Six-degree-of-freedom high-precision baseline measurement system and method based on femtosecond optical combs

Abstract

The invention discloses a six-degree-of-freedom high-precision baseline measurement system and method based on femtosecond optical combs. The six-degree-of-freedom high-precision baseline measurementsystem comprises the first femtosecond optical comb, the second femtosecond optical comb, a Michelson interference system, a third spectroscope BS3, a third optical grating G3, a fourth optical grating G4, a CCD, a first photoelectric detector PD1, a second photoelectric receiving system, a third photoelectric receiving system, a fourth photoelectric receiving system and a fifth photoelectric receiving system. Absolute distance measurement of the long baseline system is achieved, and the difficult problem that as for a traditional ranging technology, wide range and high precision ranging is difficult to achieve simultaneously is effectively solved.

Description

technical field [0001] The invention belongs to the technical field of interference synthetic aperture radar, in particular to a six-degree-of-freedom high-precision baseline measurement system and method based on a femtosecond optical comb. Background technique [0002] Interferometric Synthetic Aperture Radar (InSAR) is one of the most important remote sensing methods at present. The InSAR system extracts surface elevation information through the interference processing of two radar images covering the same area. The InSAR systems currently under development all have ultra-long baselines. The baseline length between single-satellite antennas ranges from several meters to hundreds of meters, and the baseline length between dual-satellite formation antennas ranges from hundreds of meters to several kilometers. Under the condition of such an ultra-long baseline, the measurement accuracy of the baseline is one of the most critical factors affecting the accuracy of satellite el...

AI Technical Summary

Problems solved by technology

[0003] The current baseline measurement system generally uses a combined measurement scheme of a laser rangefinder and a digital camera, such as the SRTM system in the United States. The camera is used to track the distance and angle changes of the target mirror on the antenna. However, due to the insufficient measurement accuracy of the camera in the line of sight direction, It is also necessary to use a laser rangefinder to measure the line-of-sight displacement, so the measurement system is relatively complex, and the traditional laser rangefinder has low measurement accuracy while meeting a large range, and the accuracy of the camera is also limited by target extraction when it is used for angle measurement The algorithm error and the pixel size of the camera

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