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Feature Article*
Scalable Wireless Coverage Solutions
Contributed by LGP Allgon
As the use of
wireless devices proliferates in society, the lack of seamless coverage
has become a growing issue not only for end-users, but also for the
wireless carriers and the administrators of the environments that
prohibit wireless use. Building owners and property managers are among
those caught in the middle of this issue because they control many of
the spaces that interfere with wireless signals, leaving pockets of
unserviced airspace and lots of unhappy wireless customers. This is an
issue that should be seriously reviewed today, if wireless is to become
the communications method of choice now and in the future. This week’s
Feature Article provides an overview of what criteria should be
considered when selecting an in-building wireless coverage solution that
will support continued increases in wireless usage as well as future
generations of wireless technologies.
I.
Active vs. Passive Systems
When choosing a wireless coverage system, it is important to understand
the difference between “active” and “passive” systems. Active systems
contain active electronic components to transmit and improve signal
quality throughout the infrastructure and therefore require access to
multiple sources of electrical power. Passive systems, such as
cable-based solutions, utilize no active components and require
virtually no power other than at the main transmission source. A
“hybrid” solution utilizes features of both an active and passive model.
An
active wireless coverage system offers carriers flexible solutions that
dynamically allocate capacity to where it is needed at any time, making
the full system capacity available throughout the building. Using
fiber-optic, radio frequency (RF), or hybrid solutions, an active system
can be designed to accommodate average peak traffic load, which allows
for efficient spectrum reuse and trunking efficiency gains. While
active systems offer high-quality, efficient transmission of signals,
they also require access to multiple sources of power
throughout the building.
In
comparison, passive systems typically utilize a coax cable distribution
system with no active electronic components other than the main
transmission source. As a result, some passive systems may suffer a loss
of performance, both as a result of increased noise figures and lower
radiated power. Such losses reduce overall radio quality needed to
maintain high data rates -
a requirement that is becoming more and more important. Today, wireless
access to the Internet, such as “WiFi”, and various technologies in the
PCS band are capable of providing higher data rates, and in-building
systems must be designed to adequately and efficiently support
transmission of these frequencies. When considering a solution for
commercial office buildings, keep in mind that some passive solutions
may not provide an efficient transfer of RF from the transmission
source. For example, a single 300–foot cable run can reduce power to as
much as 10-20 times less than the introduced signal. In order to serve
multiple floors in a building, these losses could result in radiated
power at the furthest points of the network that is a fraction of the
introduced power – which may not adequately service the building.
In addition, some passive cable systems may limit the range or services
a carrier may provide on a system.
II.
Benefits of a Multi-Technology System
It is also important to ensure
that an in-building coverage system supports a full range of wireless
technologies. If the tenants’ demand for cellular coverage is satisfied but
the system capabilities are limited in terms of supporting multiple
technologies, in the long run, the goal of
ubiquitous wireless coverage is not achieved. Comprehensive wireless
systems should support a full spectrum of wireless technologies, from
emergency communications channels to cellular, PCS, paging, and 2-way
radios, to wireless Internet, UHF and VHF -- as well as future
technologies still in development.
III.
Providing the Right Solution for Multiple Wireless Operators
It is important to select an in-building system that will meet the
technical needs and approval of major wireless operators, without
interference from other operators or other technologies that may utilize
the in-building network. A single-operator solution is limited in its
ability to support multiple wireless technologies and would require
independent installations of multiple systems to support more than one
wireless carrier. Multi-operator systems allow the operators to use the
same distribution system and antenna system but maintain their own
transmission equipment and remote hub units. Although the different
operators share the system infrastructure, each operator is limited to
only access their own equipment for operation and maintenance through a
remote, dedicated server, guaranteeing the highest grade of integrity
for each operator. Further, since there is no need for individual
coverage solutions for each operator and/or system standard, there are
no additional installations or increased costs, which provides a
cost-effective solution for the property.
Here are several benefits of multi-operator systems:
-
Superior RF performance through remote hubs, with higher effective
radiated power;
-
High dynamic range, supporting long fiber runs and high number of
carriers over a common fiber infrastructure that can support
campus-type environments;
-
“Future-proof” design with a common broadband backbone, as well as
regular interfacing with international wireless standardization
committees;
-
Minimum aesthetic impact by limiting the number of antennas per node;
-
Effective and flexible operations and management through a
standardized software platform.
In
a multi-technology system, a solution with base station hotel(s), a
common fiber-optic network, a number of remote hub groups, and a common
passive multi-band antenna system will meet the objectives for a
cost-efficient, high-quality system that combines the requirements from
each individual carrier with the requirements from the property owner.
IV.
Maintenance of the In-Building System
Once an in-building coverage
system is installed, who is responsible for maintaining it? Ideally, in
addition to engineering, planning, deployment and system optimization,
the provider of any in-building wireless coverage system should assume
responsibility for the day-to-day operation, management and support of
the system. The company you select for installation of an in-building
wireless coverage solution should provide adequate engineering resources
to perform ongoing optimization, operations, maintenance and repair of
critical network elements, including antennas and base station
equipment.
Summary
In summary, when selecting an in-building
wireless coverage solution for your property and your tenants, make sure
you do your homework. It is important to understand the features of
different types of system models, the spatial and electrical
requirements of each, and the resulting consequences in terms of
transmission quality and performance. Consider the benefits of
multi-operator, multi-technology systems vs. single carrier solutions,
including installation of one common infrastructure and future-proof
design. And finally, be sure to select a provider with a proven
in-building coverage solution, engineering and maintenance support, a
successful track record, viable case studies, and a sound business
model.
LGP Allgon
provides
solutions for in-building applications, ranging from office buildings and
convention centers to storefronts, airports, casinos and complete
corporate campuses. Taking it a step further, LGP Allgon has also
successfully deployed outdoor distributed antenna systems in subways,
canyons and waterways worldwide. To view a complete portfolio of work and
to get more information about LGP Allgon Coverage Systems, please visit
http://www.us.allgon.com/coverage_engineering.htm or call Tormod Larsen at 817-684-4788.
*CRE Partners is
not responsible for the content, validity, technical accuracy or other
claims or information contained in this article. Feature Articles
are often authored by outside sources and do not necessarily reflect the
views or opinions of CRE Partners. Further, publication of
articles in the CRE Partners Newsletter and/or web site is not meant to
represent, promote, or endorse any company, brand, product or solution.
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