A Compact Low Loss Single-Ended to Two-Way Differential Power Divider/Combiner

This letter presents the analysis and design of a novel compact single-ended to two-way differential passive power divider/combiner using coupled lines. A model for the power combiner/divider is proposed and verified using electromagnetic simulations and measurements. The coupled line power combiner (CLPC) is designed at 5 GHz center frequency and fabricated on a standard 4-layer FR-4 printed circuit board. The combiner core has dimensions of 4.1 × 8.5 mm
²
. Measurement results show an input matching below -10 dB from 3 to 6 GHz, and an insertion loss less than 0.5 dB over the same frequency range. The amplitude mismatch between the output ports is less than 0.5 dB, and the phase mismatch is less than five degrees.