| 摘要 |
PURPOSE:To improve the speed of information transmission and a signal to noise ratio by utilizing the state of polarization, frequency and phase of light waves as individual encoded state selecting one of them, and transmitting to a remote as a code string, making other light waves interfere with it and reproducing obtained information. CONSTITUTION:A luminous flux corresponding to information to be transmitted is emitted from a ray 1, and a polarization state modulator 2, a frequency modulator 3, a phase modulator 4 and a amplitude modulator 5 are operated successively by a code controller 7 to which a code generator 6 is connected. Then, the output from the modulator 5 is transmitted to a remote place through a transmission medium 8, and inputted to an interfering device 11, and the state of polarization is decided by using a polarizing state judging device 9, and interfered by a luminous flux from a station light source 10. Then, frequency, phase, amplitude are decided by using a frequency deciding device 13, a phase deciding device 14 and an amplitude modulator 15, and a code string is reproduced by a code reproducer 17. Thus, frequency component other than transmission frequency is removed by utilizing heterodyne detection, and large capacity and high quality transmission is performed. |
