In-Orbit External Calibration Method for Synthetic Aperture Radiometer
| Autor: | Pengju Jin, Wenxin Chen, Rongchuan Lv, Guangnan Song, Wang Jiakun, Xiaojiao Yang, Hailiang Lu, Pengfei Li, Yinan Li, Hao Li |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Synthetic aperture radar
Atmospheric Science 010504 meteorology & atmospheric sciences Channel (digital image) Calibration (statistics) Computer science Image quality Geophysics. Cosmic physics ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION 02 engineering and technology 01 natural sciences 0202 electrical engineering electronic engineering information engineering Electronic engineering Point (geometry) Antenna error Computers in Earth Sciences TC1501-1800 0105 earth and related environmental sciences Radiometer synthetic aperture radiometer QC801-809 Astrophysics::Instrumentation and Methods for Astrophysics 020206 networking & telecommunications Azimuth Ocean engineering external calibration Antenna (radio) in-orbit |
| Zdroj: | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, Vol 14, Pp 3763-3773 (2021) |
| ISSN: | 2151-1535 |
| Popis: | The effective calibration of systematic errors is a precondition for high-quality images from a synthetic aperture radiometer system. The receiving channel errors can be relatively well calibrated, but antenna errors cannot be calibrated effectively in-orbit. This article proposes an in-orbit external antenna error calibration method for synthetic aperture radiometers using external calibration point sources on the ground. Simulation and experimental results demonstrate the accuracy and feasibility of the method. The layout of on-ground calibration point sources was then explored. Our results indicate that is sufficient to adjust the power of the calibration point sources when SNR is 30 dB, and that the calibration requirements can initially be met with three calibration point sources. If better calibration effect is required, eight calibration point sources are sufficient. Nonrepeated and uniform azimuth angle schemes appear to be the optimal layout for operating the proposed method, but adjustments can be made as necessary to suit the situation at hand. Finally, a feasible implementation scheme was established. The proposed method has certain reference value in terms of image quality improvement and practical engineering applications. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|