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History of the Beep
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Cleveland electronics engineer Al Gross invented radio paging in the early 1950s. Gross was a pioneer in portable VHF-UHF devices and an early proponent of “citizens radio,” now called “personal radio” (see 462.5375—462.7375 MHz). He provided paging systems for use in hospitals, though doctors initially resisted the technology.
The basic paging receiver beeps when it receives a distinctive code from a transmitter controlled by a “paging terminal,” connected to the public telephone network. Today’s more sophisticated pagers display the telephone number of the calling party, or alphanumeric messages. The World Wide Web is now the principal data input medium for alphanumeric paging.
Pagers often are used to signal waiting voice mail messages and are increasingly connected to electronic mail services. Voice paging declined in the 1980s, but was supposed to resurge with the advent of digital voice storage in the pager. Considerable investment was made in voice paging in the Narrowband Personal Communications Service (see 901—902 MHz). The reinstituted voice paging services failed to attract enough subscribers, however.
Delighting Guests
Paging also is used to control industrial equipment, to summon animals to feeding, and—in perhaps the most entertaining use we have discovered—to activate fireworks contained in banquet floral decorations.
Today most paging is provided by FCC licensees on a commercial basis. Traditionally, the two types of for-profit paging companies were designated radio common carriers (RCCs), which enjoyed interference-protected service areas and, in some cases, were required to have state utility certification; and Private Carrier Paging (PCP) providers, who operate on channels shared with other such carriers and are supposed to be exempt from state regulation.
Federal budget legislation in 1993 requires similar or comparable treatment, or “regulatory symmetry,” for substantially similar Commercial Mobile Radio Services (CMRS).
CMRS describes radio services offered to the public, or a large segment of the public, for profit and which interconnect to the public telephone network. Many types of CMRS services exist. PCP services were classified as CMRS in 1996. “There are no longer any real differences between private carrier and common carrier paging systems,” according to the FCC.
Nevertheless, the former system continues in that separate regulations govern RCC-based paging in FCC Part 22 rules and PCP-based paging in Part 90. “Not all substantially similar services must have identical technical and operational rules,” the FCC said.
Major Changes
Paging licenses were traditionally granted on a first-come, first-serve basis using careful frequency coordination to avoid interference between systems. The FCC is introducing a new regime into CMRS paging: license auctions in specified geographic areas. Incumbent licensees will retain certain interference protections.
"We noted that if an incumbent already has a significant presence in a geographic area, other potential applicants may choose not to bid for that geographic area," the FCC said. "Thus, market forces, not regulation, would determine participation in competitive bidding for geographic area licenses.
"…Even where only 30 percent of a geographic area is available to a potential new entrant, we do not believe that it has been shown that the new entrant cannot establish a viable system that serves the public as well as the incumbent." The Commission dismissed all mutually exclusive applications for paging licenses filed after July 31, 1996, in preparation for the auction regime (Docket WT 96-18).
In the 929—930 MHz and 931—932 MHz bands, the FCC established paging licenses in Major Economic Areas (MEAs) developed by the Commerce Department and composed of Economic Areas (EAs, see the following).
Special exemptions from auctions apply to certain established paging licensees in the 929—930 MHz and 931—932 MHz bands who earned exclusive licenses through extensive network construction under earlier regulations.
In other, older paging bands, such as 35—36 MHz, 43—44 MHz, 152—159 MHz, and 454—460 MHz, containing small- and medium-sized paging systems, the FCC adopted Economic Areas (EAs), each consisting of metropolitan or similar areas that are centers of economic activity, with surrounding economically related counties.
As is the case with most auctioned licenses, each geographic area licensee is required to provide coverage to specified portions of the population by a certain date. Alternatively, the licensee may demonstrate that it provides "substantial service," that is, "service that is sound, favorable, and substantially above a level of mediocre service." Failure to meet these requirements is supposed to automatically terminate the license.
Incumbents (who did not obtain their licenses in auctions) may make certain changes to their operations, including adding or modifying their transmission sites. To expand their existing radio contours, they must obtain the consent of the geographic licensee for the expansion area, or buy the expansion area at auction even if the area is larger than needed. If the incumbent stops operating, the FCC performs "spectrum reversion," turning the incumbent’s spectrum over to the geographic licensee for that area.
