Wideband Ocean Altimetry Using Ku-Band and K-Band Satellite Signals of Opportunity: Proof of Concept

Ho, Soon Chye; Shah, Rashmi; Garrison, James L.; Mohammed, Priscilla N.; Schoenwald, A.; Pannu, Randeep; Piepmeier, Jeffrey R.

doi:10.1109/lgrs.2019.2891976

Cited by 13 publications

(6 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For altimetry measurement accuracy, a few cm in delay-precisions from coastal experiments was demonstrated using X-band digital TV signals (Ribó et al, 2014). Also, preliminary results from tower-based experiment that used both Ku and K-band transmissions from a commercial (DirecTV) direct broadcast satellite confirm the validity of the theoretical error model which predicts that the measurement precision from spaceborne receivers will be in the order of 5-6 cm (Shah and Garrison, 2017;Ho et al, 2019).…”

Section: W-soop Overview -Theory and Algorithmsmentioning

confidence: 76%

Requirements for a Coastal Hazards Observing System

et al. 2019

Self Cite

View full text Add to dashboard Cite

Coastal zones are highly dynamical systems affected by a variety of natural and anthropogenic forcing factors that include sea level rise, extreme events, local oceanic and atmospheric processes, ground subsidence, etc. However, so far, they remain poorly monitored on a global scale. To better understand changes affecting world coastal zones and to provide crucial information to decision-makers involved in adaptation to and mitigation of environmental risks, coastal observations of various types need to be collected and analyzed. In this white paper, we first discuss the main forcing agents acting on coastal regions (e.g., sea level, winds, waves and currents, river runoff, sediment supply and transport, vertical land motions, land use) and the induced coastal response (e.g., shoreline position, estuaries morphology, land topography at Frontiers in Marine Science | www.frontiersin.org 1 July 2019 | Volume 6 | Article 348Benveniste et al.Requirements for a Coastal Zone Observing System the land-sea interface and coastal bathymetry). We identify a number of space-based observational needs that have to be addressed in the near future to understand coastal zone evolution. Among these, improved monitoring of coastal sea level by satellite altimetry techniques is recognized as high priority. Classical altimeter data in the coastal zone are adversely affected by land contamination with degraded range and geophysical corrections. However, recent progress in coastal altimetry data processing and multisensor data synergy, offers new perspective to measure sea level change very close to the coast. This issue is discussed in much detail in this paper, including the development of a global coastal sea-level and sea state climate record with mission consistent coastal processing and products dedicated to coastal regimes. Finally, we present a new promising technology based on the use of Signals of Opportunity (SoOp), i.e., communication satellite transmissions that are reutilized as illumination sources in a bistatic radar configuration, for measuring coastal sea level. Since SoOp technology requires only receiver technology to be placed in orbit, small satellite platforms could be used, enabling a constellation to achieve high spatio-temporal resolutions of sea level in coastal zones.

show abstract

Section: W-soop Overview -Theory and Algorithmsmentioning

confidence: 76%

Requirements for a Coastal Hazards Observing System

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…At present, to use wide-bandwidth signals, especially encrypted signals, such as the P(Y) code of GPS, some approaches have been proposed, including partial interferometer [47] and semicodeless technology [48]. In addition, due to the wider frequency spectrum, some other signals from communication satellites have been used to provide more precise altimetry [49]. The proposed methods can also be used to calibrate the bias of the above signals; however, the fitting parameters of the analytical models have to be obtained, and the neural network should be trained again.…”

Section: Discussionmentioning

confidence: 99%

Measurement of the Sea Surface Height with Airborne GNSS Reflectometry and Delay Bias Calibration

et al. 2021

View full text Add to dashboard Cite

Sea surface height can be measured with the delay between reflected and direct global navigation satellite system (GNSS) signals. The arrival time of a feature point, such as the waveform peak, the peak of the derivative waveform, and the fraction of the peak waveform is not the true arrival time of the specular signal; there is a bias between them. This paper aims to analyze and calibrate the bias to improve the accuracy of sea surface height measured by using the reflected signals of GPS CA, Galileo E1b and BeiDou B1I. First, the influencing factors of the delay bias, including the elevation angle, receiver height, wind speed, pseudorandom noise (PRN) code of GPS CA, Galileo E1b and BeiDou B1I, and the down-looking antenna pattern are explored based on the Z-V model. The results show that (1) with increasing elevation angle, receiver height, and wind speed, the delay bias tends to decrease; (2) the impact of the PRN code is uncoupled from the elevation angle, receiver height, and wind speed, so the delay biases of Galileo E1b and BeiDou B1I can be derived from that of GPS CA by multiplication by the constants 0.32 and 0.54, respectively; and (3) the influence of the down-looking antenna pattern on the delay bias is lower than 1 m, which is less than that of other factors; hence, the effect of the down-looking antenna pattern is ignored in this paper. Second, an analytical model and a neural network are proposed based on the assumption that the influence of all factors on the delay bias are uncoupled and coupled, respectively, to calibrate the delay bias. The results of the simulation and experiment show that compared to the meter-level bias before the calibration, the calibrated bias decreases the decimeter level. Based on the fact that the specular points of several satellites are visible to the down-looking antenna, the multi-observation method is proposed to calibrate the bias for the case of unknown wind speed, and the same calibration results can be obtained when the proper combination of satellites is selected.

show abstract

“…Some communication and broadcast satellites are GEO satellites. We will also try to use these satellites for shore-based reflected signal altimetry in the future [33], [34]. In addition, GNSS-R tsunami monitoring technology based on SSH changes can be further developed through the long-term stable characteristics of GEO BDS-R observation area [35].…”

Section: Discussionmentioning

confidence: 99%

Sea Surface Height Estimation by Ground-Based BDS GEO Satellite Reflectometry

Chen

Gao

et al. 2020

IEEE J. Sel. Top. Appl. Earth Observations Remote Sensing

View full text Add to dashboard Cite

Chinese BeiDou Navigation Satellite System (BDS) as a mixed constellation, consists of not only Medium Earth Orbit (MEO) satellites but also Inclined Geosynchronous Orbit (IGSO) and Geostationary Earth Orbit (GEO) satellites, of which the GEO satellites remain visible and stationary in the Asia-Pacific region almost all the time so as to better ensure the reflected signals' stability and continuity, compared to using only MEO satellites in previous GNSS-R remote sensing research. This paper demonstrates ocean altimetry capability using reflected signals from BDS GEO satellite with coastal experiments conducted in Weihai, Shandong, China on July 6 and July 9, 2019. By using only one GEO satellite, the precision of DDM (Delay Doppler Map) and phase altimetry is up to decimeter (close to millimeter) level. And the results show that BDS GEO-R technique can be used to monitor small changes in ocean altimetry with high temporal resolution.

show abstract

Wideband Ocean Altimetry Using Ku-Band and K-Band Satellite Signals of Opportunity: Proof of Concept

Cited by 13 publications

References 11 publications

Requirements for a Coastal Hazards Observing System

Requirements for a Coastal Hazards Observing System

Measurement of the Sea Surface Height with Airborne GNSS Reflectometry and Delay Bias Calibration

Sea Surface Height Estimation by Ground-Based BDS GEO Satellite Reflectometry

Contact Info

Product

Resources

About