NeTS: Small: Wireless Multihop Networking with MIMO

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

Wireless networks have had a profound impact on the way people work and live. With the advent of mesh networks and WiMax, wireless multihop networks could have a similar impact by providing the last piece of a ubiquitous networking infrastructure. However, wireless multihop networks are subject to a capacity limit, as set forth in the classic work by Gupta and Kumar. Of different technologies proposed for throughput enhancement, the use of MIMO links is especially promising. This project considers how to use MIMO resources optimally to achieve network-wide performance goals. MIMO resources can be used to increase single-link performance through array and diversity gains and spatial multiplexing of streams, or to activate otherwise conflicting links simultaneously through interference suppression. The proposed research characterizes the inherent tradeoffs among these capabilities. The PIs are addressing the problem through both formal optimization techniques and algorithm design and analysis. Algorithms for evaluating feasibility of a set of MIMO links, for scheduling streams across a MIMO network, and for routing of flows are being developed. Our problem formulations account for important MIMO characteristics that were ignored in prior work on MIMO networks. From these more accurate models, the PIs are designing MIMO-aware algorithms that will enable major throughput gains. In addition to the formal analyses and new algorithms that will result from this research, they are integrating MIMO models and algorithms into the ns-3 network simulator. This is expected to spur additional research into the benefits of MIMO from the broader wireless networking community.