Optical field transmitter and optical field transmission system

An optical field transmission system comprising an optical field transmitter and an optical field receiver, wherein:

• the optical field transmitter comprises a light source, one or more digital-analog converters, and an optical field modulator;
• the optical field transmitter modulates an information signal sampled at predetermined time intervals into an optical field signal and transmitting the optical field signal obtained by the modulation;
• the optical field receiver for receiving the optical field signal transmitted from the optical field transmitter;
• the information signal includes one of:
• multilevel signals arranged irregularly on a complex plane;
• and multilevel signals arranged by combining mutually different numbers of phase values in at least two amplitude values;
• the optical field transmitter further comprises a phase pre-accumulation circuit for outputting phase pre-accumulation complex information obtained by previously accumulating a phase component of the information signal at predetermined time intervals;
• the one or more digital-analog converters each converts the information signal including the output phase pre-accumulation complex information into an analog signal, and inputs the analog signal obtained by the conversion to the optical field modulator;
• the optical field modulator modulates light output from the light source into the optical field signal by using the analog signal, and transmits the optical field signal obtained by the modulation;
• and
• the optical field receiver comprises:
• an optical splitter for splitting the received optical field signal into a plurality of optical signals comprising at least one first optical signal and one second optical signal;
• a first optical delay detection receiver for delay-detecting the one first optical signal with a predetermined delay time, and converting the one first optical signal that has been delay-detected into a first electrical signal;
• a second optical delay detection receiver for delay-detecting the one second optical signal with a predetermined delay time by a phase difference in which a phase thereof is shifted from a phase of the first optical delay detection receiver by 90 degrees, and converting the one second optical signal that has been optically-delay-detected into a second electrical signal;
• and
• a complex information combining circuit for receiving the first electrical signal and the second electrical signal input at the same timing.