INTEGRATED MICRO-COAXIAL PASSIVE COMPONENTSFOR MILLIMETER-WAVE ANTENNA FRONT ENDS

摘要

Miniature 250 to 700-μm tall copper air-filled rectangularcoaxial line with inner conductor supported by periodicdielectric straps is demonstrated. The measured loss is aslow as 0.08dB/cm at 37GHz, while the isolation betweentwo parallel lines with center-to-center separation of350pm is better than 60dB. A number of quasi-planarcomponents are designed to be fabricated on the same 6-inch wafer using a sequential micro-fabrication processwith 5 to 10 layers of copper. This paper presents anoverview of several components that have beendemonstrated in the air-micro-coax technology: low-lossdensely-packed lines with a range of characteristicimpedances; patch-type antenna elements; branch-linehybrids; cavity resonators; a Buttler matrix beamformingnetwork. In addition to these components, the paper alsodiscusses dividers/combiners and broadband hybrids, withan overview of the limitations and advantages of thetechnology.