APPARATUS AND METHODS FOR SEARCHING AND SELECTING AN RF TELEMETRY CHANNEL TO ESTABLISH A LINK WITH AN ACTIVE MEDICAL DEVICE

• US 20110285545A1
• Filed: 05/19/2011
• Published: 11/24/2011
• Est. Priority Date: 05/19/2010
• Status: Active Grant

• Current Assignee: Sorin CRM SAS (MicroPort Scientific Corp.)
• Original Assignee: Sorin CRM SAS (MicroPort Scientific Corp.)
• Inventors: Scordilis, Thierry
• Granted Patent: US 8,823,547 B2
• Time in Patent Office: Days
• US Class Current: 340/870.04
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data
• CPC Class Codes: A61N 1/37276 characterised by means for reducing power consumption during telemetry
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

An apparatus and method for searching and selecting an RF telemetry channel to establish a link between an active medical device and a remote device is disclosed. In the absence of any communication request, the available communication channels are scanned periodically to perform a long-term analysis. For each channel, a long-term indicator (iCLT) that is representative of a long-term availability is generated. Upon receipt of a communication request from the remote device, the communication channels are scanned to perform a short-term analysis, a short-term indicator (iCCT) that is representative of the short-term availability is generated. The short-term indicator is weighted by the long-term indicator, to generate a weighted short-term indicator (iCP). Based on the weighted short-term indicator, a communication channel is selected as the communication channel for the communication request.

Claims

1. A method for searching and selecting a communication channel among a plurality of channels, prior to the establishment an RF telemetry link between a remote device and an active medical device, comprising:

establishing a communication in progress with the remote device;

during an absence of a communication request from the remote device, periodically conducting a first scanning and analysis (22) of said plurality of channels and, for each channel, determining and storing a first indicator representative of a long-term availability;

receiving the communication request from the remote device;

in response to the communication request, conducting a second scanning and analysis (30) of said plurality of channels and, for each channel, determining and storing a second indicator representative of a short-term availability; and

selecting (36) the communication channel from the plurality of channels based on said first and second indicators,

wherein said first indicator is a long-term indicator (iCLT) representative of the long-term availability,

the second indicator is a short-term indicator (iCCT) representative of the short-term availability,

a weighted short-term indicator is generated by weighting (34) of the short-term indicator by the long-term indicator, and

said communication channel is selected based on the weighted short-term indicator.

2. The method of claim 1, wherein said first or second analysis (22, 30) further comprises comparing (44) a signal level (RSSI) of each channel to a predetermined threshold level of baseline noise.

3. The method of claim 2, wherein said first or second analysis further comprises, for each channel whose signal level is above the predetermined threshold level of baseline noise, discriminating a signal type (48, 50, 52) by differentiating a data frame signal and a noise signal.

4. The method of claim 3, wherein the step of discriminating a signal type further comprises:

low-pass filtering (48) signals over a temporal window of a predetermined duration;

comparing the filtered signal (RSSI_BF) and the unfiltered signal (RSSI); and

generating a first indicator of signal type based on the comparison of the filtered signal and the unfiltered signal.

5. The method of claim 4, wherein the step of discriminating further comprises:

detecting (50) a peak signal level;

comparing the signal peak level (RSSI_PEAK) and the filtered signal (RSSI_BF); and

generating a second indicator of signal type based on the comparison of the peak signal level and the filtered signal.

6. An apparatus for communication with a remote device comprising:

an attenuator for receiving signals on a plurality of channels from the remote device;

a channel filter for selectively receiving signals on a selected channel of the plurality of channels; and

a means for searching and selecting a communication channel among the plurality of channels, prior to the establishment an RF telemetry link with the remote device,

wherein the means for searching and selecting establishes the RF telemetry link comprises;

means for a first analysis (22), the first analysis being periodically conducted for each channel of said plurality of channels;

means for determining and storing a first indicator representative of a long-term availability for each channel of the plurality of channels;

means for a second analysis (30), the second analysis being conducted for each channel of said plurality of channels in response to a communication request from the remote device;

means for determining and storing a second indicator representative of a short-term availability for each channel of the plurality of channels; and

means for selecting (36) the communication channel from said plurality of channels based on said first and second indicators,

wherein said first indicator is a long-term indicator (iCLT) representative of the long-term availability,

wherein the second indicator is a short-term indicator (iCCT) representative of the short-term availability,

wherein a weighted short-term indicator is generated by weighting (34) of the short-term indicator by the long-term indicator, and

wherein said communication channel is selected based on the weighted short-term indicator.

7. The apparatus of claim 6, wherein said means for the first or second analyses (22, 30) further comprises means for comparing (44) a signal level (RSSI) of each channel to a predetermined threshold level of baseline noise.

8. The apparatus of claim 7, wherein said means for the first or second analyses further comprises, for each channel whose signal level is above the predetermined threshold level of baseline noise, means for discriminating a signal type (48, 50, 52) by differentiating a data frame signal and a noise signal.

9. The apparatus of claim 8, wherein the means for discriminating a signal type further comprises:

low-pass filter (48) filtering the received signals over a temporal window of a predetermined duration;

comparator for comparing the filtered signal (RSSI_BF) and the unfiltered signal (RSSI); and

means for generating a first indicator of signal type based on the comparison of the filtered signal and the unfiltered signal.

10. The apparatus of claim 9, wherein the means for discriminating further comprises:

peak signal level detector (50);

comparator for comparing the signal peak level (RSSI_PEAK) and the filtered signal (RSSI_BF); and

means for generating a second indicator of signal type based on the comparison of the peak signal level and the filtered signal.