Patent ID: 8508722

Claim:
A velocimeter comprising: a coherent source configured to produce a coherent beam; a modulation system configured to add a frequency shift to the coherent beam to produce a modulated beam; an optical amplifier configured to amplify the modulated beam; a transceiver configured to receive the amplified beam via a first optical fiber, the transceiver including an amplifier configured to further amplify the amplified beam, and the transceiver configured to transmit the further amplified light to a target region and to receive reflected light from the target region; wherein the modulation system is located between the coherent source and the transceiver, and a receiver coupled to the transceiver via a second optical fiber and coupled to the coherent source via a third optical fiber, the receiver configured to: receive the reflected light from the transceiver, receive a reference light from the coherent source, and determine a Doppler shift based on the reflected and reference light.