60 GHz ultrawideband front-ends with gain control, phase shifter, and wave guide transition in LTCC technology
For high-data-rate multimedia access and measurement applications (such as channel sounding and radar) the 60 GHz unlicensed band is of interest for short range applications. Currently, there is enormous progress in the field of monolithic-millimeter-wave-integrated-circuits (MMIC) for 60 GHz technology, but there are still many challenges related to reliability and usable bandwidth for compact packaging solutions. The aim of this work is to demonstrate the implementation of miniaturized 60 GHz front-ends, including fully differential MMICs, with gain control and phase-shifting capabilities, interconnected to a broadband differentially fed waveguide for the WR-15 standard. The front-ends were designed based on MMICs using 0.25 μm SiGe BiCMOS and packaging on low-temperature-cofired-ceramics (LTCC) technology. We have designed, simulated, fabricated, and tested the front-ends showing a useable bandwidth of more than 12 GHz at the 60 GHz band fulfilling the requirements of the IEEE 802.11ad standard.