The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 09, 2003
Filed:
Jun. 05, 2000
Junji Shigeta, Utsunomiya, JP;
Toshihiko Myojo, Yokohama, JP;
Yasuhiro Takahashi, Ageo, JP;
Kazuo Moritomo, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A bidirectional optical space transmission system is made up of a pair of optical transmission apparatus. Each optical transmission apparatus comprises a signal generating circuit for generating a pilot signal, a multiplexing section for multiplexing the pilot signal and a main signal to be transmitted, an electrooptic converter section for emitting an optical signal on the basis of the signal produced by the multiplexing process, a light receiving element for receiving an optical signal transmitted from the partner optical transmission apparatus and detecting a pilot signal contained therein, and a demodulation circuit for demodulating the pilot signal detected by the light receiving element. Pilot signals multiplexed with main signals to be transmitted through the bidirectional optical transmission system are subjected to spreading modulation and demodulated for spreading by the demodulation circuit.