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. 27, 1996
Filed:
Jul. 07, 1994
Eitan Gertel, Lansdale, PA (US);
Mark S Colyar, Newtown, PA (US);
AEL Industries, Inc., Lansdale, PA (US);
Abstract
A variable sensitivity compensation network for a Mach-Zender optical modulator comprising first and second pilot signal sources f.sub.1 and f.sub.2, a signal coupler for combining the pilot signals with an RF information signal for modulating a bias-controlled Mach-Zender optical modulator, a variable sensitivity feedback loop comprising an optical detector for detecting the pilot signals from the modulator output, a bandpass filter for selecting the sum frequency f.sub.1 and f.sub.2, a voltage variable attenuator for adjusting the sensitivity of the loop, a logarithmic compression circuit for compressing the f.sub.1 and f.sub.2 signal level from the variable attenuator, means for measuring the signal level, means for controlling the variable attenuator and means for producing an analog bias signal for controlling the operating point of the Mach-Zender modulator. The measuring and controlling means include a microprocessor.