Packaged In-Phase/Out-of-Phase Printed Multi-Layer Power Dividers

Microstrip line (MSL) multi-layer structures have been widely used to miniaturize circuits, possibly by half at the cost of narrower bandwidth and high leakage at mm Wave frequency bands. Moreover, phase matching becomes challenging, as the phase linearity differs through different layers. Here, a novel design is presented for MSL multi-layer power dividers with equal power division but different phase outputs. The power is transferred from one layer to another through an elliptic slot on a thick conducting plate. Various slot and matching transformers shapes control the phase difference between the output ports and the input matching bandwidth. To suppress radiation losses and leakage, the structure is packaged by artificial magnetic conductors from the top and bottom. The realized power dividers achieve a phase difference from 0° to
$180^{\circ}\pm 6^{\circ}$
with a matching input level below -15 dB within 21.8% bandwidth at center frequency 29.75 GHz.