CAJ | 학술논문

基于激光雷达外差探测理论，给出自由空间和光纤耦合两种模式下外差效率的解析表达式，并通过参数代换使两者具有统一的形式；结合此表达式以及湍流环境下的信噪比公式，仿真给出了地基与天基外差探测激光雷达系统不同探测距离处的最优望远镜和截断因子。研究结果表明地基系统信噪比随着望远镜孔径变化比较陡峭，存在最优望远镜孔径和截断因子，如若取值不恰当，会造成系统信噪比巨大损失；而天基平台下回波信号的信噪比随着光学收发器孔径先增加后保持平稳，孔径取值需要综合考虑成本和信噪比，最优化的截断因子均为80%。此研究对外差探测激光雷达设计理论的发展及系统器件的最优化配置提供了理论依据。
기우격광뢰체외차탐측이론，급출자유공간화광섬우합량충모식하외차효솔적해석표체식，병통과삼수대환사량자구유통일적형식；결합차표체식이급단류배경하적신조비공식，방진급출료지기여천기외차탐측격광뢰체계통불동탐측거리처적최우망원경화절단인자。연구결과표명지기계통신조비수착망원경공경변화비교두초，존재최우망원경공경화절단인자，여약취치불흡당，회조성계통신조비거대손실；이천기평태하회파신호적신조비수착광학수발기공경선증가후보지평은，공경취치수요종합고필성본화신조비，최우화적절단인자균위80%。차연구대외차탐측격광뢰체설계이론적발전급계통기건적최우화배치제공료이론의거。
In this paper, the heterodyne efficiency analytical expression under both free-space and fiber-coupled detect mode of the coaxial system are unified through the parameter substitution, based on Lidar heterodyne detection theory. Combined this formula with the signal-to-noise ratio(SNR) under turbulent environment, the optimum values of the aperture and the truncation factor under different detection range are obtained for ground-based and Spaceborne system. The results show that the SNR of the ground-based Lidar is relatively steep as the optical transceiver aperture changes, the optimum truncation factor is 80%during the whole detect range. But if the aperture selected is not appropriate, the system SNR will loss greatly;For Spaceborne Lidar the SNR is first increased and then stable as the optical transceiver aperture increased, the optimum telescope aperture should be balanced between the cost and SNR, and the optimum truncation factor is also 80%. The research has important theoretical significance and practical value both for the development of detection theory and optimal configuration of the heterodyne detection Lidar.