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:
Nov. 03, 1992
Filed:
Oct. 02, 1991
Anders G Djupsjobacka, Solna, SE;
Telefonaktiebolaget L M Ericsson, Stockholm, SE;
Abstract
A modulator arrangement comprises two Mach-Zehnder modulators, a main modulator (2) and a compensation modulator (3) having non-linear transmission functions. The modulators (2, 3) are controlled by a modulating control signal (V), via electrodes (16, 17). A carrier wave (S1) from a laser (7) is power divided (a, 1-a) into part-waves in a power divider (5) between the modulators (2, 3). The modulated part-waves (S2, S3) are superimposed at an output (14) to produce a resultant modulated wave (S4). A linearized transmission function between the control voltage (V) and the power of the resultant modulated wave (S4) has a radius of curvature whose length is maximized within a control voltage range, so as to minimize intermodulation distortion. The mean slope of the transmission function is maximized within this range. At a common control voltage (V) for the modulators (2, 3), the modulator arrangement has an optimal transmission function at a length ratio b=.sqroot.3:1 between the modulators (2, 3), and a power ratio between the part-waves of .sqroot.3:9. The main modulator (2) is the shortest and modulates the strongest part-wave.