BTS

1
BTS Communications II

• Requirements and Technologies

2
BTS Communication

• Requirements
• Redundant links for robustness
• Terrain and distance dependent
• Compatible/non-interfering with existing systems
• Technologies
• Satellite
• RF, Microwave
• Fiber-optic
• Commercial phones (land lines and wireless
• IP Links

3
Satellite Orbits

• Low Earth Orbit (LOE)
• 200- 1000 Miles Above Ground Level
• .03 Second Roundtrip Latency for Upload and
  Download
• Used by military satellites
• Middle Earth Orbits (MEO)
• 6250 - 13000 Miles Above Ground Level
• .06 to .14 Second Roundtrip Latency
• Geo-synchronous Orbit
• 22,300 Miles Above Ground Level
• .24 Second Roundtrip Latency
• Used by most commercial satellites

4
Satellite Remote Sensing

• Optical
• Radar
• Insensitive to weather
• Sensitive to ground conditions

5
Microwave Links

• Benefits
• No need to dig
• Only option over inhospitable terrain or
  congested areas
• Despite low cost, broadcast level video quality
• COFDM (Coded Orthogonal Frequency Division
  Multiplex) helps in the noisy urban areas
• Excellent for ad hoc deployment
• Specs
• Single channel (To collecting points)
• Multi-channel

6
Typical Setup
7
Microwave Repeaters
8
COFDM Advantages
9
Advanced Microwave Setup
10
Advanced Microwave Setup (Relay)
11
New Technologies
Courtesy ParcelCall
12
Generations of Wireless Technologies

• 1G 1979-1992 analog wireless technology
• 2G current digital wireless technology
• TDMA (GSM Global Systems of Mobile
  Communication)
• CDMA
• 2.5G interim technology accommodates graphics
• 3G non-IP based technology (2001-2005) supports
  rich media (video clips)
• 4G fully IP-based network (2006-2010)
• GPRS General Packet Radio Services
• WCDMA Wideband CDMA

13
Wireless Technologies (Contd)

• GPS Satellite-based Global Positioning System
• SMS Short Message Service (e-mail, up to 160
  characters)
• EMS Enhanced Messaging Service
• Extension of SMS simple animation, tiny picture,
  short melody
• MMS Multimedia Messaging Service
• Rich media of next generation
• UMTS Universal Mobile Telecommunications System
  for 3G mobile standard
• WAP Wireless Application Protocol for Internet
  Browsing

14
Automated Vehicle Location (AVL)

• GPS to track vehicles
• Already more than a million vehicles in the US
  with AVL
• 3 billion business by 2007
• In line with the new vision for BTS

15
New Interesting Proposals

• Airships
• Comparison with UAVs, Satellites