Wireless Medical Telemetry
Wireless medical telemetry (WMT) is generally used to monitor patient’s parameters, mostly physiological parameters like heart rate, rhythm, over a distance via transmitting radio-frequency (RF) between a transmitter located in the patient’s body and a central monitoring station. These devices are very helpful and have the advantage of allowing patient movement and participate most normal activity since patient is not in the bed any more.
The Wireless Medical Telemetry Service (WMTS) report and order sets aside the frequencies of: 608 to 614 MHz, 1395 to 1400 MHz, and 1429 to 1432 MHz for primary or co-primary use by eligible wireless medical telemetry users. This action creates frequencies where medical telemetry will enjoy protection against interference from other in-band RF sources. This is very important for these WMT devices, since interferences can be lethal. A key feature of the new WMTS is the provision for establishment of a Frequency Coordinator to maintain a database of user and equipment information to facilitate sharing of the spectrum and to help prevent interference among users of the WMTS. The FCC order also provides a definition for wireless medical telemetry, which is consistent with recommendations made in April 1999 by the American Hospital Association (AHA) Task Group on Wireless Medical Telemetry. Define of wireless medical telemetry is ‘the measurement and recording of physiological parameters and other patient-related information via radiated bi- or unidirectional electromagnetic signals”