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:
Apr. 20, 1982
Filed:
Jun. 23, 1980
John T Peoples, Berkeley Heights, NJ (US);
Other;
Abstract
Circuitry for detecting and estimating the frequency of a tone signal comprises: sampler (20) to discretize the tone signal into samples; discrete-time filter means (21) for processing the samples; control means (30) including oscillator (31) for driving the sampler and clock generating means (32, 33 and 34) for developing a set of clocking signals to sequentially drive the filter means, this set comprising the frequency of the oscillator and preselected submultiples thereof; threshold signal (24) indicative of the strength of the tone signal; comparator (22) for providing a resultant indication of the comparison between the threshold signal and the output of the filter means; and decoder (23) for converting the set of resultant indications obtained sequentially during each clock signal to yield the output estimate. Thus, the circuitry relies on the use of a single discrete-time filter initially driven by a filter that is successively expanded in correspondence to a clock which is successively decimated.