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:
Dec. 09, 2003
Filed:
Mar. 10, 2000
Dennis M. Hall, Manhattan Beach, CA (US);
Raymond K. DeLong, Palos Verdes Estates, CA (US);
Donald G. Heflinger, Torrance, CA (US);
Peter M. Tanner, Redondo Beach, CA (US);
Northrop Grumman Corporation, Los Angeles, CA (US);
Abstract
An optical communication system ( ) is provided for transmitting a multi-rate data signal between a transmitter ( ) and a receiver ( ) in a power efficient manner. The optical communication system ( ) includes an optical source ( ) that supplies an optical carrier signal; an encoder ( ) that receives and encodes a data signal; an external phase modulator ( ) that modulates the optical carrier signal with the encoded data signal, such that the modulator ( ) varies the duty factor of the modulated optical signal based on the encoded data signal; and an optically saturated erbium doped fiber amplifier ( ) that amplifies the modulated optical signal prior to transmission by the transmitter ( ). In accordance with the present invention, the modulation scheme of the optical communication system ( ) varies the duty cycle of the modulation to attain power efficiency during periods of low data demand. In an alternative modulation scheme, data bits are encoded using bi-phase mark encoding and are transmitted in variable-length blocks.