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:
Oct. 08, 1996
Filed:
Jun. 14, 1995
Etsuji Mesuda, Atsugi, JP;
Kazuhiko Ishibe, Samukawa-machi, JP;
Anritsu Corporation, Tokyo, JP;
Abstract
A target signal input to a mixer circuit of a frequency converter is frequency-converted to have a low frequency by a signal obtained by frequency-multiplying an output signal from the voltage-controlled crystal oscillator by M. The frequency-converted output is compared with the output signal from the voltage-controlled crystal oscillator by a phase/frequency comparator. A loop filter receives an error signal based on the phase/frequency comparison and performs loop control to lock the phase of the output signal from the voltage-controlled crystal oscillator to the phase of the output signal from the frequency converter. The jitter component of the target signal exhibiting phase variations at a frequency higher than a loop band contained in the error signal is output from a jitter detection filter before the loop filter via a branching circuit. Even if the target signal having a high frequency undergoes a great frequency change, stable, accurate jitter measurements can be performed following the change.