Off-chip Wideband Power Divider/Combiner for Sub-THz Receiver Module

A modified model of Wilkinson power divider/combiner with a bandwidth of 40 GHz is developed through this work. The divider is designed off-chip on low transmission loss PCB for implementing sub-THz receiver module at 275 GHz. For broad bandwidth functionality, the isolation element section is shifted down along the quarter-wavelength elements to a shorter length θ below 90°. A radial stub is then introduced at the new shifted isolation section to compensate for this shift. The divider is designed in HFSS and the results have shown a fractional bandwidth of 90% with center frequency around 50 GHz at a reflection loss level of 15 dB. The maximum insertion loss is 3.33 dB while both isolation and reflection levels at output ports are better than −10 dB over the whole band of interest. The new wideband power divider (WBPD) is proposed to enable the robust platform for multiple CMOS receiver chips on-board integration with beamforming capability. Different PCB design considerations are described in details.