A vehicle laser Doppler velocimeter configured with three transmitting beams

A laser Doppler velocimeter (LDV) with three transmitting beams is designed to simultaneously measure the three components of vehicle´s velocity, which cannot be achieved in conventional LDV with single or double beam. The system configuration and design method of the LDV is proposed, It is based on all fiber-optics and the signal collecting and processing is accomplished by FPGA and DSP. Some key technologies, including antenna layout, signal process and software design, are introduced. The experimental results indicated that the LDV was able to provide the real-time three-dimensional velocity components for vehicle navigation systems.