Abstract's details
A SAR altimetry End-to-End simulation and processing chain
CoAuthors
Event: 2018 Ocean Surface Topography Science Team Meeting
Session: Others (poster only)
Presentation type: Type Poster
Contribution: PDF file
Abstract:
The purpose of this abstract is to present the SAR altimetry End-to-End simulation and processing chain developed by Aresys, that is composed by three main modules
1) Level0 data simulator: this module is in charge of performing a time domain simulation, where the echoes originated by a given number of point target placed on ground are accumulated at PRF rate to obtain simulated raw data. It can be basically decomposed in three submodules: (i) the scene generator that simulates the on ground scene according to the desired scenario (e.g. open ocean, sea ice, land ice), (ii) the raw data generator that accumulates the echoes from each point at PRF rate to obtain simulated raw data, and (iii) the radar altimeter simulator that is model of the receiving chain of the instrument to generate the Level0 data.
2) Generic Altimetric Processor Level1: this module is in charge of generating Level1 products (Level1A, Level1BS and Level1B) exploiting a flexible and fully configurable Delay/Doppler processing chain. In particular, this processor allows to select different methods for the Surface Sample placing (i.e. based on fixed angle separation or at nadir of bursts) and different methods for the azimuth beamforming (i.e. based on FFT or on DFT or on CZT [1]). Additionally different stack weighting methods are also configurable (e.g. [2]).
3) Generic Altimetric Processor Level2: this module is in charge of retrieving the geophysical parameters from Level1B products. The developed retracker is based on a semi-analytical waveform model [3] that allows for modeling with the same approach LRM, SAR and SARin waveforms.
The SAR altimetry end-to-end simulation and processing chain allows to simulate any instrument with the selected chronogram and it allows for the corresponding performance assessment by comparison of the geophysical parameters given as input to the scene generation with the geophysical parameters retrieved after waveform retracking.
[1] P. Guccione, "Beam Sharpening of Delay/Doppler Altimeter Data Through Chirp Zeta Transform," in IEEE Transactions on Geoscience and Remote Sensing, vol. 46, no. 9, pp. 2517-2526, Sept. 2008.
[2] M. Scagliola, S. Dinardo and M. Fornari, "An extended analysis of along-track antenna pattern compensation for SAR altimetry," 2015 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Milan, 2015, pp. 1238-1241.
[3] L. Recchia, M. Scagliola, D. Giudici and M. Kuschnerus, "An Accurate Semianalytical Waveform Model for Mispointed SAR Interferometric Altimeters," in IEEE Geoscience and Remote Sensing Letters, vol. 14, no. 9, pp. 1537-1541, Sept. 2017.
1) Level0 data simulator: this module is in charge of performing a time domain simulation, where the echoes originated by a given number of point target placed on ground are accumulated at PRF rate to obtain simulated raw data. It can be basically decomposed in three submodules: (i) the scene generator that simulates the on ground scene according to the desired scenario (e.g. open ocean, sea ice, land ice), (ii) the raw data generator that accumulates the echoes from each point at PRF rate to obtain simulated raw data, and (iii) the radar altimeter simulator that is model of the receiving chain of the instrument to generate the Level0 data.
2) Generic Altimetric Processor Level1: this module is in charge of generating Level1 products (Level1A, Level1BS and Level1B) exploiting a flexible and fully configurable Delay/Doppler processing chain. In particular, this processor allows to select different methods for the Surface Sample placing (i.e. based on fixed angle separation or at nadir of bursts) and different methods for the azimuth beamforming (i.e. based on FFT or on DFT or on CZT [1]). Additionally different stack weighting methods are also configurable (e.g. [2]).
3) Generic Altimetric Processor Level2: this module is in charge of retrieving the geophysical parameters from Level1B products. The developed retracker is based on a semi-analytical waveform model [3] that allows for modeling with the same approach LRM, SAR and SARin waveforms.
The SAR altimetry end-to-end simulation and processing chain allows to simulate any instrument with the selected chronogram and it allows for the corresponding performance assessment by comparison of the geophysical parameters given as input to the scene generation with the geophysical parameters retrieved after waveform retracking.
[1] P. Guccione, "Beam Sharpening of Delay/Doppler Altimeter Data Through Chirp Zeta Transform," in IEEE Transactions on Geoscience and Remote Sensing, vol. 46, no. 9, pp. 2517-2526, Sept. 2008.
[2] M. Scagliola, S. Dinardo and M. Fornari, "An extended analysis of along-track antenna pattern compensation for SAR altimetry," 2015 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Milan, 2015, pp. 1238-1241.
[3] L. Recchia, M. Scagliola, D. Giudici and M. Kuschnerus, "An Accurate Semianalytical Waveform Model for Mispointed SAR Interferometric Altimeters," in IEEE Geoscience and Remote Sensing Letters, vol. 14, no. 9, pp. 1537-1541, Sept. 2017.