Compact fiber optic geometry for a counter chirp FMCW coherent laser radar

• Main Authors: SLOTWINSKI ANTHONY, REZK MINA
• Format: Patent
• Language: English
• Published: 01.04.2014
• Subjects: ANALOGOUS ARRANGEMENTS USING OTHER WAVES; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; GYROSCOPIC INSTRUMENTS; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION ORRERADIATION OF RADIO WAVES; MEASURING; MEASURING DISTANCES, LEVELS OR BEARINGS; NAVIGATION; PHOTOGRAMMETRY OR VIDEOGRAMMETRY; PHYSICS; RADIO DIRECTION-FINDING; RADIO NAVIGATION; SURVEYING; TESTING

A system and method for determining a measured distance between a measuring device (20A) and an object (21), the system including a first laser source (13) for producing a first light beam (13A) having a first waveform (32) and a first frequency; a second laser source (11) for producing a second light beam (1 IA) having a second frequency, said second light beam (HA) having a second waveform (36), wherein said first frequency is chirped up at the first rate as said second frequency is chirped down at the first rate, and said second frequency is chirped up at the second rate as said first frequency is chirped down at the first rate; an optical element (15) for combining said first light beam (13A) with said second light beam (HA) into a combined light beam path (17), said optical element (15) splitting a returning portion of said combined light beam path (17) into a third light beam (24); and a single detector (23) for receiving said third light beam (24) including two different beat frequencies that are proportional to the measured distance.