A Coherent Method for Simulating Active and Passive Radar Sounding of the Jovian Icy Moons

et al. 2022

Preprint

Section: Stratton-chu Formula With a Time-domain Signalmentioning

confidence: 99%

The phase response of a rough rectangular facet for radar sounder simulations of both coherent and incoherent scattering

Gerekos

Haynes

et al. 2022

Preprint

“…The timing problem for acquiring the incoming noise has been previously discussed in [48], where the recorded incoming signal is cross-correlated with its backscattered fields. Here, we focus on the backprojection phase for an active and passive radar, as well as for off-nadir passive radar acquisitions.…”

Section: E Sar Focusing With Time-domain Backprojectionmentioning

confidence: 99%

Passive Synthetic Aperture Radar Imaging Using Radio-Astronomical Sources

Peters

IEEE Trans. Geosci. Remote Sensing

Haynes

et al. 2021

Recent work has demonstrated a passive radio sounding approach that uses the Sun as a source for echo detection and ranging. As the Sun is a moving source with a position that is known a priori, we evaluate this technique's capabilities to measure the echo's phase history, map topography, and perform synthetic aperture radar (SAR) focusing. Here, we present our approach to implementing passive SAR using a compact, temporally incoherent radio-astronomical source as a signal of opportunity. We first evaluate the passive system's capabilities to obtain an echo from a rough surface by determining the critical signal-to-noise ratio (SNR) for reliably observing the Sun's echo reflection with our passive instrument. We then demonstrate that our technique can detect the necessary changes in range, phase, and reflectivity of an echo from the Sun. We next present the experimental results of our passive radar testing using the Sun at Dante's View, Death Valley, to highlight this technique's ability to perform 2-D imaging. Finally, with synthetic data, we demonstrate that we can use time-domain backprojection to focus a planar white noise signal, perform passive SAR imaging, and improve the measurement's SNR and azimuth resolution. The results of passive SAR focusing on white noise highlight the potential for the Sun and Jupiter's radio emissions to perform surface and subsurface imaging for planetary and terrestrial observations.

“…Let us consider only one harmonic distortion. In this case, the distorted autocorrelation function is equal to: From (18), the autocorrelation distorted outputR s (t), is equal to the output of an ideal autocorrelation function R s (t) which is then replicated and centered at time instants equal to the harmonic number c n and amplitude scaled for the harmonic coefficient a n . Depending on the values of a n and c n , the nuisance term K(f ) may degrade resolution (small values of c n ) or increase the overall noise floor level (high values of c n ).…”

Section: B Impact Of Waveforms Non Idealities On Subsurface Detection Capabilitiesmentioning

confidence: 99%

“…Thus, recently a passive low frequency (about 1 MHz) instrument has been proposed [17]. Recently, Gerekos et al [18] presented a method for simulating and comparing both passive and active acquisitions of jovian icy moons.…”

Section: Introductionmentioning

confidence: 99%

Analysis of Temporal and Structural Characteristics of Jovian Radio Emissions for Passive Radar Sounding of Jupiter’s Icy Moons

Carrer

IEEE Trans. Geosci. Remote Sensing

Romero-Wolf

et al. 2021

Self Cite

Recent studies have proposed that Jovian Decametric Radiation (DAM) can be effectively exploited for probing the subsurface of Jupiter's icy moons by using passive radio sounding. However, these studies were based on the assumption that Jovian noise is white and stationary. Therefore, additional investigations into the temporal stability, predictability, and spectral properties of Jovian noise are required to fully assess the potential of passive radar sounding and improve the acquisitions planning. In this paper, we investigate these properties of the Jovian DAM to understand their impact on radar sounding performance. This is done by analyzing the recently available radio spectra acquired by the JUNO Waves instrument. Results are also evaluated for the specific case of the Radar for Icy Moon Exploration (RIME) and the Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON) that have been selected for ESA and NASA missions to Ganymede and Europa. Our results show that the Jovian DAM is not perfectly white but no severe distortions in the range response should be expected. The results on spatio-temporal occurrence show that Jupiter's DAM has a variable probability of occurrence, which is rather sporadic for some frequency ranges. The results on RIME and REASON flybys show that the Jovian DAM occurrence probability is relatively low for selected sub-jovian flybys at Europa. For the RIME Ganymede orbital phase a large number of high occurrence passive acquisition opportunities are expected. The experimental results also show that a large bandwidth receiver would enhance the chance of recording Jovian noise.