Dual-band Chireix combining network

Abstract

This work presents a novel arbitrary dual-band Chireix power combining network, for which bandpass filter theory is extended to achieve dual-band performance. The two frequencies (4.4 GHz and 5.2 GHz) at which the Chireix outphasing combiner is tuned are designed by selecting the two cutoff frequencies of a bandpass filter. The filter is implemented using a modified stepped impedance structure. Synthesis, design methodology and implementation of the proposed network is presented in this paper. Measurement results of the microstrip power combining network show good agreement with the simulated results, verifying the theory and the proposed design methodology.