Abstract:
Due to the problem of hardware architecture, the range gating module of the existing mobile satellite laser ranging system has some shortcomings, such as low stability and low reliability. Since it is incompatible with the equipment of the fixed station, it is necessary to develop a new range gating module to improve the operation stability while giving consideration to high integration. Based on the realization principle of range gating and backscattering avoidance, the new range gating module is designed with ARM and FPGA embedded dual core architecture. The module used the ephemeris of lageos1, ajisai and geosynchronous compassi3 satellites to fit the range gating parameters. The test results show that the parameter fitting error of the range gating module is less than 0.01%, and the calculation time of a single expected echo epoch is 34.365 μs at repetition rate of 2 kHz. The average firing frequency loss rate due to the backscattering avoidance is less than 1%. The resolution of range gating is lower than 5 ns at repetition rate of 2 kHz. The output of high frequency gating signal is stable and the module can meet the requirements of repetition frequency applications over 20 kHz. It conforms to the expected results and has practical application value.