Martin Perrine

Development of the NASA High-Altitude Imaging Wind and Rain Airborne Profiler

The scope of this paper1 is the development and recent field deployments of the High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP), which was funded under the NASA Instrument Incubator Program (IIP) [1]. HIWRAP is a dual-frequency (Ka- and Ku-band), dual-beam (30° and 40° incidence angles), conical scanning, Doppler radar system designed for operation on the NASA high-altitude (65,000 ft) Global Hawk Unmanned Aerial System (UAS). It utilizes solid state transmitters along with a novel pulse compression scheme that results in a system with compact size, light weight, less power consumption, and low cost compared to radars currently in use for precipitation and Doppler wind measurements. By combining measurements at Ku- and Ka-band, HIWRAP is able to image winds through measuring volume backscattering from clouds and precipitation. In addition, HIWRAP is also capable of measuring surface winds in an approach similar to SeaWinds on QuikScat. To this end, HIWRAP hardware and software development has been completed. It was installed on the NASA WB57 for instrument test flights in March, 2010 and then deployed on the NASA Global Hawk for supporting the Genesis and Rapid Intensification Processes (GRIP) field campaign in August-September, 2010. This paper describes the scientific motivations of the development of HIWRAP as well as system hardware, aircraft integration and flight missions. Preliminary data from GRIP science flights is also presented.

The ecosystems SAR (EcoSAR) an airborne P-band polarimetric InSAR for the measurement of vegetation structure, biomass and permafrost

EcoSAR is a new synthetic aperture radar (SAR) instrument being developed at the NASA/ Goddard Space Flight Center (GSFC) for the polarimetric and interferometric measurements of ecosystem structure and biomass. The instrument uses a phased-array beamforming architecture and supports full polarimetric measurements and single pass interferometry. This Instrument development is part of NASAs Earth Science Technology Office Instrument Incubator Program (ESTO IIP).

The NASA High-Altitude Imaging Wind and Rain Airborne Profiler

The High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) is a dual-frequency (Ka- and Ku-bands), dual-beam (30° and 40° incidence angles), and conical scanning Doppler radar designed for operation on the NASA high-altitude (~19 km) Global Hawk Unmanned Aerial System. HIWRAP was developed under the support of the NASA Instrument Incubator Program for studies of tropical storms and severe weather events. It utilizes solid-state transmitters along with a novel transmit and receive waveform scheme that results in a system with compact size, light weight, less power consumption, and lower cost compared to radars currently in use for precipitation and Doppler wind measurements. By combining volume backscattering measurements at Ku- and Ka-bands, HIWRAP is capable of imaging radar reflectivity and 3-D wind fields in clouds and precipitation. In addition, HIWRAP is also capable of measuring surface winds in an approach similar to SeaWinds on QuikSCAT. HIWRAP operating frequencies are similar to those used by the NASA Global Precipitation Measurement (GPM) Dual-frequency Precipitation Radar, making it suitable for providing airborne validation data for the GPM mission. This paper describes the scientific motivation for the development of HIWRAP as well as the system hardware, aircraft integration, and recent flight activities. Data from recent science flights are also presented.

ECOSAR: P-band digital beamforming polarimetric and single pass interferometric SAR

EcoSAR is a state-of-the-art beamforming synthetic aperture radar (SAR) recently developed at the NASA/ Goddard Space Flight Center (GSFC) for the measurement of ecosystem structure and biomass. The airborne instrument operates at a center frequency of 435 MHz (P-band), and uses a multi-channel reconfigurable architecture to implement fully polarimetric and “single pass” interferometric measurements. The instrument architecture allows for the real-time configuration radar parameters, including center frequency, resolution, incidence angle, and number of beams, among others. The system is also designed to operate in standard or ping pong interferometric modes, and in full, orthogonal, or hybrid polarimteric modes. The instrument development was recently completed, and its first flight campaign successfully conducted in March 2014 over areas of Bahamas and Costa Rica.

The EcoSAR P-band Synthetic Aperture Radar

The EcoSAR instrument is a new concept in Synthetic Aperture Radar for the polarimetric and interferometric measurements of biomass and ecosystem structure. EcoSAR will employ a digital beamforming architecture, a highly capable digital wave-form generator and receiver system, and advanced dual-polarization array antennas with an interferometric baseline of 25 m on the NASA P3 aircraft.

Digital Beamforming Synthetic Aperture Radar (DBSAR) polarimetric operation during the Eco3D flight campaign

The Digital Beamforming Synthetic Aperture Radar instrument demonstrated its first polarimetric polarization operation during the Eco-3D flight campaign, on board the NASA P3 aircraft in the summer/fall 2011. The measurements acquired during the campaign are currently being used to demonstrate DBSARs science utility by providing critical information on vegetation structure needed to estimate vegetation biomass in order to advance our understanding of the carbon cycle.

Development of the EcoSAR P-band synthetic aperture radar

This paper describes objectives and recent progress on the development of the EcoSAR, a new P-band airborne radar instrument being developed at the NASA/ Goddard Space Flight Center (GSFC) for the polarimetric and interferometric measurements of ecosystem structure and biomass. These measurements support science requirements for the study of the carbon cycle and its relationship to climate change. The instrument is scheduled to be completed and flight tested in 2013.

Digital beamforming synthetic aperture radar developments at NASA/Goddard space flight center

Advanced Digital Beamforming (DBF) Synthetic Aperture Radar (SAR) technology is an area of research and development pursued at the NASA Goddard Space Flight Center (GSFC). Advanced SAR architectures enhances radar performance and opens a new set of capabilities in radar remote sensing. DBSAR-2 and EcoSAR are two state-of-the-art radar systems recently developed and tested. These new instruments employ multiple input-multiple output (MIMO) architectures characterized by multi-mode operation, software defined waveform generation, digital beamforming, and configurable radar parameters. The instruments have been developed to support several disciplines in Earth and Planetary sciences. This paper describes the radars advanced features and report on the latest SAR processing and calibration efforts.

Development of the RF electronics unit for NASA's ecological synthetic aperture radar

In its Carbon Cycle research efforts, prioritized by the National Science Foundation Decadal Survey and mandated by the US Congress, NASA is developing an airborne P-band Ecological Synthetic Aperture Radar called EcoSAR. By using polarimetric and interferometric techniques, and a digital beamforming phased-array architecture, EcoSAR will characterize biomass and ecological structure in three dimensions aboard a P-3 aircraft. One of the main components in the EcoSAR instrument development is the 32 channel RF Electronics Unit (REU). The multi-channel solid-state REU design provides amplification, conditioning, blanking, and several calibration schemes to meet EcoSARs science and engineering requirements. The design, assembly, and testing of the REU is well underway with 16 of 32 channels completed. The remaining channels are nearly finished. The REU once complete, will be calibrated and integrated with the rest of the system in preparation for EcoSARs first flight campaign.