1. DT3: Solar-Powered “Connect-on-Demand” Satellite/Radio link for Tanzanian Schools Luis Garcia Eric Hatch Joe Larsen Michael Moulton Rafael Ocampo Rodney Singleton

2. Outline  Background  Overview Design  Design Criteria  Risks  Costs

3. Background  Joint project with Electrical Engineering and Telecommunications  Supply internet access to rural schools in Tanzania  Past projects focused on time sharing computer systems  Currently implementations Baraka Primary SchoolBaraka Primary School Manyara Secondary SchoolManyara Secondary School  VSAT to the internet is at Baraka  Baraka is reliant on solar power  Team 4 will be installing a third installation at Rift Valley Secondary School

4. Overview of Design

5. Software  Design software that will determine if a request for the internet has been made by the user.  Save packets during request before internet boot- up, and send once a connection has been established.  Generate signal to be sent to transmitter for turning on network equipment.

6. AM Radio  Send Signal from Manyara or Rift Valley to Baraka  Transmitters at Manyara and Rift Valley  Receiver at Baraka Low Power ConsumptionLow Power Consumption  Operating on 462MHz AvailabilityAvailability Antenna designAntenna design

7. Decoder  Tone Signals  Prevent unwanted requests

8. Microcontroller Function  Will be used to turn off/on the sub-system using relays.  Will take in 4 inputs:  Battery life Less than 40%Less than 40%  Reset Timer 15 minute timeout15 minute timeout  Internet Request Requests from either Manyara, Rift Valley or BarakaRequests from either Manyara, Rift Valley or Baraka  Internal Clock 11pm curfew11pm curfew

9. Design Criteria Order of Priorities: 1.Low Power Consumption 2.Robustness/Durability 3.Low Maintenance 4.Safety 5.Low Cost

10. Risk Management  Multiple external timers, risk of power consumption.  Remote diagnosing?  Safety of equipment.  Collaboration for multi-seat deployments.

11. Cost Hardware:  Programmable Timers: $5 – $10  Micro Controller: $0  Am transmitter and receiver: $12 – $80  3 Op Amp: $6 – $10  WiMax: $1,900  Wires: $15 – $30  Power Strip: $6 – $20  Project Enclosures: $10 – $80 Software:  Python - $0  Libpcap - $0  All Software is open source

12. In Summary We plan to design an “Connect-on-Demand” internet interface to which students can access the internet at night if necessary. This design will be power efficient and beneficial to the education of the Tanzanian students of all three schools.