United States Patent  [u] Patent Number: 5,241,961
Henry  Date of Patent: Sep. 7,1993
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Primary Examiner—William E. Kamm
Attorney, Agent, or Firm—Woodard, Emhardt,
Naughton, Moriarty & McNett
A synchronous telemetry receiver and receiving method for reception from an implantable medical device of a PPM signal including a plurality of bits each having a sync pulse and at least one data pulse of equal amplitude. Capability is provided for restoring correct phase in the event that a sync pulse is missing or incorrectly received for any reason. A high-frequency clock and counter are provided for counting clock pulses during the time interval between each data pulse and its respective sync pulse in order to obtain a measurement of the time interval.
9 Claims, 10 Drawing Sheets
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