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. 11, 1995
Filed:
Dec. 08, 1993
Heinz B Mader, Weinfelden, CH;
Telefonaktiebolaget L M Ericsson, Stockholm, SE;
Abstract
A circuit for regenerating a clock signal from an NRZ encoded signal. The NRZ signal is filtered, differentiated, and applied to a nested phase-locked loop. The main loop of the phase-locked loop includes a voltage controlled crystal oscillator. The inner loop of the nested phase-locked loop includes a voltage controlled oscillator which multiplies the frequency of the signal provided by the crystal oscillator to obtain the regenerated clock signal. Tunable low pass filters are used in the differentiating circuit as delay elements. The voltage controlled oscillator includes a tunable low pass filter and an integrator. The control voltage for the inner loop voltage controlled oscillator is used to control the low pass filters of the differentiating circuit in a frequency locked loop.