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RURAL TELECON ’07

A HYBRID SECTORAL/AD HOC MESH NETWORK ARCHITECTURE FOR RURAL

BROADBAND WIRELESS COMMUNICATIONS

OCTOBER 15, 2007

KEN SCHLAGER, Ph.D., P.E.SOUTHEASTERN WISCONSIN REGIONAL PLANNING COMMISSION

WAUKESHA, WISCONSIN

and

PRESIDENTHIERCOMM, INC.

HARTLAND, WISCONSIN

Supported by:SBIR PHASE II GRANT

U.S. DEPT. OF AGRICULTURECOOPERATIVE STATE RESEARCH, EDUCATION AND EXTENSION SERVICE

GRANT NUMBER: 2006-33610-16317

#131426

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Agenda

• Sectoral Cellular Broadband Wireless– Fourth Generation (4G) Performance– Low Infrastructure Costs– High Gain Active Antennas

• Sectoral Cellular Weaknesses– Serves only fixed users– Lacks redundancy

– 99.9% reliability (?)– Enter adaptive mobile mesh network– A Hybrid Sectoral/Adaptive Mesh

Network

• Public Safety Communications and the 9/11 – Katrina Problem

– Consistent failure of communications networks in major public emergencies

– Ad Hoc Mesh Networks and the DOD– The Kenosha County 4.9/5.8 GHz

Public Safety Communications Project

• Wirlwind– An Ad Hoc Routing System– Architecture Technology Corp.– USDA SBIR Grant

• Kenosha County Project– Fusion of Sectoral/Cellular and

dynamic mobile mesh topologies– Long range, high performance

WiFi– Wirlwind Ad Hoc networking

• The Hybrid Solution– Basic Sectoral Cellular Network– Peer-to-Peer Connect– The User Routing Node– Redundant, Reliable High

Performance Network

• Current Status and Plans

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Conceptual Sectoral Cellular Network

Source: SEWRPC.

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Conceptual Mesh Network

Source: Tropos and SEWRPC.

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Sectoral Cellular Network – Costand Performance

• Infrastructure Cost– Town of Wayne, Wisconsin– Land Area – 36 square miles– Access Point Infrastructure– Four (4) APs– AP Density = 0.1/square mile– Total Cost = $80,000 - $2,200/square mile– Including

– Internet gateway– Network management system– Engineering, installation and training

• Mesh Network Alternative Costs– 16 to 80 APs/square mile– Areal cost: $100,000 - $250,000/square mile

• Sectoral/Cellular Network Performance– 10 – 30 megabits per second range

• Mesh Network Alternative Performance– 1 – 3 megabits per second

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Sectoral Cellular Network – Costand Performancecontinued

Basis of Technology

• Network Topology– Allows for use of higher gain directional antennas– Omnidirectional antenna

– 5 – 8 dBi– Directional antenna

– 14 – 17 dBi– 8 times the signal intensity

• Active Antenna– Antenna with high gain, low noise amplifier– Additional gain of 20 dBi and more– 100 times the signal intensity

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Four Access Point Locations, Town of Wayne, Wisconsin

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Backhaul Network, Town of Wayne, Wisconsin

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Sectoral Cellular SystemWeakness and Remedies

• Limited to Fixed Users– Directional antenna requires fixed location– Nomadic and mobile users require omnidirectional antennas– Limited distance from access point

• Lack of Redundancy– No alternative transmission paths– Reliability goal of 99.9%– Wireless networks now far below this target

• Solution: Users as Nodes– If each user could serve as a node to pass on signals to the sectoral AP, the

performance of the network for nomadic users would be greatly enhanced– Enter Peer-to-Peer wireless communications and dynamic, mobile Ad Hoc

mesh networks

• Solution: Higher Performance Laptop Computers– The Active Omnidirectional Antenna– As a laptop computer attachment– For 25 -30 dBi gain

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Public Safety Wireless Communications and the 9/11 – Katrina Problem

• Consistent Failure of Public Safety Communicationsin Major Public Emergencies

– Oklahoma City– 9/11– Katrina

• Causes of Failure– Power outages– Tower damage– Flooding– Network saturation

• Problem with Current Public SafetyCommunications Systems

– Very low data transfer rates– Networks do not survive a disaster event

• Solution– Networks that are independent of fixed infrastructure– Peer-to-Peer communications

