An OTDM transmitting method and transmitter realizing an OTDM
distortion-free transmission substantially not relying upon dispersion. A
time division multiplexed OTDM signal from an OTDM signal transmitter (1)
enters an optical Fourier transform unit (2). Optical Fourier transform
can be carried out most accurately so long as the optical pulse is a
chirp-free Fourier transform limit pulse. The optical Fourier transform
unit (2) converts the time waveform of the pulse into a signal on the
frequency axis, and an optical inverse Fourier transform unit (2')
converts a spectral shape on the frequency axis into a time waveform
(pulse). An optical fiber transmission line (3) is a transmission line
having an arbitrary dispersion and a polarization mode dispersion. These
dispersions may involve a time variation. An OTDM signal receiver (4)
demultiplexes a transmission signal into low-speed optical signals, in a
light region, receives optical pulses for respective channels and
converts them into electric signals.