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802.11/WLAN/Wi-Fi/WiGig
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Wireless LANS utilize various channels in the 2.4, 5, and 6 GHz bands (multiple countries), and (in theory) the 3.6 GHz band (U.S. only). For a list of which channels are available in which regions, refer to the Wikipedia article.
Wi-Fi is a trademark permitted for devices that are based upon a published standard of the IEEE 802.11 committee and that have been certified by the Wi-Fi Alliance. Wi-Fi is presently incorporated in about three billion devices. Wireless cash registers were one of the earliest applications of what is now Wi-Fi.
Wi-Fi devices operate on an unlicensed basis, generally meaning they cannot cause interference to licensed services, and must accept any interference caused to them. Wi-Fi shares bands with other unlicensed or ISM devices, such as cordless phones at 2.4 and 5.8 GHz and microwave ovens at 2.4 GHz.
Some of the key patents related to Wi-Fi are credited (in the courts at least) to the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia, which has collected over $400 million in royalties and legal settlements over patent rights.
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Frequency Bands |
Band | Use | Service | Table |
2400 - 2495 MHz | Wireless LANs | - | - |
3655 - 3700 MHz | Wireless LANS (U.S. only; standardized but not used) | - | - |
4910 - 4990 MHz | Wireless LANs (Japan) (U.S. public safety 4940-4990) | - | - |
5030 - 5090 MHz | WLANs (Japan, 2002-2017) | - | - |
5150 - 5350 MHz | Wireless LANs (U-NII-1 and U-NII-2A) | - | - |
5470 - 5895 MHz | Wireless LANs (U-NII-2C, U-NII-3, U-NII-4) | - | - |
5925 - 7125 MHz | Wireless LANs (U-NII-5, U-NII-6, U-NII-7, U-NII-8) | - | - |
42.39 - 46.71 GHz | Wireless LANs (WiGig) | - | - |
57.24 - 74.52 GHz | Wireless LANs (WiGig) | - | - |
External Links:
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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:
![](Graphics/7e806835-6bda-49ce-8b62-0d9631fda4be.png) 802.15.4 HRP UWB PHY band allocation
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Radio Astronomy Formaldehyde (H2CO) Observations
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Radio astronomers observe molecular lines of formaldehyde at both 14.49 GHz and 4830 MHz. According to the European Science Foundation's Committee on Radio Astronomy Frequencies (CRAF):
At 14.4885 GHz an important formaldehyde (H2CO) line exists, which has been observed in the direction of many galactic sources. Since these lines originate from the upper levels of ortho-formaldehyde their study gives valuable information on the physical conditions of the interstellar medium, because the excitation energies required to produce such lines are different from the energies required to produce the H2CO lines observed at 4829.66 MHz.
There is no formal allocation to the radio astronomy service in these bands, but the international footnote 5.149 and the U.S. footnote US203 note that consideration should be taken to the use of 14.47-14.5 GHz and 4825-4835 MHz band segments for radio astronomy.
In the U.S., there is an increasing use of the entire 14-14.5 GHz band by vehicle-, ship-, and airplane-based Internet terminals that communicate through geostationary satellites (14-14.5 GHz is used as the uplink band). Such activities are required by the FCC to be coordinated with the radio astronomy service.
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Frequency Bands |
Band | Use | Service | Table |
4825 - 4835 MHz | Radio astronomy observations of formaldehyde (4829.66 MHz) | Radio Astronomy | - |
14.47 - 14.5 GHz | Radio astronomy observations of formaldehyde (14.4885 GHz) | Radio Astronomy | - |
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