The invention discloses a coherent
optical module and an
optical communication system, and relates to the technical field of communication, the
optical module comprises: a sending end, wherein a first optical splitter divides the output of a
laser into one path of local oscillation light and N paths of optical carriers with equal power, the local oscillation light is sent out through a first
circulator after coarse tuning, each coherent
optical transmitter receives a group of modulated four-path electric signals, modulates the modulated four-path electric signals and one path of optical carrier into polarization
multiplexing signal light, and transmits the polarization
multiplexing signal light through a second
circulator; and a receiving end receives the local oscillation light through a first
circulator, amplifies the local oscillation light through an
amplifier, divides the local oscillation light into N paths of local oscillation light through a second optical splitter, and finely adjusts the local oscillation light through finely adjustable
delay lines respectively. Each polarization-independent coherent optical
receiver receives
signal light of the
optical link from the second circulator in a one-to-one manner, performs coherent
frequency mixing and
photoelectric conversion on the
signal light and one path of finely adjusted local oscillation light to obtain a group of four-path electric signals, and outputs the four-path electric signals to the N-channel coherent optical modulation and
demodulation DSP
chip for
demodulation. According to the invention, low-cost, low-power-consumption and high-capacity short-distance optical
interconnection can be realized.