Effect of sea roughness on bistatically scattered range coded signals from the Global Positioning System

Garrison, James L.; Katzberg, Stephen J.; Hill, Michael

doi:10.1029/98gl51615

Cited by 207 publications

(127 citation statements)

References 3 publications

(1 reference statement)

Supporting

Mentioning

126

Contrasting

Order By: Relevance

“…Furthermore, these systems have predominantly been monostatic, measuring the power of the backscattered radiation. The possibility of using the radio navigation signals from the global positioning system (GPS) as a source of illumination in a forward-scattered radar remote sensing instrument for sea surface roughness was first presented, along with preliminary experimental measurement, in [1]. This measurement technique is unique, not only in the use of a bistatic geometry with existing sources of radio frequency illumination, but also in the use of the correlation properties of the pseudo-random noise (PRN) signal transmitted by GPS as opposed to requiring a direct measurement of received power.…”

mentioning

confidence: 99%

“…The technique in [1] measures the shape of the cross-correlation between a reflected signal and the locally generated PRN code. This paper documents the subsequent research performed to mechanize this instrument concept, involving the construction of a specialized GPS receiver and the inversion of bistatic scattering models to estimate wind speed from correlation measurements.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Wind speed measurement using forward scattered GPS signals

Garrison

Komjáthy

Zavorotny

et al. 2002

IEEE Trans. Geosci. Remote Sensing

293

137

View full text Add to dashboard Cite

Abstract-Instrumentation and retrieval algorithms are described which use the forward scattered range-coded signals from the global positioning system (GPS) radio navigation system for the measurement of sea surface roughness. This roughness has long been known to be dependent upon the surface wind speed. Experiments were conducted from aircraft along the TOPEX ground track and over experimental surface truth buoys. These flights used a receiver capable of recording the cross-correlation power in the reflected signal. The shape of this power distribution was then compared against analytical models, which employ a geometric optics approach. Two techniques for matching these functions were studied. The first recognized the most significant information content in the reflected signal is contained in the trailing edge slope of the waveform. The second attempted to match the complete shape of the waveform by approximating it as a series expansion and obtaining the nonlinear least squares estimate. Discussion is also presented on anomalies in the receiver operation and their identification and correction.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Wind speed measurement using forward scattered GPS signals

Garrison

Komjáthy

Zavorotny

et al. 2002

IEEE Trans. Geosci. Remote Sensing

293

137

View full text Add to dashboard Cite

show abstract

“…Later, the same principle was demonstrated as a useful tool to sense ocean roughness [6]. Exploiting a bistatic geometry approach, the GNSS satellites act as transmitters while an aircraft or a low Earth orbit satellite is the receiving platform.…”

Section: Introductionmentioning

confidence: 99%

Detection of buried objects using reflected GNSS signals

Notarpietro

Mattia

Campanella

et al. 2014

EURASIP J. Adv. Signal Process.

View full text Add to dashboard Cite

The use of reflected Global Navigation Satellite System (GNSS) signals for sensing the Earth has been growing rapidly in recent years. This technique is founded on the basic principle of detecting GNSS signals after they have been reflected off the Earth's surface and using them to determine the properties of the reflecting surface remotely. This is the so-called GNSS reflectometry (GNSS-R) technique. In this paper, a new application regarding the detection of metallic buried objects is analyzed and it is validated through several experimental campaigns. Although the penetration depth of GNSS signals into the ground is not optimal and depends on the soil moisture, GNSS signals can likely interact approximately with the first 10 cm of the ground and therefore can be reflected back by any metallic object buried on the first terrain layer. A very light and low-cost GNSS receiver prototype based on a software-defined radio approach was developed. This receiver can be used as a payload on board small drones or unmanned aerial systems to detect metallic objects (mines or other explosive devices). A signal processing tool based on an open-loop GNSS signal acquisition strategy was developed. The results of two experiments which show the possibility of using GNSS-R signals to detect buried metallic objects and to provide an estimate of their dimensions are discussed.

show abstract

“…Scientific applications of GNSS-R for Earth Observation include mesoscale ocean altimetry [1], wind speed measurements [2], ice altimetry [3], and soil moisture and vegetation determination [4]. There are different data acquisition techniques [5]: Conventional GNSS-R (cGNSS-R) [6], interferometric GNSS-R (iGNSS-R) [7], and reconstructed-code GNSS-R (rGNSS-R) [8].…”

Section: Introductionmentioning

confidence: 99%

First Polarimetric GNSS-R Measurements from a Stratospheric Flight over Boreal Forests

et al. 2015

View full text Add to dashboard Cite

Abstract:The first-ever dual-frequency multi-constellation Global Navigation Satellite Systems Reflectometry (GNSS-R) polarimetric measurements over boreal forests and lakes from the stratosphere are presented. Data were collected during the Swedish National Space Board (SNSB)/European Space Agency (ESA) sponsored Balloon Experiments for University Students (BEXUS) 19 stratospheric balloon experiment using the P(Y) and C/A ReflectOmeter (PYCARO) instrument operated in closed-loop mode. Maps of the polarimetric ratio for L1 and L2 Global Positioning System (GPS) and GLObal Navigation Satellite System (GLONASS), and for E1 Galileo signals are derived from the float phase at 27,000 m height, and the specular points are geolocalized on the Earth's surface. Polarimetric ratio (Γ /Γ ) maps over boreal forests are shown to be in the range 2-16 dB for the different GNSS codes. This result suggests that the scattering is taking place not only over the soil, but over the different forests elements as well. Additionally to the interpretation of the experimental results a theoretical investigation of the different contributions to the total reflectivity over boreal forests is performed using a bistatic scattering model. The simulated cross-(reflected Left Hand Circular Polarization LHCP) and co-polar (reflected Right Hand Circular Polarization RHCP) reflectivities are evaluated for the soil, the canopy, and the canopy-soil interactions for three different biomass densities: 725 trees/ha, 150 trees/ha and 72 trees/ha. For elevation angles larger than the Brewster angle, it is found that the cross-polar OPEN ACCESSRemote Sens. 2015, 7 13121 signal is dominant when just single reflections over the forests are evaluated, while in the case of multiple reflections the co-polar signal becomes the largest one.

show abstract

Effect of sea roughness on bistatically scattered range coded signals from the Global Positioning System

Cited by 207 publications

References 3 publications

Wind speed measurement using forward scattered GPS signals

Wind speed measurement using forward scattered GPS signals

Detection of buried objects using reflected GNSS signals

First Polarimetric GNSS-R Measurements from a Stratospheric Flight over Boreal Forests

Contact Info

Product

Resources

About