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SEWRPC/HierComm/Architecture Technology Corp.and Kenosha County, Wisconsin

• Objectives– To bring broadband to public safety wireless communications– To solve the network survivability problem– To provide a public/private business model for broadband wireless

communications– To extend the sectoral/cellular network model to nomadic and fixed users

• Task #1 – Long Range 4.9 GHz Wireless Communications– To demonstrate extended range, high gain throughput performance at 4.9

GHz– In mobile public safety vehicles

• Task #2 – Peer-to-Peer Communications– To demonstrate adaptive peer-to-peer wireless communications– With and without infrastructure– Selecting the optimal transmission path– Using Architecture Technology Corp. (ATC) Wirlwind

4.9/5.8 GHz Public/Private Wireless Communications Project

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Project WirlwindWireless Wide Area Incident Network

Technical Partnership

HierComm – RF hardwareArchitecture Technology – Network software

USDA SBIR Grant Recipients

HierComm – Rural Wireless Broadband CommunicationsArchitecture Technology – Wirlwind for US Forest Service

Wirlwind

• Ad Hoc Mobile Mesh Network Software Package• Connects user to strongest signal node• Dynamic mobile or fixed location nodes• Project 25 compliant communications• Send/receive voice or data• Geolocation-based communications

– Two technologies– Ad Hoc routing Real-time geographic tracking of nodes and geomessaging

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Wirlwind: Ad Hoc Routing

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Wirlwind: Ad Hoc Routing—continued

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Wirlwind

Ad Hoc Routing

• SARA – Source Initiated Adaptive Routing Algorithm

• Advantages/Features– Implemented working algorithm

– Not just research– Multi-platform = Windows, Linux– Symmetric and Asymmetric Links

• DOD/DARPA funded

Geolocation

• ATC’s GeoTIDES– Geographically Targeted Information Dissemination System– Communication often involves many different groups at various locations and requires

knowledge of location of people and resources

• Advantages/Features– Dynamically tracks all nodes with GPS– Allows transmission of data to geographic coordinates or regions– Geotracking– Geocasting, Geomessaging

The Technology

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Wirlwind Phase I Prototype

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Kenosha County

Task I – Network Planning

• Preliminary County-Wide Network– Radio propagation modeling– Clutter database

• Demonstration Area Network– Two base Stations– Mobile vehicular users

Task II – Equipment Planning

• Base Station Equipment– 4.9 GHz Transceivers (3)– 5.8 GHz Transceivers (3)– Amplifier Augmentations (6) – 3 inch each frequency band– 4.9 GHz Sectoral Antenna (1)– 5.8 GHz Sectoral Antenna (1)

• Mobile Vehicular user Equipment (4.9 GHz only)– 4.9 GHz omnidirectional antenna– 4.9 GHz high gain amplifier– 4.9 GHz transceiver

4.9/5.8 GHz Public Safety/CommercialWireless Network Demonstration Project

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Kenosha County4.9/5.8 GHz Public Safety/CommercialWireless Network Demonstration Project—continued

Task III – Field Demonstration – High Performance, Low Base Station Density Network

• Test truck testing

• Public safety vehicular installation

• Public safety vehicular testing County-wide network plan confirmation

Task IV – Field Demonstration – Peer-to-Peer Communications

• Training

• Test Truck testing

• Public safety vehicular testing

• Public emergency simulated testing

Task V – Full-scale Deployment Planning

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The Upgraded Sectoral/Cellular Boardband Wireless Network

• Enhanced Sectoral/Cellular Network– Augmented by user repeater nodes– For service to nomadic (laptop) and mobile (cell phone) users– A cost effective solution

• A More Robust Network– For public safety– For commercial WiFi

• A Mostly Software Augmentation– Unlike the hardware-oriented Sectoral/Cellular Network– Wirlwind software in all fixed, nomadic and mobile nodes– Minor hardware adjustments

The Hybrid Solution

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Current Status and Plans

• Wayne, Wisconsin Network– As a model high performance, broadband wireless, rural

communications system– Technological demonstration

– Performance– Reliability

– Business model demonstration– Return on investment (ROI)– CPE cost problem

• Search for a National Partner– Convincing a major telecommunications partner of the viability of the

technology and the business model– Otherwise, progress will be slow