Correlating Radiometers

This proposal is responsive to NASA SBIR Subtopic S1.03: Technologies for Passive Microwave Remote Sensing; specifically, the item titled ldquo;Correlating radiometer front-ends and low 1/f-noise detectors for 100 ndash; 700 GHz.rdquo; The focus is on low DC power radiometers for SmallSats and CubeSats and the use of the correlating receiver architecture to achieve useful system stability without the requirement for Dicke switching or noise-injection.nbsp; These will be LNA based radiometers and the correlating technology will be used to attenuate the impact of gain instabilities in the amplifiers. Compact size and power efficiency are critical for the SmallSat form factor and VDIrsquo;s innovative receiver integration technology is critical for the success of this effort. As is the use of VDIrsquo;s technology for achieving optimal packaging of amplifiers, using microfabricated waveguide probes, in the frequency band of interest. The Phase I research includes the demonstration of two prototype correlating receivers: one using direct detection (LNA ndash; RF Detector) and the other using a heterodyne receiver (LNA ndash; Mixer ndash; IF Detector). Also included is an investigation of 1/f noise in direct detectors in the 100 ndash; 700 GHz range. The deliverables include the two correlating receiver systems.