Optimization of Auxiliary Biaxial Receiver to Detect Blind Zone of Pulsed Coherent Wind Lidar

The conventional pulsed monostatic coaxial coherent Doppler wind lidar (CDWL) has a blind detection zone of tens of meters, causing the loss of near-field wind field data. We propose a novel auxiliary biaxial receiver (ABR) to obtain reliable coherent signals in the blind zones by adding a receiver near the monostatic coaxial transceiver (MCT) to avoid end-face reflections and tailing effects of laser pulses. A specific model of multiple aperture coherent wind detection is established for the ABR system without blind zone problem (BZP). The numerical simulations demonstrate that the biaxial receiver with reasonable design can meet the detection needs of the entire range of the blind zone. By using an ABR with a smaller focal length under appropriate transceiver pointing and general pointing accuracy, the BZP can be solved. The study also exhaustively obtained all parameter combinations that can solve the near-field BZP for a specific system. The results provide a new idea and engineering design guidance for the optical system design of pulsed CDWL without BZP.