Spatial light transmission system

Abstract

Abstract PURPOSE:To easily design the control characteristic for the control of the frequency of local oscillation light on the reception station side by providing a frequency controller, which corrects the frequency variation of communication laser beam on a transmission line, instead of a frequency stabilizer which stabilizes the oscillation frequency of transmission laser beam. CONSTITUTION:The output laser beam of a transmission laser 12 performs the rough control of the oscillation frequency by a frequency controller 14 which receives a frequency control signal 5 for the purpose of correcting the frequency change on the transmission line. Thereafter, this laser beam is subjected to phase modulation with a transmission signal 3 by an optical modulator 13 and outputted from an optical transmission equipment 1A. Since the laser beam is inputted to a light reception 2A and the frequency variation on the transmission line is corrected, the oscillation frequency is approximately stabilized. Consequently, a received signal is stably demodulated by a demodulator 23 by the control which stabilizes the frequency of beat signal light in a narrow range.

Inventors

• 👤 Kouichi Shiratama
• 👤 白玉　公一

Bibliographic Details