Yang Wenbo, Zhao Yan, Fan Cunbo, Kang Zhe, Liu Peiyu
Appl Opt. 2021 Jan 10;60(2):296-305. doi: 10.1364/AO.408434.
The range gate generator (RGG) is a key device in kilohertz (kHz) satellite laser ranging systems. The RGG at Changchun station is an integrated circuit composed of discrete components. Using this RGG at high repetition rates can result in the loss of data, and the low resolution of internal time can lead to inaccurate data points. In this paper, starting from the principle of noise suppression by range gate control, we propose a method of range gate control with high repetition rates, high accuracy, and strong universality, and we implement a RGG based on the heterogeneous system architecture of a field-programmable gate array plus a digital signal processor. The average of the intervals between the internal time of the embedded RGG and the external standard time is 48.268 ns, and the accuracy of the range gate time is less than 1.5 ns. The test results indicate that the embedded RGG can satisfy the demand for centimeter-level accuracy with satellite laser ranging. Compared with the original RGG at Changchun station, the embedded RGG has significantly improved time resolution, repetition rate of laser ranging, and system upgrade and maintenance. At present, Changchun station is carrying out a short-term stability test on the embedded RGG.
距离门发生器（RGG）是千赫兹（kHz）卫星激光测距系统中的关键设备。长春站的RGG是一个由分立元件组成的集成电路。在高重复率下使用该RGG会导致数据丢失，并且内部时间分辨率低会导致数据点不准确。本文从距离门控制噪声抑制原理出发，提出了一种高重复率、高精度、强通用性的距离门控制方法，并基于现场可编程门阵列加数字信号处理器的异构系统架构实现了一个RGG。嵌入式RGG内部时间与外部标准时间间隔的平均值为48.268 ns，距离门时间精度小于1.5 ns。测试结果表明，嵌入式RGG能够满足卫星激光测距厘米级精度的要求。与长春站原来的RGG相比，嵌入式RGG在时间分辨率、激光测距重复率以及系统升级维护方面都有显著提高。目前，长春站正在对嵌入式RGG进行短期稳定性测试。
