Title: The Compact Adaptable Microwave Limb Sounder (CAMLS)
Presenting Author: Nathaniel J Livesey
Organization: Jet Propulsion Laboratory

Abstract:
The goal of the Compact Adaptable Microwave Limb Sounder (CAMLS) Instrument Incubator Program (IIP) project is to develop an engineering model integrating the key enabling system and subsystem technologies for a next-generation Microwave Limb Sounder instrument for atmospheric composition. CAMLS builds on earlier IIP, ACT, SBIR, and JPL internal efforts, with heritage from the Microwave Limb Sounder (MLS) instruments on NASA's UARS and Aura missions. We will develop the core receiver/spectrometer system for a 340-GHz instrument making unique and essential observations of composition, humidity, temperature and clouds in Earth's upper troposphere (UT, the atmospheric region from ~10-15km) and stratosphere (from the UT to ~50km). Specific tasks for this 3-year effort include: 1. Developing a compact Monolithic Microwave Integrated Circuit, Low Noise Amplifier-based receiver front end (RFE) at 340GHz. Aura MLS had seven receivers in five frequency bands. A single RFE at 340GHz can make the most important UT and stratospheric measurements using an antenna only 70% the height of that needed for the MLS 190-GHz UT observations, giving an instrument that is far easier to deploy on a mission of opportunity. 2. Developing a compact, low-power, low-mass digital spectrometer back end, taking advantage of rapid technology developments driven by the communication industry, to further simplify and miniaturize subsystems developed through previous ESTO and SBIR-funded efforts. 3. Integrating the receiver and spectrometers into an engineering model system and demonstrating performance over RFE temperature to inform performance, complexity, and cost trades. 4. Integrating the system, plus cost-effective coolers, into the existing Airborne-SMLS instrument, demonstrating capability in a relevant environment, establishing TRL-6. The end product will be a compact, low-mass, low-power, low-cost mature instrument that can be implemented confidently within the budgetary and schedule constraints of the Earth Venture program. Additionally, with appropriate cooling, it could serve as the basis of a Decadal Survey class mission providing cross-track scanning for detailed transport and trace gas studies. In addition to describing each of the main aspects of the CAMLS IIP project, this paper will review the scientific issues CAMLS seeks to address, and describe the measurements expected from CAMLS.