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Concept
Multichannel Multipoint Distribution Service
Résumé
Multichannel multipoint distribution service (MMDS), formerly known as broadband radio service (BRS) and also known as wireless cable, is a wireless telecommunications technology, used for general-purpose broadband networking or, more commonly, as an alternative method of cable television programming reception.
MMDS is used in Australia, Barbados, Belarus, Bolivia, Brazil, Cambodia, Canada, Czech Republic, Dominican Republic, Iceland, India, Kazakhstan, Kyrgyzstan, Lebanon, Mexico, Nepal, Nigeria, Pakistan, Panama, Portugal (including Madeira), Russia, Slovakia, Sri Lanka, Sudan, Thailand, Ukraine, United States, Uruguay and Vietnam. It is most commonly used in sparsely populated rural areas, where laying cables is not economically viable, although some companies have also offered MMDS services in urban areas, most notably in Ireland, until they were phased out in 2016.
The BRS band uses microwave frequencies from 2.3 to 2.5 GHz. Reception of BRS-delivered television and data signals is done with a rooftop microwave antenna. The antenna is attached to a down-converter or transceiver to receive and transmit the microwave signal and convert them to frequencies compatible with standard TV tuners (much like on satellite dishes where the signals are converted down to frequencies more compatible with standard TV coaxial cabling), some antennas use an integrated down-converter or transceiver. Digital TV channels can then be decoded with a standard cable set-top box or directly for TVs with integrated digital tuners. Internet data can be received with a standard DOCSIS cable modem connected to the same antenna and transceiver.
The MMDS band is separated into 33 (31 in USA) 6 MHz "channels", which may be licensed to cable companies offering service in different areas of a country. The concept was to allow entities to own several channels and multiplex several television, radio, and later Internet data onto each channel using digital technology. Just like with digital cable channels, each channel is capable of 30.
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