Location Service Deployment May Constrain 902-928 MHz Amateur Use
Jun 11, 2013 — A portion of the 902-928 MHz (33 centimeter) band may become less useful to radio amateurs in urban areas as a result of an FCC Order. The FCC has given Progeny LMS, LLC consent to begin commercial operation of its multilateration location and monitoring service (M-LMS) in the upper portion of the band. According to the FCC, Progeny’s location service is designed to operate on approximately 4 megahertz — about one-half of the M-LMS portions of the band between 919.750 and 927.750 MHz — where Progeny holds licenses.
“Progeny is deploying a wide-area positioning system to provide more precise location services in areas where Global Positioning System (GPS) and other existing services may not work effectively, particularly indoors and in urban canyons,” the FCC said in its Order, released June 6.
The FCC opened the 33 centimeter band to hams on a secondary basis (Amateur Radio is secondary on all bands above 420 MHz) in 1985, provided hams did not interfere with the automatic vehicle monitoring (AVM) service, which the Commission subsequently expanded into the M-LMS. While M-LMS operations, at least on paper, have a higher priority than unlicensed Part 15 devices on the band, Progeny had to demonstrate through field testing that its network would not cause “unacceptable levels of interference” to such Part 15 devices as cordless telephones and baby monitors. This was a result of an FCC policy to promote “co-existence” in the band, while not elevating Part 15 devices to co-equal status with M-LMS systems.
“Instead, the Commission sought to balance the equities and value of each use without undermining the established relationship between unlicensed operations and licensed services,” the FCC said in its Order. The FCC asserted that Part 15 devices “will adapt to Progeny’s operations because they are designed for operation in an interference environment.”
In his June 2012 “It Seems to Us…” editorial in QST, ARRL CEO David Sumner, K1ZZ, pointed out that effectively setting unlicensed services such as Part 15 at a higher priority than licensed services “is the reverse of the usual situation in which Part 15 devices are at the bottom of the pecking order.” Federal (military) radiolocation and ISM Part 18 devices are at the top of the 902-928 MHz food chain. Sumner predicted in his editorial that operations such as Progeny’s “will pose some new challenges for amateurs in a band that is already impacted by other users.” On the other hand, he said, sharing bands with the military has helped Amateur Radio to stave off spectrum grabs from commercial interests. The ARRL did not file comments in this proceeding because, as Sumner explained, M-LMS “was already allocated with a higher priority.”