A 4 Meter 180 to 680 GHz Antenna for the Scanning Microwave Limb Sounder
No abstract available
Cofield, Richard↗
Engineering topics
Stek, Paul
Publications and source records attributed to Stek, Paul.
A Deployable 4 Meter 180 to 680 GHz Antenna for the Scanning Microwave Limb Sounder
No abstract available
Global Atmospheric Composition Mission (GACM)↗
Sideband-Separating, Millimeter-Wave Heterodyne Receiver
Researchers have demonstrated a submillimeter-wave spectrometer that combines extremely broad bandwidth with extremely high sensitivity and spectral resolution to enable future spacecraft to measure the composition of the Earth s troposphere in three dimensions many times per day at spatial resolutions as high as a few kilometers. Microwave limb sounding is a proven remote-sensing technique that measures thermal emission spectra from molecular gases along limb views of the Earth s atmosphere against a cold space background.
Ward, John S.↗
Digital Spectrometers for Interplanetary Science Missions
A fully digital polyphase spectrometer recently developed by the University of California Berkeley Wireless Research Center in conjunction with the Jet Propulsion Laboratory provides a low mass, power, and cost implementation of a spectrum channelizer for submillimeter spectrometers for future missions to the Inner and Outer Solar System. The digital polyphase filter bank spectrometer (PFB) offers broad bandwidth with high spectral resolution, minimal channel-to-channel overlap, and high out-of-band rejection.
polyphase filter bank spectrometer (PFB)↗
LEOMAC: A Future 'Global Atmospheric Composition Mission' (CACM) Concept
Resolution of important outstanding questions in air quality, climate change and ozone layer stability demands global observations of multiple chemical species with high horizontal and vertical resolution from the boundary layer to the stratopause. We present a mission concept that delivers the needed atmospheric composition observations, along with cloud ice and water vapor data needed for improvements in climate and weather forecasting models. The mission comprises ultraviolet and infrared nadir and microwave limb viewing instruments observing wide swaths each orbit. We review the scientific goals of the mission and the measurement capabilities this concept will deliver. We describe how precessing orbits offer significant improvements in temporal resolution and diurnal coverage compared to sun-synchronous orbits. Such improvements are needed to quantify the impact of critical 'fast processes' such as deep convection on the composition and radiative properties of the upper troposphere, a region where water vapor and ozone are strong but poorly understood greenhouse gases. This concept can serve as the 'Global Atmospheric Composition Mission' (GACM) recently recommended by the National Academy of Sciences decadal survey as one of 17 priority earth science missions for the coming decade.
chemistry↗