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:
Dec. 26, 2000
Filed:
May. 22, 1997
Paul S Marston, Cambridge, GB;
Evert D Van Veldhuizen, Veldhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A receiving apparatus has a clock frequency generating circuit comprising in a first embodiment a low cost oscillator whose frequency is higher than the wanted clock frequency and in a second embodiment a low cost oscillator whose frequency can be higher or lower than the wanted clock frequency. By means of subtracting pulses from (first embodiment) or adding/subtracting pulses (second embodiment) to/from the output of the low cost oscillator, a clock frequency is generated which is stable within a specified tolerance range. More particularly, the receiving apparatus comprises a circuit (10,12) for receiving a transmitted signal, a circuit (14, 16) for deriving a repetitive reference signal from the received transmitted signal, clock signal generating circuit (22, 24, 32) for generating a clock signal having a frequency corresponding substantially to a desired frequency, and a circuit (36, 42, 46) for determining whether the clock frequency generated in respective time periods between successive reference signals varies relative to an arbitrarily set value, the circuit providing a control signal which is used to adjust the frequency of the generated clock signal.