Summary

Description

<p>Metal patches were developed for the Juno Microwave radiometer instrument at P-band and L-band. The absence of dielectric in the metal patch design obviated issues with static discharge in the Jupiter orbital environment. However, metal patches readily scale to operation at other frequencies, and have excellent loss performance at W-band. Moreover, metal patches can be fabricated accurately using photo-lithographically defined microfabrication techniques that are dielectric free. The metal patch antenna elements that will be developed in this work are intended for use in an array-fed reflector system that is scanned in azimuth through the use of phase shifters in transmit and receive MMICs. This technology will support W-band cloud radar for the Aerosol/Cloud/Ecosystem (ACE) decadal survey mission, as well as other millimeter-wave applications. The focus of this work is to develop the antenna elements and associated feed networks; active electronics will be developed separately. The work will result in the design, fabrication, and testing of a 2x2 element array, termed a unit cell. A much larger feed array will be formed as the linear concatenation of these unit cells in subsequent development work. The unit cell (illustrated below) developed in this work incorporates all of the salient features that are critical to constructing larger scanning arrays, including the microfabricated feed network and the capability to predict scan performance. As a key part of the verification approach, a waveguide adapter fixture to measure network performance and element patterns of the unit cell device.</p>