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This document outlines the essential requirements and technologies associated with advanced communication systems, focusing on redundancy for robustness, compatibility with existing systems, and various technologies employed, such as Satellite, RF, Microwave, and Fiber-optics. It discusses satellite communication, remote sensing, microwave links, and the evolution of wireless technologies from 1G to 4G, emphasizing their applications in military and commercial sectors, including automated vehicle location systems. It also explores innovative proposals like airships and their comparison with UAVs and satellites.
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BTS – Communications II Requirements and Technologies CSE 8394
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 CSE 8394
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 CSE 8394
Satellite Remote Sensing • Optical • Radar • Insensitive to weather • Sensitive to ground conditions CSE 8394
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 CSE 8394
Typical Setup CSE 8394
Microwave Repeaters CSE 8394
COFDM Advantages CSE 8394
Advanced Microwave Setup CSE 8394
Advanced Microwave Setup (Relay) CSE 8394
New Technologies Courtesy: ParcelCall CSE 8394
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 CSE 8394
Wireless Technologies (Cont’d) • 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 CSE 8394
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 CSE 8394
New Interesting Proposals • Airships • Comparison with UAVs, Satellites CSE 8394