DESIGN OF A WIDEBAND DIFFERENTIAL PHASE SHIFTER WITH THE APPLICATION OF GENETIC ALGORITHM

In this paper, a wideband difierential phase shifter has been analyzed and designed using Genetic Algorithm (GA). The difierential phase shifter consists of two flxed main lines of length ‚/2, and parallel open and short stubs of length ‚/8, which are shunted at the edge points of the main lines, respectively. With the application of GA, an impedance match and minimum phase deviation for the desired phase shift over a wide frequency band are obtained. In order to verify the optimum results, simulation experiments are made and a 45 - phase shifter is fabricated and measured. The phase shifter exhibits an impedance bandwidth (jS11j < i10dB) and a consistent 45 - (§2 - ) phase difierence bandwidth around 66%.