A Compact Dual-Frequency Three-Way Unequal Power Divider

Abstract

In this paper, a compact dual-frequency three-way unequal power divider is presented. The design of the proposed power divider is accomplished by transforming the length and impedance of each quarter-wave branch into two sections with the characteristic impedance of Z 1 and Z 2, the length of λ/4 and four resistors which provide enough isolation at two frequencies. The configuration of the proposed power divider and formulas used to determine the design parameters are given. To verify the validity of the formulas, a three-way power divider with a power split ratio of 1 : 1.5 : 3 for two frequencies of 915 MHz and 2450 MHz is fabricated and measured. The size of the proposed power divider is about two thirds of that of the conventional one. The measured results show good agreement with the simulated ones. Good experimental performances of the proposed power divider, including an unequal power split, low return loss, and good isolation at the two frequencies between the output ports, are obtained.