On the geometry of wireless network multicast in 2-D

31 May 2011

Bibliographic Details
Main Authors: Thakur, Mohit (Author), Fawaz, Nadia (Author), Medard, Muriel (Contributor)
Other Authors: Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science (Contributor), Massachusetts Institute of Technology. Research Laboratory of Electronics (Contributor)
Format: Article
Language:English
Published: Institute of Electrical and Electronics Engineers (IEEE), 2012-10-10T13:28:39Z.
Subjects:
Online Access:Get fulltext
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100 1 0 |a Thakur, Mohit  |e author 
100 1 0 |a Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science  |e contributor 
100 1 0 |a Massachusetts Institute of Technology. Research Laboratory of Electronics  |e contributor 
100 1 0 |a Medard, Muriel  |e contributor 
700 1 0 |a Fawaz, Nadia  |e author 
700 1 0 |a Medard, Muriel  |e author 
245 0 0 |a On the geometry of wireless network multicast in 2-D 
260 |b Institute of Electrical and Electronics Engineers (IEEE),   |c 2012-10-10T13:28:39Z. 
856 |z Get fulltext  |u http://hdl.handle.net/1721.1/73692 
520 |a 31 May 2011 
520 |a We provide a geometric solution to the problem of optimal relay positioning to maximize the multicast rate for low SNR networks. The network we consider consists of a single source, multiple receivers and the only intermediate and locatable node as the relay. We construct network the hypergraph of the system nodes from the underlying information theoretic model of low-SNR regime that operates using superposition coding and FDMA in conjunction (which we call the "achievable hypergraph model"). We make the following contributions. 1) We show that the problem of optimal relay positioning maximizing the multicast rate can be completely decoupled from the flow optimization by noticing and exploiting geometric properties of multicast flow. 2) All the flow maximizing the multicast rate is sent over at most two paths, in succession. The relay position depends on only one path (out of the two), irrespective of the number of receiver nodes in the system. Subsequently, we propose simple and efficient geometric algorithms to compute the optimal relay position. 3) Finally, we show that in our model at the optimal relay position, the difference between the maximized multicast rate and the cut-set bound is minimum. We solve the problem for all (P[subscript s],[subscript Pr]) pairs of source and relay transmit powers and the path loss exponent α ≥ 2. 
546 |a en_US 
655 7 |a Article 
773 |t Proceedings on the IEEE International Symposium on Information Theory Proceedings (ISIT), 2011