A Modified Microstrip Wilkinson Power Divider with High Order Harmonics Suppression

In this paper, a modified Wilkinson power divider structure with three order harmonics suppression is presented. The quarter-wavelength microstrip lines in the traditional Wilkinson power divider (WPD) are replaced by two transmission line segments with ends connected (TTLWEC). The TTLWEC performs the functions of impedance transformation and three order harmonics suppression. The design equations are deduced by odd- and even-mode theory. An example of power divider operating at 1 GHz is designed and fabricated based on the printed circuit board technology. The measured results of 3.13 dB insert loss (IL) and 35 dB return loss (RL) are obtained at the operating frequency, and the first, second and third harmonic harmonics suppressions are -38 dB, -44 dB and -39 dB, respectively, which agree well with the simulated results and validate the availability of the proposed structure.