Current wireless network solutions are based on a link abstraction where asingle co-channel transmitter transmits in any time duration. This model severelylimits the performance that can be obtained from the network. Being inherently anextension of a wired network model, this model is also incapable of handling theunique challenges that arise in a wireless medium. The prevailing theme of thisresearch is to explore wireless link abstractions that incorporate the broadcast andspace-time varying nature of the wireless channel. Recently, a new paradigm forwireless networks which uses the idea of 'cooperative transmissions' (CT) has garneredsignificant attention. Unlike current approaches where a single transmitter transmitsat a time in any channel, with CT, multiple transmitters transmit concurrently afterappropriately encoding their transmissions. While the physical layer mechanisms forCT have been well studied, the higher layer applicability of CT has been relativelyunexplored. In this work, we show that when wireless links use CT, several networkperformance metrics such as aggregate throughput, security and spatial reuse canbe improved significantly compared to the current state of the art. In this context,our first contribution is Aegis, a framework for securing wireless networks againsteavesdropping which uses CT with intelligent scheduling and coding in Wireless LocalArea networks. The second contribution is Symbiotic Coding, an approach to encodeinformation such that successful reception is possible even upon collisions. The thirdcontribution is Proteus, a routing protocol that improves aggregate throughput inmulti-hop networks by leveraging CT to adapt the rate and range of links in a flow.Finally, we also explore the practical aspects of realizing CT using real systems.
【 预 览 】
附件列表
Files
Size
Format
View
Cooperative communication in wireless networks: algorithms, protocols and systems
PDF
download
878987797
028-85220240
