Can they transmit simultaneously Linghe KONG

OUTLINE How I got this idea? What’s it? Why to research it? Solution I Solution II Some other possible methods Further works

How I got this idea Exposed & hidden terminal problem

How I got this idea Can the exposed terminals transmit simultaneously

What’s it? Not only the exposed terminal, but more transmit simultaneously…

Why to research it? Increase the spatial reuse Improve the network throughput Reduce the collision Less waiting, transmit simultaneously …

Solution I Spectrum Cognitive Radio + Multi-Channel Channel 1

Solution I Using cognitive radio to design a smart mechanism maybe hard to implement Sense delay Trade-off between the number of channels and the bandwidth Multicast case

Solution II Directional antennas B A B A A B A B Dir TX, Omni RX Omni TX, Omni RX Dir TX, Dir RX Omni TX, Dir RX

Solution II Ask some other free nodes as relay

Solution II Scheduling in Large scale nodes environment Partial tight density, partial loose and maybe cluster-distributing in real case Complex to schedule the relay nodes

Some other possible methods Coding Network coding

Some other possible methods Obviously, network coding is not suitable in this situation, but we can borrow this conception and do more advanced work to solve our problem.

Further works How about multi-cast, any-cast? If the nodes could mobile…? With MPR (Multiple-Packet Reception) technology what will happen?

Thanks Q&A