The FCC adopted a waiver March 10 to an Order in ET Docket No. 04-352 permitting radiated emissions from ultra-wideband (UWB) transmitters to be measured while the transmitter is in its normal operating mode.
The waiver is intended to provide greater flexibility and innovation in designing UWB devices.
The commission previously established regulations permitting the marketing and operation of products incorporating UWB technology. UWB devices operate on the same frequency bands used by licensed stations. Thus, the commission established what it considered to be a conservative procedure to measure the levels of radio frequency emissions generated by those devices.
UWB transmitters that employ frequency hopping techniques must be measured with the hop stopped and the transmitter operating in a continuous mode; UWB transmitters that gate the emissions on and off must be measured with the emissions gated on. These procedures can result in measured emission levels that are greater than the UWB signal levels under actual operation, according to the commission.
The commission’s order last week provides a waiver of the existing measurement procedure, permitting emissions from UWB transmitters to be determined with the transmitter operating normally. The commission concluded that this would not result in increased harmful interference to licensed radio operations.
The waiver applies only to indoor or handheld UWB devices. UWB devices using this waiver may not operate within the 5030-5650MHz band. A decision to permit this waiver to apply to UWB devices that operate within the 5030-5650MHz band will be made upon the completion of the interference investigation being performed by the Institute for Telecommunication Sciences.
The waiver will remain in effect until the commission finalizes a rule making proceeding dealing with these measurement issues.
For more information, visit www.fcc.gov.