Other services use the 152—159 MHz and 454—460 MHz bands allocated to paging services. These include the Basic Exchange Telecommunications Radio Service (BETRS), which provides rural subscribers with phone service; and pre-cellular two-way mobile telephone services, which operate mostly in the western U.S.
BETRS is licensed under the Rural Radiotelephone Service. Only local exchange telephone companies or companies having state approval to provide local phone service may provide BETRS. By definition, BETRS is a fixed service and is not CMRS.
The Commission decided to include both BETRS and the two-way mobile telephone services on paging channels in its auction scheme, over the protests of rural telephone advocates. However, it will still allow providers to obtain licenses for these services on a secondary, non-interference basis to geographic-area paging licensees.
(Original entry based upon "Wireless Spectrum Finder" by Benn Kobb. Wireless Spectrum Finder is now (c)MMX Technology LLC.)
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Frequency Bands |
| Band | Use | Service | Table |
| 35 - 36 MHz | Paging (portions of band) | Land Mobile | N |
| 43 - 44 MHz | Paging (portions of band) | Land Mobile | N |
| 152 - 159 MHz | Paging (portions of band) | Land Mobile | N |
| 454 - 460 MHz | Paging (portions of band) | Land Mobile | N |
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IEEE 802.15.4 HRP UWB
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High pulse repetition frequency ultra-wideband (HPR UWB) is one of the physical layers defined for low data rate personal area network (LR-WPAN) communications in the IEEE 802.15.4 standard.
According to the FiRa Consortium:
"In challenging environments, such as parking structures, hospitals, airports and high density venues, ultra-wideband (UWB) technology outperforms other technologies in terms of accuracy, power consumption, robustness in wireless connectivity, and security, by a wide margin.
"UWB securely determines the relative position of peer devices with a very high degree of accuracy and can operate with line of sight at up to 200 meters. In contrast to narrow band wireless technologies, the use of wide bandwidth means UWB provides very stable connectivity, with little to no interference and offers highly precise positioning, even in congested multi-path signal environments.
"By calculating precise location, fine ranging based on UWB is a more secure approach to closing and opening locks, whether those locks are installed on a car door, a warehouse entryway, a conference room, or your front door."
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Frequencies |
| Frequency | Bandwidth | Use | Service | Table |
| 499.2 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 0 | - | - |
| 3494.4 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 1 | - | - |
| 3993.6 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 2 | - | - |
| 3993.6 MHz | 1.3312 GHz | 802.15.4 HRP UWB Channel 4 | - | - |
| 4492.8 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 3 | - | - |
| 6489.6 MHz | 1.0816 GHz | 802.15.4 HRP UWB Channel 7 | - | - |
| 6489.6 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 5 | - | - |
| 6988.8 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 6 | - | - |
| 7488 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 8 | - | - |
| 7987.2 MHz | 1.3312 GHz | 802.15.4 HRP UWB Channel 11 | - | - |
| 7987.2 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 9 | - | - |
| 8486.4 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 10 | - | - |
| 8985.6 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 12 | - | - |
| 9484.8 MHz | 1.35497 GHz | 802.15.4 HRP UWB Channel 15 | - | - |
| 9484.8 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 13 | - | - |
| 9984 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 14 | - | - |
External Links:
Associated Files:
802.15.4 HRP UWB PHY band allocation
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PAVE PAWS
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PAVE PAWS is a high-power phased array radar operated by the U.S. military to detect intercontinental ballistic missiles. There are presently (2013) three operating PAVE PAWS sites at Clear, AK, Cape Cod, MA, and Beale AFB, CA. The PAVE PAWS radar is also known by its government designator, AN/FPS-115.
According to the spec sheet at the fas.org Web site, PAVE PAWS has a peak/average transmit power of 582/146 kW, antenna gain of 38 dBi, and an operational range of 3,000 nm (about 5500 km).
PAVE PAWS radars are also capable of detecting echoes off of Earth-orbiting space debris.
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Frequency Bands |
| Band | Use | Service | Table |
| 420 - 450 MHz | PAVE PAWS radar | Radiolocation | F |
External Links:
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