A spaceborne radar system that operates simultaneously at multiple frequency bands from microwave through millimeter-wave frequencies can exploit the largely varying frequency response of electromagnetic radiation to various atmospheric conditions, thus forming a highly-capable remote sensing system for NASA earth science objectives such as cloud and precipitation monitoring. We propose the development of an electrically scanned, co-located Ku/Ka-band (13.4/35.6 GHz) linear array in the Nuvotronics PolyStrata® technology for integration with an electrically scanned W-band (94 GHz) linear array to form the feed for a three-band remote sensing system. The PolyStrata® wafer-scale microfabrication process, with the capability to monolithically integrate dielectric-free antenna arrays with ultra-low-loss air-coax feed networks in three-dimensions, will be a key enabler of achieving the state-of-the art performance requirements for front-end losses at the desired operating frequencies as well as the desired scalability to 2-3 meters. Unprecedented transmit efficiencies and power levels will be achieved by leveraging Nuvotronics' history of developing Gallium Nitride (GaN) power amplifiers and low-loss switches at similar frequencies. A prototype hardware demonstration of the co-located Ku/Ka-band antenna array fabricated in the PolyStrata® process will be provided.