Planar wideband inphase power divider/combiner using modified Gysel structure

The design of a wideband inphase power divider/combiner is presented. It uses a modified Gysel structure for an increased band and a reduced number of isolation resistors to only one. The power divider has a simple structure that does not use any slots in the ground plane, and is thus fully compatible with microstrip circuits. Moreover, the device uses one external isolation resistor, and thus it is suitable for high-power microwave applications because of the easy connection of the isolation resistor to a suitable heat sink. A theoretical analysis is presented to find the values of the design parameters for wideband performance. The simulated and experimental results of the designed divider show 69% fractional bandwidth assuming 15 dB of isolation as a reference.