Wing Shing Wong, Chinese University of Hong Kong

Location :

ENS
équipe-projet TREC
(bâtiment principal de la direction, 2ème étage)
45 rue d'Ulm
75005 Paris
Acces : http://www.di.ens.fr/AccesDI.html

Abstract :

Protocol sequences were pioneered by Massey and Mathys in the eighties of the last century.  
These sequences were designed to address multiple access control problems in wireless 
networks.   An attractive feature provided by this approach is that transmitters do not listen to the 
media at any time and yet the system can achieve the 1/e maximum throughput of slotted 
ALOHA asymptotically.  This makes it a good candidate for lightweight transceiver applications, 
such as sensor networks.  However, a drawback is the long period required for the protocol 
sequences.  In this talk, we will report some recent advances on our understanding of the 
structure and cross-correlation properties of protocol sequences, ranging from shift-invariance 
sequences, as exemplified by Massey's original construction, to prime sequences.  We will also 
present new constructions such as the wobbling sequences and CRT sequences, which effectively 
address the long periodicity problem.  We will also point out potential future applications of 
protocol sequences beyond the domain of multiple access control.  

Host :

Ecole Normale Supérieure