Access Spectrum to buy Aerwv licenses, become largest 220MHz spectrum owner
, Bethesda, MD, has agreed to acquire regional and national 220MHz spectrum licenses owned by New York-based Aerwāv. An Aerwāv spokesman said that the company is retaining site-specific licenses associated with its 220MHz systems in San Francisco, Northern California, New England and the Midwest.
The jewel in the basket of 220MHz spectrum acquired by Access Spectrum is a set of frequency configurations that allows nationwide operation on 12 channels, each 12.5kHz wide.
When the transaction closes, Access Spectrum will have its first inventory of nationwide channels for leasing to service providers and end-users. In an FCC auction, Access Spectrum previously purchased 700MHz spectrum for the same purpose. Its 700MHz licenses include 746MHz-747MHz and 776-777MHz in 18 Major Economic Areas and 762MHz-764MHz and 792MHz-794MHz in 3 MEAs. (See map.) About 12% of the geographic areas covered by its licenses is encumbered by UHF-TV broadcast stations on either co-channel or adjacent channel assignments.
Valuable FCC waivers
Last year, a previous owner of some of Aerwāv’s 220MHz spectrum licenses, Securicor Wireless (a company that Aerwāv subsequently purchased, and which now is an Aerwāv subsidiary), received rule waivers from the FCC. The waivers serve to “harmonize” construction deadlines for what was a patchwork of site-specific, regional area and national footprint licenses with various build-out requirements.
Those waivers passed to Aerwāv when the FCC transferred the licenses from Securicor Wireless to Aerwāv last year, and they will pass to Access Spectrum. In January, Aerwāv added to its 220MHz spectrum inventory with the purchase of four more licenses at an FCC auction.
Through a combination of construction and acquisition, Securicor Wireless accumulated narrowband systems that use either amplitude-companded single-sideband with LTR trunking or linear modulation with a variation of MPT 1327 trunking.
Mark Crosby, president of Access Spectrum, said that Aerwāv has installed and activated enough radio repeaters to satisfy the harmonized construction deadlines. He said that after the license transfer to Access Spectrum, the company would provide Aerwāv with access to enough channels to continue operating its systems.
Securicor Wireless’ largest system serves New England and has an office in Canton, MA, near Boston. At least two former Securicor Wireless regional managers have started their own companies to operate systems licensed to Aerwāv in other regions.
12.5kHz FM possible
The FCC has dropped its insistence that 220MHz licensees use narrowband technology and 5kHz-wide channels. The agency’s policy change allows five contiguous 5kHz channels first to be “aggregated” into a 25kHz bandwidth and then to be “split” into two 12.5kHz channels.
Among its license purchases, Access Spectrum will be acquiring six such frequency configurations in a combination of regional and national licenses such that it could offer users as many as 12 nationwide 12.5kHz channels. Customers will be able to lease 220MHz spectrum from Access Spectrum by specifying a geographic footprint, spectrum quantity and channel bandwidth
That’s important, because a sacrifice of narrowband spectrum efficiency allows the use of lower-cost FM equipment, including smaller portable transceivers with longer battery life.
Moreover, Todd Ellis, operations manager for the Telecommunications Division at Booth & Associates, Raleigh, NC, explained that part of what would be lost in spectrum efficiency would be made up in the roughly 30% greater coverage delivered by 12.5kHz FM. (See “Why 220MHz?”) He pointed out that propagation prediction models that have been crosschecked with actual coverage measurements for installed systems indicated the 30% difference.
Geoff Shirley, Aerwāv’s director of engineering, said that exhaustive tests of linear modulation technology showed barely any difference between FM and linear modulation range.
Inventory for existing customers
Aerwāv’s chief executive, Robert J. Shiver, said that Aerwāv would continue to service its existing customer base. Although the company closed its Kansas City, MO, operations center last month, it maintains product inventory at a Kansas City address that has long been associated with land mobile radio—the previous Midland warehouse at 1690 N. Topping Ave. Aerwāv also keeps some product inventory in San Francisco.
