|Federal Communications Commission|
Certain kinds of medical telemetry devices are permitted to use portions of the spectrum also used for TV broadcasting. This fact sheet provides information on how users of medical telemetry devices can avoid interference from TV broadcasting as local TV stations begin the transition to digital transmission.
Medical telemetry devices operate on a secondary basis to TV broadcasting, that is, they must tolerate any interference that may be caused by local television stations' broadcast signals. Users and manufacturers of medical telemetry devices have generally been able to avoid interference by using TV channels that are vacant locally. In other words, the medical devices use frequencies that local TV stations do not.
At the direction of Congress, the FCC has provided for the introduction of digital television (DTV) stations in the TV band. In order to accomplish this, the FCC has provided each local TV station with an additional channel that will be used to broadcast digital TV during the transition. This means there are fewer vacant channels in every market, and that in some local areas, channels that were once unused for TV broadcasting may now be used for DTV.
In those areas where DTV will use frequencies now occupied by medical devices, users should adjust their devices so that they continue to operate on those TV channels that are vacant in their area. Once the DTV transition is complete, no further changes should be necessary.
Q. What are medical telemetry devices?
A. Hospitals and other health care facilities use medical telemetry devices monitor patients' vital signs and other important parameters and transmit this information via radio to a remote location such as a nurses' station. For example, wireless cardiac monitors are often used to monitor patients following surgery. Certain types of medical telemetry devices may be used in the home.
Q. How can DTV stations interfere with medical telemetry devices?
A. The FCC has developed a plan where each existing analog TV station is assigned a vacant TV channel to use for digital television service. In some areas of the country, this new DTV assignment may be on a formerly vacant channel that a telemetry device user had chosen for its operations. If the medical telemetry device user continues to operate on this channel, it can receive interference from new DTV transmissions on the same channel.
Q. Will this be a widespread problem?
A. Until recently, medical telemetry devices were only permitted to operate on TV channels 7 - 13. The vast majority of new DTV stations will operate on UHF channels 14 - 51. Of the 24 DTV stations that are scheduled to go on the air by November 1, 1998, only two will use vacant TV channels between 7 and 13.
Q. What can be done if interference does occur?
A. Late last year the FCC made nearly all of the TV spectrum available for medical telemetry devices. Analyses showed that vacant TV channels will be available for medical telemetry devices throughout the DTV transition. In most cases, existing medical telemetry devices can be retuned to operate on a different vacant TV channel. In some cases, current equipment may not have adequate tuning range to move to a vacant channel and may need to be replaced.
Q. What is the FCC doing to educate the industry and the public about this issue?
A. Interference can be avoided by appropriate planning and exchange of information. The FCC has taken a number of steps to facilitate this process. At the FCC's request, broadcast industry representatives have asked TV stations to contact local health care facilities and inform them of their plans to initiate DTV service. The Commission will also request information from broadcasters to ensure that they have coordinated with health care facilities before beginning their DTV operation.
The FCC has also contacted the manufacturers of medical telemetry devices to ask that they alert existing users of their equipment about potential interference from new DTV operations. The FCC is working with FDA to disseminate appropriate information to the health care industry.
Q: What should medical telemetry device users do about this?
A: The Commission has previously alerted the manufacturers, installers and users of medical devices through the October 20, 1997 Report and Order, published in the Federal Register at 62 FR 58656, October 30, 1997, that they may need to take action to avoid interference to their operations during the transition to DTV service.
Specifically, they need to learn what DTV channels are being assigned in their market so they can continue to pick a vacant channel for their transmissions. If a medical telemetry device is using a television channel that will not be used for DTV, no further action should be required. If, however, a medical telemetry device is using a television channel that has been assigned for DTV, the user will need to work with their manufacturer and switch to a channel that will not be used for DTV in their area. In those limited instances in which a user has equipment that cannot be retuned, new devices would have to be obtained to ensure interference-free operation.
Q: Where can telemetry device users find out what DTV channels have been assigned in their market so they can avoid interference?
A: Users can call each television station in their market to learn what channels each station will use for digital television service. Alternatively, the information for every market is listed on the FCC's Internet Website at http://www.fcc.gov/healthnet/.