Self-adaptive match algorithm for transmitter–receiver in the middle and upper atmospheric lidar

A precise matching is required between the emitted laser beam and Field-of-View (FOV) of the received telescope to ensure useful observation of middle and upper atmospheric lidar. Nowadays, manual matching is commonly used, but it is time-consuming and has poor stability. Automatic matching is still hard to meet the actual application requirement because it is challenging to balance accuracy and efficiency. Thus, in this paper, a self-adaptive matching algorithm is proposed. In this process, the correlation coefficient between the echo signal and the standard pattern is considered as the matching criterion. It adaptively updates the adjustment step according to the current position’s matching state and uses the correlation coefficient’s increasing gradient as the adjustment direction. The above matching process is iteratively conducted until meeting the convergence condition. The matching process is within 3∼5min. These results suggest that the proposed automated matching algorithm can play an important role in unattended atmospheric lidars. •A new method to evaluate the matching state of lidar transmitter and receiver was proposed.•The step size and path optimization can be automatically operated according to the current matching state.•The self-adaptive algorithm can greatly improve the efficiency.