PARALLEL SEARCH CIRCUIT FOR A MEDICAL IMPLANT RECEIVER

• US 20100036460A1
• Filed: 08/06/2009
• Published: 02/11/2010
• Est. Priority Date: 08/06/2008
• Status: Abandoned Application

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Pentakota, Visvesvaraya, Ramakrishnan, Sthanunathan, Tangudu, Jawaharlal
• Application Number:
  US12/536,562
• Publication Number:
  US 20100036460A1
• Time in Patent Office: Days
• US Class Current: 607/60
• CPC Class Codes: A61N 1/3727 characterised by the modulation technique

Abstract

Parallel search circuit for a medical implant receiver. The circuit includes a radio frequency receiver that receives a first set of contents of a band of channels. The circuit also includes a processing circuit coupled to the radio frequency receiver to process in parallel a second set of contents of a plurality of channels of the band of channels and to detect a signal in the band of channels.

Claims

1. A method for signaling in a medical implant based system, the method comprising:

receiving a first set of contents of a band of channels by a receiver;

processing in parallel a second set of contents of a plurality of channels from the band of channels; and

detecting a signal in the band of channels based on the processing.

2. The method as claimed in claim 1, wherein the receiver is a medical implant receiver.

3. The method as claimed in claim 1, wherein the processing comprises:

converting the first set of contents into digital samples.

4. The method as claimed in claim 3, wherein the second set of contents comprises:

the digital samples of the first set of contents.

5. The method as claimed in claim 3, wherein the processing further comprises:

storing the digital samples of the first set of contents in a storage device; and

selecting the second set of contents from the digital samples.

6. The method as claimed in claim 1, wherein processing content of each channel comprises:

correcting a frequency offset to obtain a filtered content; and

correlating the filtered content with a predefined sequence.

7. The method as claimed in claim 1, wherein processing content of each channel comprises:

hypothesizing on one or more frequency offsets; and

correlating filtered content obtained from each hypothesis with a predefined sequence.

8. The method as claimed in claim 7, wherein the predefined sequence is one of:

a pseudorandom sequence;

a gold coded sequence;

a barker sequence; and

a walsh code sequence.

9. The method as claimed in claim 1, wherein processing content of each channel comprises:

determining a peak value of a sample in an output of the processing; and

checking the peak value against a threshold.

10. The method as claimed in claim 1, wherein processing content of each channel comprises:

determining a ratio of a peak value of a sample in an output of the processing to an average value of off-peak samples in the output of the processing; and

checking the ratio against a threshold.

11. The method as claimed in claim 1 and further comprising:

identifying a channel that carries the signal.

12. A method for signaling in a medical implant based system, the method comprising:

receiving a first set of contents of a band of channels by a receiver;

converting the first set of contents into digital samples;

storing the digital samples of the first set of contents;

selecting a subset of the digital samples, the subset comprising contents of a plurality of channels from the band of channels;

correcting one or more frequency offsets in the subset in parallel to obtain a filtered content for each channel;

correlating the filtered content with a predefined sequence; and

detecting a signal in the band of channels based on an output of the correlating.

13. A receiver circuit comprising:

a radio frequency receiver that receives a first set of contents of a band of channels;

a processing circuit coupled to the radio frequency receiver to

process in parallel a second set of contents of a plurality of channels of the band of channels, and

detect a signal in the band of channels.

14. The receiver circuit as claimed in claim 13 and further comprising:

an analog-to-digital converter, coupled to the radio frequency receiver, that converts the first set of contents into digital samples.

15. The receiver circuit as claimed in claim 14 and further comprising:

a storage device, coupled to the analog-to-digital converter, that stores the digital samples.

16. The receiver circuit as claimed in claim 13, wherein the processing circuit comprises:

a plurality of mixers; and

a plurality of filters, a first one of the plurality of filters coupled to a first one of the plurality of mixers, the first one of the plurality of filters selecting content from the first set of contents in conjunction with the first one of the plurality of mixers to form a first path, the first path and the content being corresponding to a first channel.

17. The receiver circuit as claimed in claim 16, wherein the first path of the processing circuit comprises:

at least one mixer that hypothesizes on a frequency offset of the content;

at least one correlator responsive to hypothesizing to correlate filtered content obtained from the hypothesizing with a predefined sequence; and

at least one accumulator that adds correlated content.

18. The receiver circuit as claimed in claim 17, wherein the first path of the processing circuit further comprises:

at least one peak to off-peak estimator that determines a ratio of a peak value of a sample in an output of processing to an average value of off-peak samples in the output of the processing and compares the ratio against a threshold.

19. The receiver circuit as claimed in claim 13 and further comprising:

a state machine circuit, coupled to the processing circuit, that identifies a channel that carries the signal.

20. The receiver circuit as claimed in claim 13, wherein the receiver circuit is a medical implant receiver.