Design and analysis of three stage one into four-way equal Wilkinson Power Divider

Wilkinson power divider (WPD) is a widely adopted technique for splitting the microwave signal into two equal or unequal parts and maintaining good isolation between output ports. A lot of research has been carried out in exploring different variants of WPD. In order to increase the bandwidth, multi stage WPD is used. This work aims to design and analyze the performance of a three-stage 1-into-4 Wilkinson equal power divider suitable for frequency band 2-5 GHz. The design has been realized on S7136H 20-mil substrate. The design was optimized for 1 into 2 two stage WPD cell and three such basic cells have been utilized according to layout requirement. The symmetry of design is maintained to ensure minimum amplitude and phase variation among output ports. Overall size of the fabricated circuit is 44.7x75.8 mm. Physical results show insertion loss better than 1.0 dB at 2 GHz and better than 2.0 dB at 5 GHz. Return loss is better than 18 dB at both input and output ports. Isolation between adjacent output ports is better than 20 dB.