1. Andrew Lippman lip@mit.edu October, 2004 Viral Radio

2. Scalable Incremental Contributory Viral Innovation Viral systems are innovative through modularity and distribution of capability -- the intelligence is at the ends e.g.: Fax machines, Internet

3. Viral Radio Open systems such as PCs gain capacity with more units, traditional communications systems divide fixed capacity among elements. Can we make communications systems (telephones, networks) that are viral and economic? Social Context

4. Network Co-generation Delivers realtime information by using intelligent RF Scales adhoc networks by limiting radiation to nodes in between two parties

5. Radios costing less than radio waves (Breadcrumbs) There are no receivers (Receiving costs more than transmitting) Radio Magic Collaboration makes it work

6.  Wireless = Broadcast (it makes it hard… it makes it challenging…) “Wireless Broadcast Advantage” Antenna Sharing: exploits observation of a common “property” across different users (antennas) in space… Our contribution: distributed, “adaptive” algorithms applicable in practice… Direct Multi-hop Cooperative (Special case of co-op) Cooperative Propagation Aggelos Bletsas, 2004

7. Closer is not always the better… fading is not always harmful (MIMO results)… Instantaneous wireless channel conditions matter (not only average) - Algorithms should adapt to wireless propagation “instantaneously” (within channel coherence time) - no need for topology estimation… Propagation Space Aggelos Bletsas, 2004

8. Method of distributed timers = opportunistic relaying Mapping channel conditions to time! Exploiting RTS/CTS packets of MAC and reciprocity… best path = relay that expires first… Collision probability depends on λ (user defined)… RTS CTS Test Case Aggelos Bletsas, 2004

9. Antenna sharing for cooperative position estimation Estimate your location relatively to neighbors with “good” signal paths (high SNR measurements). Prior art found in protein structure determination (“molecular distance geometry problem”)… Local Space and Time Aggelos Bletsas, 2004

10. Radio Magic