shifter is designed using High-pass filter type for 180° and 90° unit,using band-pass filter type for 45°、22.5°、11.25°、5.625° unit.A novel band-pass filter phase shifter unit is designed to decrease the amplitude fluctuation.In addition,the foundry can not provide small inductor due to process limitations,so the spiral inductor is designed for phase shifter.In order to make the simulation result more accurate,electromagnetic field simulation is applied in the design of the phase shifter.Finally,the Ku-band 6-bit phase shifter is implemented based on 0.13μm BiCMOS process.The overall size of the chip is 1.57mm ×1.3mm.RMS phase error is less than 3° and the insertion loss is less than 13dB,phase amplitude fluctuation is less than 0.8dB.