Coherent Doppler Lidar (CDL) systems are suitable for wind sensing of localized regions under
clear weather conditions. Especially, a 1.5 μm all-fiber wind sensing CDL system has many advantages
since telecomm fibers and fiber-based components, which have reached technical maturity, can be used. We
have developed all-fiber CDL systems during this decade, and in this chapter we introduce our development
in addition to the basic theory for system design. After the demonstration of wind sensing performance
using the prototype model, we have developed the product model by refining the prototype model. The
product model consists of a compact fiber-based optical transceiver unit, an optical antenna unit that
includes a wedge scanner, and a Field Programmable Gated Array (FPGA)-based real-time signal
processing unit. All-fiber CDL systems can be used for various industrial applications, such as
meteorological monitoring, wind survey for wind power generation, and aviation safety.
Keywords: Doppler lidar, coherent laser radar, turbulence, fiber laser, fiber amplifier, acousto-optic
modulator, polarization control, wind sensing, wind velocity, wind direction.
