A 170 GHz 45 degree Hybrid for Submillimeter Wave Sideband Separating Subharmonic Mixers

Artikel i vetenskaplig tidskrift, 2008

We present a 135/45 degree phase shifter hybrid intended to be used in subharmonic sideband separation mixer schemes at submillimeter-wave frequencies. The design consists of an increased height 90 degree 6-arm branch guide coupler with a three stub loaded differential line 45 degree phase shifter at the output. The device has been implemented at G-band in an E-plane WR-05 splitblock design with a center frequency of 170 GHz and 15% bandwidth. Measured S-parameter are in good agreement with simulations showing an isolation and return loss better than 20 dB and an amplitude and phase imbalance within 0.4 dB and 2 degree, respectively.