The Integrated Design of Power Dividerand Low-pass Filter

Abstract

Abstract A compact filtering Wilkinson power divider with harmonic suppression based on lumped components is presented in this paper. The new divider uses two 5th-order elliptic-function low-pass filters to replace the quarter wavelength microstrip lines of the conventional Wilkinson power divider. The structure combines the power divider and the filter into a complete device. By integrating elliptic low-pass filters with the power divider, the proposed structure can suppress harmonics due to the filter’s band-notched characteristic. The power divider demonstrates a measured suppression of 37.1 dB for the second harmonic, 36.6 dB for the third harmonic, 38.6 dB for the fourth harmonic respectively. The harmonic suppression is higher than 20 dB from 2.75 to 7.035 GHz. Furthermore, lumped components are utilized to achieve improvement on size reduction. Compared with the conventional divider, the proposed structure effectively reduces the size by 77 %. The insertion loss is 3.2 dB at the center frequency (1.45GHz).