WASHINGTON-The wireless telecommunications industry may have to tap into federal government and broadcast spectrum, implement new technologies and share more to meet operational requirements in the future, says a new government study.
The report by the National Telecommunications and Information Administration is part of a long-range spectrum planning effort required by Congress to identify spectrum requirements, develop spectrum availability and planning options and craft spectrum allocation implementation plans.
“Long-range spectrum [planning] is critical to the effective management of the radio spectrum,” said NTIA.
NTIA explained that identifying available spectrum early aids the development of new telecommunications services and gives equipment manufacturers sufficient lead time to design and build radios.
NTIA, a unit of the Commerce Department that advises the president on telecommunications policy and manages federal government spectrum, said 119 megahertz below the 5 GHz band is required over the next 10 years for mobile communications.
NTIA believes 50 megahertz of that total should be earmarked for public safety and industrial radio services, yet none of 235 megahertz reallocated from the federal government to the Federal Communications Commission has been designated for any private wireless service. Another 45 megahertz recently was transferred to the private sector, but the FCC has not decided how to divvy it up.
Additional spectrum (72 megahertz) could come from the broadcasting industry as TV licensees move off the VHF band and switch to digital systems on the UHF band. Broadcasters will have two TV channels (six megahertz each) during a 15-year transition from analog to digital technology.
Aside from new spectrum allocations, NTIA suggested four options for accessing spectrum in coming years.
The first calls for making more efficient use of current frequencies through new digital technologies, including Time Division Multiple Access and Code Division Multiple Access, narrowbanding, antenna sectorization and automated frequency selection.
Digital technology is being phased into the wireless telephony and dispatch radio industries, while private two-way radio systems are preparing to move to more narrow channels.
Sharing is cited as another way of using spectrum more wisely. NTIA notes that UHF-TV channel 16 has been made available for public-safety communications in New York City. Sharing VHF maritime mobile channels with land mobile users is another example of the technique.
Sharing and implementing new technologies in public-safety communications, according to NTIA, could also satisfy some of that sector’s spectrum requirements.
A second option involves relocating existing spectrum users to other frequencies, a scheme in use today whereby personal communications services carriers pay fixed microwave users to move from the 2 GHz band.
A third option is for wireless systems lacking mobile functions, such as long-haul microwave systems, to convert to non-spectrum alternatives, like fiber optic cable.
The fourth option, which also has limited applicability for mobile communications, recommends the use of higher frequencies above 20 GHz. This option is more practical for the intelligent transportation system, wide-band video and other fixed applications than for mobile communications because of propagation limitations in the higher frequencies.
