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. 11, 2001
Filed:
Dec. 21, 1998
Koen J. Weijand, Rockanje, NL;
Richard Houben, Berg en Terblijt, NL;
Medtronic Inc., Minneapolis, MN (US);
Abstract
There is provided a telemetry system with a receiver which enables detection of pulsed high frequency data (hf) signals in a manner which suppresses noise which may be present within the high frequency bandwidth. The transmitter carrier, which may be subject to some instability, is encoded at a symbol rate which is generated at a lower frequency than the hf, but which is reliably stable. The receiver detects the phase of each received hf pulse, and generates a phase-locked signal which is synchronized to the transmitter symbol signal. The phase-locked signal in turn is used to demodulate the received pulsed signals. In a specific DSP embodiment, the phase-lock loop has a numerically controlled oscillator which has a center frequency which corresponds to the aliased phase difference between the hf carrier phase and the phase of each pulse, thereby obtaining a signal which carries information as to the exact symbol rate. This information is used either to calculate the timing of a narrow window which gates a pulse detector coincident with each next expected symbol time, or to trigger generation of a replica signal which is used in the detect circuit, thereby providing high resolution detection of the pulses and good noise rejection.