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Concept
Bande L (radio)
Résumé
The L band is the Institute of Electrical and Electronics Engineers (IEEE) designation for the range of frequencies in the radio spectrum from 1 to 2 gigahertz (GHz). This is at the top end of the ultra high frequency (UHF) band, at the lower end of the microwave range.
In Europe, the Electronic Communications Committee (ECC) of the European Conference of Postal and Telecommunications Administrations (CEPT) has harmonized part of the L band (1452–1492 MHz), allowing individual countries to adopt this spectrum for terrestrial mobile/fixed communications networks supplemental downlink (MFCN SDL). By means of carrier aggregation, an LTE-Advanced or UMTS/HSDPA base station could use this spectrum to provide additional bandwidth for communications from the base station to the mobile device; i.e., in the downlink direction.
In the Americas, mobile services are operated between the 1.7 GHz to 2.1 GHz range in the PCS and AWS bands.
Satellite navigation
The Global Positioning System carriers are in the L band, centered at 1176.45 MHz (L5), 1227.60 MHz (L2), 1381.05 MHz (L3), and 1575.42 MHz (L1) frequencies. L band waves are used for GPS units because they are able to penetrate clouds, fog, rain, storms, and vegetation. Only dense environments such as heavy forest canopies or concrete buildings can cause GPS units to receive data inaccurately.
The Galileo Navigation System, the GLONASS System, and the BeiDou systems use the L band similar to GPS, although the frequency ranges are named differently. Modern receivers, such as those found in smartphones, are able to take advantage of multiple systems (usually only around the oldest L1 band) at the same time.
Mobile phones operate at 600–900 and 1700–2100 MHz. Iridium Communications satellite phones use frequencies between 1616 and 1626.5 MHz to communicate with the satellites. Iridium Communications 2-way messaging service Snapdragon Satellite will utilize frequencies in the L Band as well. Inmarsat and Ligado Networks (formerly LightSquared) terminals use frequencies between 1525 and 1646.
Source officielle
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