RESUMEN
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. While maintaining the long-range detection capabilities of pulsed lidar, we introduce a novel auxiliary biaxial receiver (ABR) aimed at acquiring dependable coherent signals within blind zones. This is achieved by incorporating a receiver in close proximity to the monostatic coaxial transceiver (MCT), thereby mitigating end-face reflections and laser pulse tailing effects. 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.
RESUMEN
OBJECTIVE: To investigate the value of high-frequency stimulation ABR in the diagnosis and treatment of posterior circulation ischemia. METHOD: Twenty-three patients complaining vertigo diagnosed by neurologist were selected to accept the examination of high-frequency stimulation ABR. After two weeks of treatment, they were tested again. At the same time,20 healthy persons were chosen as control group. The data were analyzed. RESULT: The patients had longer ABR latency and wave interval than the normal controls, and the results improved after the proper treatment. CONCLUSION: High-frequency stimulation ABR can be used to facilitate the diagnosis and to evaluate the therapeutic effect of posterior circulation ischemia.
