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:
Jul. 15, 1986
Filed:
Jun. 21, 1984
Robert W Scarr, Stansted, GB;
John Bingham, Dunmow, GB;
International Standard Electric Corporation, New York, NY (US);
Abstract
In an optical fiber FDM system, the carriers are derived from the output of a high quality Master Oscillator, which output at frequency f.sub.0 is applied to a Raman Nath modulator (RNM1) whose other input is a frequency f.sub.0 this gives as its outputs (assuming a five channel system) f.sub.0 -2f, f.sub.0 -f, f.sub.0, f.sub.0 +f and f.sub.0 +2f. These are modulated by modulators (CM1, to CM5) with the signals to be sent, and the modulation results combined in a combiner CB for transmission to a remote station. The oscillator output is also sent to the remote stations where it is frequency-shifted by a Bragg modulator (BM) and the resultant similarly dealt with by a Raman Nath device (RNM2) to give five frequencies which are used to demodulate the channels. In an alternative the channel frequencies are switchable.