ADVANCEMENT IN SPACEBORNE MICROWAVE-PHOTONIC TECHNOLOGY AT NASA GODDARD SPACE FLIGHT CENTER

F. Gambini^1,2,3, A. Gambacorta², M. Fritts², B. Bulcha², V. Torres², P. Mohammed^4,2, S. Nicholls^5,2, E. Leong², M. Coon², R. Banting^6,2, J. Piepmeier², M. Stephen², J. Lucey²

¹University of Maryland Baltimore County, ²NASA Goddard Space Flight Center, ³CRESST II, ⁴Morgan State University, ⁵Science Systems and Applications INC, ⁶ASRC Federeal System Solutions

This presentation introduces the latest technological advancements in hyperspectral microwave instruments developed at NASA Goddard Space Flight Center (GSFC).

Over the past fifty years, microwave spaceborne sensors have been providing critical information on the Earth’s surface and atmospheric parameters, including temperature, water vapor, and hydrometeors. However, traditional microwave technology limits the instrument performance due to size, weight, power consumption, and cost (SWaP-C) constraints.

Photonic technology offers a transformative and versatile solution, providing access to an unprecedented bandwidth, while photonic integrated circuits (PIC) minimize the system SWaP-C without compromising the noise level of the observations. The combination of PIC technology with application-specific integrated circuits (ASIC) further enhances the sounding performance by enabling hyperspectral sounding capabilities with thousands of spectral channels.

First, we will present the latest developments from the Hyperspectral Microwave-Photonics Instrument (HyMPI) project. HyMPI represents the first successful demonstration of PIC applied to hyperspectral microwave sensing. We will present key aspects of the microwave subsystem and photonic components, particularly the photonic integrated channelizer, which is based on a NASA Goddard patented design named Serial Arrayed Waveguide Grating (SAWG). The SAWG is the core of HyMPI’s architecture and is based on an innovative design that enables unprecedented bandwidth coverage while limiting inter-channel crosstalk and maintaining minimum SWaP-C.

HyMPI recently concluded a rooftop campaign that marked its first demonstration of Earth’s atmospheric sounding at superspectral (4 GHz) and hyperspectral (3.9 MHz) resolution. We will show the results related to the noise performance of both the superspectral and hyperspectral channels and provide comprehensive findings from the rooftop campaign.

HyMPI pioneers the development of the first space-based hyperspectral microwave sensor: the Advanced Ultra-high Resolution Optical and RAdiofrequency (AURORA) Pathfinder. AURORA Pathfinder’s mission aims to demonstrate PIC and ASIC digital spectrometers in space, along with on-board calibration of hyper- and super-spectral microwave payloads.

This overview concludes with the most recent technological advances of AURORA Pathfinder, focusing on the photonic instrument that targets the 125 – 175 GHz Planetary Boundary Layer (PBL) window region with previously unattainable resolution. AURORA’s photonic instrument requirements will be presented together with the performance of a new generation of the photonic integrated SAWG, which minimizes the channel correlation and provides high channel frequency stability. Data from this instrument are expected to enable groundbreaking scientific discoveries.