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2011年7月30日星期六
IEEE, white, space, WRAN, standard, radio, cellular, broadband IEEE publishes 'white space' WRAN standard
LONDON – The Institute of Electrical and Electronics Engineers (IEEE) has published the 802.22 standard for Wireless Regional Area Networks (WRANs). The standard covers broadband wireless access at up to 22-Mbps per channel over distances up to 100 kilometers from a transmitter without interfering with terrestrial television broadcasts that use the same part of the spectrum.
The standard covers much the same ground as the Weightless standard being developed by Neul Ltd. (Cambridge, England) in that it is intended to provide a framework for "white space" reuse of UHF and VHF spectrum.
However, while Neul's Weightless standard is intended to open up access for relatively small data payloads that are part of an internet-of-things IEEE 802.22 is trying to provide secure high-speed broadband communications that are not served by other forms of wired and wireless communications.
Under 802.22 each WRAN will deliver up to 22 Mbps per channel without interfering with reception of existing TV broadcast stations, using the so-called white spaces between the occupied TV channels. The technology is useful for serving less densely populated areas, such as rural areas, and developing countries, the IEEE (Piscataway, New Jersey) said.
As well as channel specifications, 802.22 covers the required cognitive radio capabilities including dynamic spectrum access, incumbent database access, accurate geo-location techniques, spectrum sensing, spectrum etiquette, and coexistence for optimal use of the available spectrum.
Related links and articles:
http://www.ieee802.org/
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IEEE, white, space, WRAN, standard, radio, cellular, broadband IEEE publishes 'white space' WRAN standard