Acquisition of a High Frequency Radar and Radio Imaging Array for Research in Space Plasma Turbulence, the Ionosphere, the Atmosphere, and Radio Technology
Abstract
We propose the acquisition of a 1 to 25-MHz radio system for use in ionospheric and atmospheric research. This project will leverage existing equipment to create a novel, unique, cutting-edge, medium and high-frequency (MF and HF) radar and radio imaging array in Puerto Rico. Radio equipment requested in this proposal, along with radio receiver and antenna systems already owned by the university, will be installed in an existing equipment shelter (a 24Õ by 36Õ doublewide trailer) and connected via cables to the antennas in the radio array. The radio array will consist of 64 radio crossed active electric dipole antennas connected to receiving systems. Key capabilities of the proposed array will be full polarization, high time resolution, wide frequency band, flexibility of operation, and phase coherence. Principle features of the array will be interferometric radar and radio direction-finding and, especially, radar and radio imaging of the ionosphere near the radio reflection altitude, using aperture synthesis and propagation-path optimization methods, which will be a completely new and novel technical and research capability. The Arecibo Observatory high-power high-frequency (HF) ionospheric research transmitter suffered significant damage during the collapse of the 900-ton instrument platform in December 2020. However, the HF transmitters were undamaged, and most of the required antenna system survived the collapse (specifically: the transmission cables, 70% of the 300-meter-diameter dish, the halfwave dipole transmitting elements, and the perimeter towers for suspending the secondary reflector). Current plans are to restore the Arecibo HF transmitting capability by the end of 2022. The HF facility is used to drive ionospheric plasma turbulence, producing sideband radio emissions which can be imaged by the proposed equipment. Radio imaging of the emissions with respect to the geomagnetic field, and with full polarization, will lead to important breakthroughs in our understanding of ionospheric plasma turbulence and space weather. Stimulated ionospheric turbulence is directly related to natural turbulence, which is part of the microphysics of space weather. Radar imaging by the proposed equipment will also have wide application in space weather research. The array will operate in a bistaic radar mode using the transmitter of the NOAA HF radar located at the USGS San Juan Observatory in eastern Puerto Rico. Bistatic radar imaging will provide a 3-D view (in latitude, longitude, and altitude) of ionospheric structure. Radar imaging observations will complement airglow imaging being done at Arecibo Observatory both in Arecibo and on the island of Culebra east of Puerto Rico, and will add to our knowledge of space weather connections between the equator and mid-latitudes. We have contacted collaborators who are interesting in supporting our proposed project through the co-location of additional instruments at the proposed array, including an optical imager, broadband VLF receivers, GNSS scintillation and total electron content receivers, geostationary VHF receivers, a VHF interferometer, a magnetometer, and lightning detectors (mapping arrays, interferometers, fast and slow antennas, and field mills). High-resolution observations of lightning radio emissions may be done using the proposed array, and observations of radio emissions and radar scatter from meteors may be done in collaboration with Arecibo Observatory lidar systems. The Bayam—n campus of Interamerican University of Puerto Rico is a private, primarily undergraduate institution with 99% Hispanic, mostly low-income students. The proposed equipment would enhance existing infrastructure at Interamerican University and in Puerto Rico, and would support STEM high school and undergraduate education and the development of graduate research programs. Areas of technological application include development of new remote sensing and commun
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 02, 2022
- Source ID
- W911NF2210144
Entities
People
- Brett Isham
Organizations
- Army Contracting Command
- Interamerican University of Puerto Rico
- Office of the Secretary of Defense