Events

 
PhD Thesis Presentation
Interference Alignment for Wireless Communication Networks

by Mr Liangzhong RUAN

Date
 :  11 Oct 2013 (Fri)
Time
 :  9am
Venue  :  Room 4480, 4/F (Lifts 25-26), HKUST

Examination Committee
Prof Ying ZHAO, MARK/HKUST (Chairman)
Prof Vincent LAU, ECE/HKUST (Thesis Supervisor)
Prof Soung Chang LIEW, Department of Information Engineering, The Chinese University of Hong Kong (External Examiner)
Prof Roger S K CHENG, ECE/HKUST
Prof Daniel PALOMAR, ECE/HKUST
Prof Wei Ping LI, MATH/HKUST
 
Abstract
 
Interference alignment (IA) has attracted enormous research interest as it achieves optimal throughput scaling with respect to signal to noise ratio in a wide range of networks. However, despite the numerous works dedicated to IA, its theoretical foundation is still incomplete. In particular, two fundamental issues, i.e. feasibility conditions and algorithm design, remain open problems in general. The feasibility conditions are hard to determine because IA constraints are sets of nonlinear equations, and the algorithm design is challenging because interference minimization problems are non-convex. There is no systematic tool to address either issue.
 
In this thesis, by adopting methodologies from algebraic geometry, I have established a framework that shows the (almost surely) equivalence between 1) feasibility of IA, 2) algebraic independence of IA constraints, 3) linear independence of the coefficient vectors of the first order terms in IA constraints, and 4) full rankness of the Jacobian matrix of IA constraints. This framework determines the feasibility conditions of IA on MIMO interference networks, generates a set of algorithms to find IA solutions, and hence set up a theoretical basis for IA.
 
Further, I have extended the applicable range of IA in two dimensions: 1) from fully connected interference networks to partially connected interference networks; 2) from interference networks to cellular networks.
 
 
*** ALL ARE WELCOME !! ***