The
local multipoint distribution service (LMDS) and multichannel multipoint distribution
service (MMDS) have their historical
roots in television. MMDS's pre-cursor, the multipoint distribution service
(MDS), was established by the Federal Communications Commission (FCC) in 1972.
The Commission originally thought MDS would be used primarily to transmit business
data. However, the service became increasingly popular for transmitting
entertainment programming. Unlike conventional broadcast stations, whose
transmissions are received universally, MDS programming is designed to reach
only a subscriber-based audience.
LMDS is a fixed broadband line-of-sight,
point-to-multipoint, microwave system, which operates at a high frequency
(typically within specified bands in the 24-40GHz range) and can deliver at a
very high capacity, depending on the associated technologies. Given the
complexity of the equipment required (and the power needed to deliver signals)
both of these technologies are regarded as prohibitively expensive for the
consumer market. Therefore, LMDS operators will initially be targeting
enterprises and network operators, although the consumer market is likely to
emerge over time as the cost of CPE comes down (partly driven by the take-up of
IP). It should be noted that CPE costs $5,000 for LMDS in the 26GHz range.
MMDS allows two-way voice, data and video
streaming. It operates at a lower frequency than LMDS (typically within
specified bands in the 2-10GHz range) and therefore has a greater range and
requires a less powerful signal than LMDS. MMDS is a less complicated, cheaper
system to implement. As a consequence, the CPE is cheaper, thus it has a wider
potential addressable market. It is also less vulnerable to rain fade - the
interference caused by adverse weather conditions that can undermine the
quality of the microwave signal. However, the bandwidth offered by LMDS makes
this the more viable option.
BENEFITS
Wireless systems are being deployed to fulfil a number of
functions. On a network level they are suitable for both access and backbone
infrastructure. It is generally agreed, however, that it is in the access
market where the key advantages are held over wireline alternatives. The
principal strengths of LMDS/MMDS are:
- Speed of network deployment is
much quicker with wireless systems enabling rapid, early market entry
- Entry, deployment and upgrading
costs are much lower than for wireline alternatives, for which engineering
(cabling and trenching) costs are significantly higher
- The maintenance, management and
operation expenditure is lower. Wireless systems can be rolled out much
faster, enabling an earlier return on investment
- Scalable architectures enable
expanded coverage and services in direct relation to the level of demand
- Only one network architecture
is required to provide a full suite of interactive voice, video and data
services that can be expanded as and when desired
With this fixed wireless broadband technologies, wimax came to provide a wireless network with the speed, capacity, and reliability of a hardwired network, while maintaining with the flexibility, simplicity, and low costs. Creadits to the innovators! =D
TumugonBurahinWireless systems are being deployed to fulfil a number of functions. On a network level they are suitable for both access and backbone infrastructure.
TumugonBurahinMMDS signals can travel longer distances Provide service to an entire area with only a few radio transmitters. MMDS cell size can have a radius of up to 35 miles (56 kilometers) while the LMDS Can transmit from 51 to 155 Mbps downstream and 1.54 Mbps upstream Over a distance of up to about 5 miles (8 kilometers). And MMDS services have been around for 20 years, there is a wealth of experience--at least in respect to the one-way distribution technology.
TumugonBurahinMMDS can travel longer distance than LMDS...these two technologies made a mark for business entities on improving their communication systems.
TumugonBurahin