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:
Feb. 29, 2000
Filed:
May. 01, 1997
Applicant:
Inventors:
Joel I Javitt, Hillside, NJ (US);
Christopher L Rutledge, Somerset, NJ (US);
Assignee:
AT&T Corp., New York, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
359161 ; 359124 ; 359154 ; 359159 ; 359194 ;
Abstract
Free-space optical transmission of analog information is facilitated by transmitting constant-amplitude pilot information with the other information. The amount of attenuation of the pilot information at the receiver is detected and used to control the amount by which received information is amplified. In this way the deleterious effects of free-space optical attenuation are substantially eliminated. The pilot information may be transmitted either via its own separate light frequency or wavelength, or as a distinguishable part of a larger quantity of information that is used to modulate one light frequency or wavelength.