The invention relates to a local phase lock quadrature polarization
free space coherent light
communication device. The local phase lock quadrature polarization
free space coherent light
communication device comprises a single frequency
single mode laser device, a
fiber polarization beam splitter, a
fiber stretcher, a
first light phase modulator, a second light phase modulator, a
data signal generator, a
microwave amplifier, a first
fiber collimator, a second fiber
collimator, a first emission half-wave plate, a second emission half-wave plate, a first polarization
beam splitting prism, a third emission half-wave plate, a second polarization
beam splitting prism, a first rectangular
prism, a first focusing lens, a second focusing lens, a first balance
detector, a
loop filter, a reception half-wave plate, a third polarization
beam splitting prism, a second rectangular prism, a third focusing lens, a fourth focusing lens, a second balance
detector and an A / D converter. The device emits coaxial quadrature polarization
signal light, realizes self-interference reception at a reception end and can effectively overcome a
phase error, a locking phase structure is arranged at an emission end, the structure of the reception end is simplified, and the
system communication rate can be flexibly adjusted with no need for adjusting the light path.