High-precision time synchronization information generation system for remote sensing camera

Abstract

The invention discloses a high-precision time synchronization information generation system for a remote sensing camera, thereby solving problems of the large time synchronization error and fluctuation caused by accumulation of camera time synchronization errors with the interval time of a time synchronization information acquisition moment and a pulse per second falling edge in one second in theexisting method. The system comprises an asynchronous serial communication interface chip, a GNSS second pulse level conversion chip, a crystal oscillator and an imaging control FPGA. After the falling edge of a GNSS pulse per second is delayed by at least two maximum row / frame periods of a camera, generation of high-precision time synchronization information is triggered; and with three-stage latching, the high precision and correctness of the high-precision time synchronization information inserted into auxiliary data of the remote sensing camera image are ensured. According to the invention, the higher camera time synchronization precision can be realized; the camera time synchronization error cannot be accumulated with the time interval between the time synchronization information acquisition moment and the drop of the pulse per second, so that the requirement on the frequency stability of the crystal oscillator is reduced; and the development cost of the remote sensing camera is reduced while the camera time synchronization precision is improved.

Description

technical field [0001] The invention relates to a remote sensing camera, in particular to a high-precision time synchronization information generation system for a remote sensing camera. Background technique [0002] Remote sensing cameras include cameras that use satellites and other spacecraft or aircrafts as observation platforms to perform remote sensing on the ground. To achieve the required plane positioning accuracy, elevation accuracy or attitude measurement accuracy, the remote sensing camera needs to ensure the time of the camera, the observation platform and the gyroscope, etc. Synchronize with other units. The high-precision time synchronization information includes the line / frame number of the image, and the time code corresponding to the starting moment of the exposure of the line / frame image. The time code is composed of a second value and a microsecond value, where the second value is the current time relative to the timing time reference (such as January 1,...

AI Technical Summary

Problems solved by technology

[0007] The present invention aims at that the plane positioning accuracy, elevation accuracy or attitude measurement accuracy of the remote sensing camera is affected by the camera time synchronization accuracy, while the camera time synchronization error existing in the existing method varies with the timing information collection time and the falling edge of the second pulse within 1 second. To solve the problem of large and fluctuating time synchronization errors caused by the accumulation of time intervals, a high-precision time synchronization information generation system for remote sensing cameras is provided

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