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Radio occultation observations of the solar corona over 1.60-1.86R⊙: Faraday rotation and frequency-shift analysis
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-02)
The study of coronal energy transport, central to the solar wind acceleration problem, relies upon accurate representation of magnetic fields and plasma electron densities. This information is difficult to obtain in middle‐to‐lower coronal regions that may contain complex magnetic structures. Faraday rotation (FR) solar radio occultation observations, which reveal line‐of‐sight (LOS) integrated ...
Bistatic Observations of the Ocean Surface with HF Radar, Satellite and Airborne Receivers
(Peer reviewed; Book; Bok; Bokkapittel; Chapter, 2017-12-25)
A new concept has been developed which can view vast regions of the Earth's surface. Ground HF transmissions are reflected by the ionosphere to illuminate the ocean over a few thousand kilometers. HF receivers detect the radio waves scattered by the sea and land surface. Using the theory of radio wave scatter from ocean surfaces, the HF data is then processed to yield the directional wave-height ...
Range-Doppler Mapping of Space-Based Targets Using the JRO 50 MHz Radar
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-12-02)
The Jicamarca Radio Observatory (JRO) two-dimensional square array radar system operating at ~ 6-m wavelength was used to study the Moon and low Earth orbit satellites using the Range-Doppler inverse synthetic aperture radar technique also known as Delay-Doppler imaging. The radar data was collected on Oct 21, 2015. A circularly polarized coded pulse was transmitted from a quarter-array antenna ...
Four dimensional quantification of Kelvin-Helmholtz instabilities in the polar summer mesosphere using volumetric radar imaging
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12-13)
We present and characterize in time and three spatial dimensions a Kelvin‐Helmholtz Instability (KHI) event from polar mesospheric summer echoes (PMSE) observed with the Middle Atmosphere Alomar Radar System. We use a newly developed radar imaging mode, which observed PMSE intensity and line of sight velocity with high temporal and angular resolution. The identified KHI event occurs in a narrow layer ...
The science case for the EISCAT_3D radar
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-29)
The EISCAT (European Incoherent SCATer) Scientific Association has provided versatile incoherent scatter (IS) radar
facilities on the mainland of northern Scandinavia (the EISCAT UHF and VHF radar systems) and on Svalbard (the
electronically scanning radar ESR (EISCAT Svalbard Radar) for studies of the high-latitude ionised upper atmosphere
(the ionosphere). The mainland radars were constructed ...
Investigation of exceptionally radar-dark regions on the lunar nearside
(Conference object; Konferansebidrag, 2019-08)
Remote sensing of planetary surfaces is an effective method for gaining knowledge of the processes that
shape the planetary bodies in our solar system. This is useful for uncovering the environment of the primordial solar system and to study the current state of the upper crusts of the other planets in our neighborhood. A recent 6-meter wavelength polarimetric radar map of the Moon [?] showed ...
First observations of the McMurdo-South Pole oblique ionospheric HF channel
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-09)
We present the first observations from a new low-cost oblique ionosonde located in Antarctica. The transmitter is located at McMurdo Station, Ross Island, and the receiver at Amundsen–Scott Station, South Pole. The system was demonstrated successfully in March 2019, with the experiment yielding over 30 000 ionospheric echoes over a 2-week period. These data indicate the presence of a stable E layer ...
Radar imaging with EISCAT 3D
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-04)
A new incoherent scatter radar called EISCAT 3D is being constructed in northern Scandinavia. It will have the capability to produce volumetric images of ionospheric plasma parameters using aperture synthesis radar imaging. This study uses the current design of EISCAT 3D to explore the theoretical radar imaging performance when imaging electron density in the E region and compares numerical techniques ...
Sparse signal recovery in MIMO specular meteor radars with waveform diversity
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-15)
Since the 1950s, specular meteor radars (SMRs) have been used to study the mesosphere and lower thermosphere (MLT) dynamics. Atmospheric parameters derived from SMRs are highly dependent on the number of detected meteors and the accuracy of the meteors' locations. Recently, incoherent and coherent multiple-input-multiple-output (MIMO) radar approaches combined with waveform diversity have been ...
Planetary radar science case for EISCAT 3D
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-12)
Ground-based inverse synthetic aperture radar is
a tool that can provide insights into the early history and
formative processes of planetary bodies in the inner solar
system. This information is gathered by measuring the scattering matrix of the target body, providing composite information about the physical structure and chemical makeup
of its surface and subsurface down to the penetration ...