Aerwāv has had a contract with Mercury Electronic Manufacturing Service in Garner, IA, for product fulfillment services. Suntron acquired Mercury on March 11, and the arrangement for fulfillment services—the manufacturing of new units and the release of inventory—appears be under review by the new owner.
With its spectrum purchase, Access Spectrum will become the nation’s largest owner of national, regional and local spectrum licenses in the 220MHz band. Rush Network, Dallas, has a five-channel national license. Sophia Communications, Burr Ridge, IL, has a 10-channel nationwide license. The National Rural Telecommunications Cooperative, Herndon, VA, has one five-channel and one 10-channel nationwide license, plus licenses for another seven nationwide channels.
The other two large band managers, Pegasus Guard Band, Bala Cynwyd, PA, and Nextel Communications, Reston, VA, have no discernible plans for making 700MHz spectrum that they purchased from the FCC at auction available for leasing.
Crosby said that buying the licenses from Aerwāv would “provide an excellent foundation for [Access Spectrum] to make selected acquisitions that further broaden our spectrum holdings,” although he may not necessarily be targeting Rush, Sophia or NRTC. Spectrum in the 216MHz–220MHz band owned by other licensees and spectrum in the 220MHz band licensed for local and regional coverage could be possible acquisition targets.
216MHz-225MHz: a fresh view
Ellis said that he expects FM will become the “mode of choice” for 220MHz, supplanting existing narrowband operations on 5kHz channels. With as many as eight companies offering FCC type-accepted FM radios for use on 12.5kHz channels in the 216MHz–220MHz band, he expects a number of them to offer 220MHz equipment. Motorola has announced its intention to do so.
Ellis said that someone eventually may petition the FCC to reallocate the 222MHz–225MHz band from amateur radio to land mobile, citing limited use by amateurs as evidenced by few product offerings for the band.
He pointed out a technical reason favoring a reallocation of 222–225MHz: pairing that spectrum with 217MHz-220MHz spectrum that the FCC has earmarked for auction. “Simple math here: 3MHz low, 3MHz high, 2MHz guard band = 120 nationwide channels for 12.5kHz-spaced land mobile users, all virgin frequencies in most areas,” Ellis said. “Finally, 220MHz is used efficiently.”
In the middle, the 220MHz-222MHz band might be subjected to an FCC spectrum audit to verify operational systems and to delete licenses for defunct systems, Ellis said. Meanwhile, existing narrowband voice and data systems and the new 12.5kHz FM systems on contiguous channels would continue operating. He said that mobile data manufacturers might push automatic vehicle location and automatic crash notification telematics equipment for this band.
“A whole new marketing push will move AVL and ACN from cellular to 220MHz,” Ellis said.
Interference potential
Jack Daniel, owner of the Jack Daniel Company in Rancho Cucamonga, CA, has been selling narrowband 220MHz radio equipment for as long as the band has been allocated for land mobile radio use. He said that mixing the 220MHz band’s current single-sideband-based technology with FM radios could spawn interference problems.
He said that the latest single-sideband radios boast a 60dB adjacent-channel rejection figure at 5kHz and suggested that they may not suffer as much co-channel interference from FM radios as the FM radios would suffer from single-sideband radios—but he added that potential interference between the two technologies has not previously been tested or studied.
“We don’t need to keep repeating the same mistake of allowing incompatible systems to occupy the same band,” Daniel said, referring to the 800MHz interference controversy involving public safety FM systems and Nextel digital systems. “The FCC may not care, but we should, if we expect our customers to have maximum value from their system investments over time.”
With respect to interference, it is apparent that there would be some challenges in consolidating the band. At least one engineering expert said that that linear modulation would have “some advantages” when sharing a wavelength with FM.
Daniel said that he hopes Access Spectrum will offer its channels to people using 5kHz-channel equipment instead of using modified FM radios that require two adjacent 5kHz channels.
