Distributed Antenna System

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Distributed Antenna System

• Max Gaebler
• Richard Elliott
• Chris Rufa

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Introduction

• What is a Distributed Antenna System
• How does it work?
• Why should you care?
• Business Applications of DAS
• Benefits of using Distributed Antenna System
• Potential downfalls of a DAS system
• Conclusion

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DAS Overview

• What is DAS?
• How does it work?
• Why should you care about DAS?

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What is DAS?

• According to Wikipedia
• DAS is a network of spatially separated antenna
  nodes connected to a common source via a
  transport medium that provides wireless service
  within a geographic area or structure.
• DAS can connect to a variety of wireless
  devices and services and then rebroadcasts those
  signals throughout areas in which DAS is
  installed.
• DAS is compatible with
• Wi-Fi (what we are focusing on today)
• Cellular phone service
• Public safety radio frequencies

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How does it work? Some Definitions
Repeaters an electronic device that receives
signal and retransmits that signal at a higher
level and/or higher power, or onto the other side
of an obstruction, so that the signal can cover
longer distances
 
 
 
 
 
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How does it work? Some Definitions
Picocells or Wi-Fi access point A wireless
communication system typically covering a small
area such as a single home
Although you may be able to connect to your
neighbors internet there is massive signal
degradation
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How does it work?
Alternatively, with DAS an entire neighborhood
could share one internet connection
 
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How does it work?

• This same idea can be applied in large buildings
  (Dormitories, office buildings etc...)

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Why should we care about DAS?

• DAS would allow for wireless internet access
  throughout the Dormitories
• DAS may eventually be implemented in your home
  town (creating a mostly wireless Municipal Area
  Network or Wide Area Network)
• Many corporations and business are switching to
  DAS as building wide wireless access becomes
  essential
• DAS, if installed by phone companies, will rid us
  of dead spots in buildings

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Common Business Applications of DAS

• Universities
• Ameristar Casino
• Hartsfield-Jackson Atlanta International Airport

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Universities

• Current Issues and Problems
• Hard Wire Phones
• Portable Radio Operations
• Student Expectations
• Wireless Providers
• Solutions
• Auburn University
• Implemented BearingPoint
• Eliminated fixed-line telephones
• Extend wireless carrier coverage inside and
  outside university buildings
• Notre Dame, San Diego State, California
  Santa-Crus
• Implemented NextG
• extend existing, limited coverage both indoors
  and outdoors

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Ameristar Casino

• Current Issues
• Enhancement of wireless communication
• Physical structure and layout
• Solution
• Implementation of PowerWaves Linknet Platform
  DAS system
• Results
• Customer Satisfaction
• Operations
• Reduction of infrastructure implementation costs
• Reduction of the number of antennas and
  components used

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Hartsfield Jackson Atlanta International Airport

• Current Issues
• Physical Structure and Layout
• Wireless Signal
• Solution
• Implementation of DAS system
• Results
• Universal Cellular/PCS/Safety Radio Coverage
• Neutral-Host Wireless System
• Booster for Current and Future Mobile
  Applications with Excellent Network Quality

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Business Benefits

• Wireless Support and Security
• Coverage and Capacity
• Increased Productivity

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Wireless Support and Security

• Capable of connecting to all types of wireless
  devices and services including cell phones, Wi-
  Fi, public safety radio, and medical wireless
  systems on same network without interruption of
  one another
• Centralized hub can help to provide better
  security
• Common to use DAS system in medical surgery rooms
  based on need to isolate devices and not be
  affected by other wireless frequencies

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Coverage and Capacity

• Increases indoor signal in all areas within DAS
  range
• Long distance high frequency connectivity
• Range from 10,000 sq. ft. to millions of sq. ft
• Easily add extra capacity by connecting to
  central hub
• Also eliminates need for a tower and conventional
  antennas

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Increased Productivity

• Allows for use of several wireless devices (ex.
  cell phones) indoors with increased signal
  strength and avoids dropped calls
• Brent Frerck, senior technical engineer at May
  Kay..."I can walk out of my CIO's office on the
  13th floor, get on my cell phone, and take the
  elevator all the way down to the fourth level of
  the underground parking garage without dropping a
  call.
• They estimated it increased employees work by an
  hour by cutting out dead cell areas and not
  missing calls, emails, etc.

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Business Challenges

• Transmission Rates/ Environmental Issues
• Standards
• Costs

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Transmission Rates/Environmental Issues

• Wireless connection and antennas can be affected
  by the environment and the weather
• Despite improving connectivity in dead areas it
  still has slow transmission rates due to working
  with several frequencies on same network.

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Standards

• Neither IEEE or ITU have developed standards for
  DAS
• Leads to competing proprietary technologies
  (similar to networking problems prior to the
  Ethernet standard) moreover there is no
  uniformity amongst DAS services
• Certain organizations/institutions may need
  different types requiring in costly consulting
  fees from third parties

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Costs

• Indoor coverage is averaged to cost close to a
  dollar per sq. ft. which can add up for larger
  buildings and outdoor costs are on case by case
  basis
• Need a schematic design for the routing of cables
  horizontally and vertically
• Several antennas, repeaters, and a central hub
  with wiring can take time to install (usually
  installed in ceilings)
• Could be an unnecessary cost for some businesses
  and there is no clear measurement of costs in
  terms of productivity

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Conclusion

• A Distributed Antenna System (DAS) is a network
  of antenna cables connected to repeaters that
  provides wireless service to all areas in which
  it is installed
• Advantages
• Wireless Support and Security
• Coverage and Capacity
• Increased Productivity
• Disadvantages
• Transmission Rates/ Environmental Issues
• Standards
• Costs

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Conclusion

• Business Applications
• Reoccurring issues among business organizations
  include
• Physical layout of the organizations structure
• Limited Wireless coverage for
• Cellular Service Providers
• WiFi Internet Access
• Radio Frequencies for two-way radios
• As a result of implementing a DAS system common
  results include
• Extended signal coverage for multiple wireless
  services
• Reduction of physical equipment
• Lower long-term infrastructure implementation
  costs

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Questions
25
Review Questions

• Choose the best answer
• 1. Distributed antenna systems are completely
  wireless besides the initial connection into the
  central hub.
• A. True
• B. False

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Review Questions

• Choose the best answer
• 2. Distributed antenna systems use a network of
  antenna cable and a centralized hub where as
  Wi-Fi hot spots require several access points.
• A. True
• B. False

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Questions ?