Friday, May 05, 2006

Wireless Medical Telemetry Systems

Telemetry has been around for a long time such as in the utility business for meter reading. A more recent use case is the medical industry which uses biotelemetry to transmit a patient’s condition – heart rate, temperature, etc, to a wireless receiver that can monitor and provide data to healthcare provider.

There are some more historic examples of Biotelemetry. In this web-site Swedish scientists implanted devices (through the nostrils) into patients’ brains for purported brain control. The web-site reads like the script to a bad B-movie.

A more conventional use of biotelemetry is for heart monitoring. Wireless telemetry from implanted medical devices provides obvious benefits. In the cardiology area, Transoma Medical is one example of a company that makes wireless telemetry systems for cardio monitoring.

This patent describes an implanted device which is powered by the heart tissue through piezoelectric energy converter and modulates the signal based on the activity of the heart.

Wireless Medical Telemetry Service (WMTS) operates in the 608 to 614 MHz frequency range, with other frequencies (1395 to 1400 MHz, and 1429 to 1432 MHz) set aside for general medical telemetry.

The FDA has strict guidelines on the use of WMTS which can only be administered by a licensed physician or hospital. Since WMTS shares radio spectrum space with astronomy applications, WMTS cannot be used within 80Km of an astronomy station. Due to the lack of available spectrum space, medical telemetry has made use of unused bandwidth in broadcast television, in particular, channels 7-13. With the advent of Digital TV, that spectrum is now being used by the primary user -- the TV broadcaster forcing WMTS providers to find bandwidth elsewhere in the spectrum.

Virtual instrumentation brings tools for organizing the data received from a wireless medical telemetry system. In this example researchers from Kansas State university, used LabVIEW and a MySQL database to organize the captured data from what they term a Wireless Body Area Network. (WBAN)

For a primer on WMTS, click here. For a detailed list of biotelemetry resources, Texas A&M offers a rich web site.

Best regards,
Hall T.

0 Comments:

Post a Comment

<< Home