MMDS (Multichannel Multipoint Distribution
Service) - TACS
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. It is most commonly used in sparsely populated rural
areas, where laying cables is not economically viable.
The BRS band uses microwave
frequencies from 2.3 GHz 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 6
MHz "channels" (31 in USA) 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 30.34 Mbit/s with 64QAM modulation, and 42.88
Mbit/s with 256QAM modulation. Due to forward error correction and
other overhead, actual throughput is around 27 Mbit/s for 64QAM and
38 Mbit/s for 256QAM.
The newer BRS Band Plan makes changes to channel size and licensing
in order to accommodate new WIMAX TDD fixed and mobile equipment,
and reallocated frequencies from 2150–2162 MHz to the AWS band.
These changes may not be compatible with the frequencies and channel
sizes required for operating traditional MMDS or DOCSIS based
equipment.
Local Multipoint Distribution Service
(LMDS) and BRS have adapted the DOCSIS (Data Over Cable Service
Interface Specification) from the cable modem world. The version of
DOCSIS modified for wireless broadband is known as DOCSIS+.
Data-transport security is accomplished under BRS by encrypting
traffic flows between the broadband wireless modem and the WMTS
(Wireless Modem Termination System) located in the base station of
the provider's network using Triple DES.
MMDS provided significantly greater
range than LMDS.
MMDS may be obsoleted by the newer 802.16 WiMAX standard approved
since 2004.
MMDS was sometimes expanded to Multipoint Microwave Distribution
System or Multi-channel Multi-point Distribution System. All three
phrases refer to the same technology (Wiki).
About TACS
TACS
Consulting Delivers The Insight and Vision on Information
Communication and Energy Technologies for Strategic Decisions.
TACS is Pioneer and Innovator of many Communication Signal
Processors, Optical Modems, Optimum or Robust Multi-User or
Single-User MIMO Packet Radio Modems, 1G Modems, 2G Modems, 3G
Modems, 4G Modems, 5G Modems, 6G Modems, Satellite Modems, PSTN
Modems, Cable Modems, PLC Modems, IoT Modems and more..
TACS consultants conducted fundamental scientific research in
the field of communications and are the pioneer and first
inventors of PLC MODEMS, Optimum or Robust Multi-User or
Single-User MIMO fixed or mobile packet radio structures in the
world.
TACS is a leading top consultancy in the field of Information,
Communication and Energy Technologies (ICET). The heart of our
Consulting spectrum comprises strategic, organizational, and
technology-intensive tasks that arise from the use of new
information and telecommunications technologies. TACS Consulting
offers Strategic Planning, Information, Communications and
Energy Technology Standards and Architecture Assessment, Systems
Engineering, Planning, and Resource Optimization.
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TACS is a leading top consultancy in the field of information, communication
and energy technologies (ICET).
The heart of our consulting spectrum comprises strategic,
organizational, and technology-intensive tasks that arise from the use of new
information, communication and energy technologies. The major emphasis in our work is found in innovative consulting and
implementation solutions which result from the use of modern information,
communication and energy technologies.
TACS
- Delivers the insight and vision
on technology for strategic decisions
- Drives
innovations forward as part of our service offerings to customers
worldwide
- Conceives
integral solutions on the basis of our integrated business and technological
competence in the ICET sector
- Assesses technologies and standards and develops
architectures for fixed or mobile, wired or wireless communications systems
and networks
- Provides
the energy and experience of world-wide leading innovators and experts in their fields for local,
national or large-scale international projects.
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