1 / 11

Intelligent Antenna Sharing for Efficient Wireless Networks

This paper explores the concept of antenna sharing in wireless networks, leveraging the observation of common properties across different users. The study presents distributed and adaptive cooperative algorithms applicable in practice, focusing on data, time, and location. The paper also discusses the benefits of opportunistic relaying and cooperative diversity, and proposes algorithms for network synchronization and position estimation. The goal is to improve network performance, scalability, and adaptability to the environment.

hayeslinda
Download Presentation

Intelligent Antenna Sharing for Efficient Wireless Networks

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Intelligent Antenna Sharing in Wireless Networks Aggelos Bletsas aggelos@media.mit.edu Viral Communications Group MIT Media Lab - Fall 2004

  2. Wireless = Broadcast (it makes it hard… it makes it challenging…) Direct Multi-hop Cooperative (~100 years old) (~35 years old) (~today…) • “Wireless Broadcast Advantage” • Antenna Sharing: exploits observation of a common “property” across different users (antennas) in space… • “Property”= data, time, location… • Our contribution: distributed and adaptive cooperative algorithms, applicable in practice…

  3. d Tx Rx • Closer is not always better [Goud Jr et. al 2004]… 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…

  4. Diversity (including repetition)…wasteful, does not scale… • Cooperative diversity:complex space-time coding…receiver hardware might be non linear (superposition does not apply)… • Opportunistic Relaying:pick “best” relay (“best” relay = best end-2-end path)no communication among relays needed(distributed, “real time” solution)

  5. RTS CTS Method of distributed timers = opportunistic relaying Mapping channel conditions to time! Harmonic mean • Exploiting RTS/CTS packets of MAC and reciprocity…best path = relay that expires first… • Collision probability depends on λ (user defined)…

  6. 2 relays Better performance 7 relays Outage vs SNR • Performance increases with number of relays… • Need for less transmission power… (less interference = scalability) SEP vs SNR

  7. Picking best relay leads to higher capacity compared to picking a set of relays, for fixed total transmission power!

  8. Relays Implementation of opportunistic relaying using low cost, embedded radios… Rx/display Tx

  9. Antenna sharing for cooperative time keeping End-2-End Error Diameter of network • Distributed Synchronization – server free, scalable • Scalable = larger network, better performance

  10. 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”)… • More on this in separate lecture…

  11. Intelligent Antenna Sharing in Wireless Networks • Practical, Adaptive to the environment Algorithms. • Distributed Algorithms. No need for network topology knowledge. • Algorithm could be implemented to non-linear receivers. • “See Around Corners” ability… • Antenna Sharing is extended to efficient network timing/positioning.

More Related