Enabling multi-hop wireless mesh networks with multi-input multi-output (MIMO) functionality boosts network throughput by transmitting over multiple orthogonal
spatial channels (spatial multiplexing) and by performing interference cancellation,
to allow links within interference range to be concurrently active. Furthermore,
if the channel is in a deep fade, then multiple antenna elements at the
transmitter and/or receiver can be used to transmit a single stream, thereby improving
signal quality (diversity gain).
However, there is a fundamental trade-off between boosting individual link performance
and reducing interference, which must be modeled in the process of optimizing
network throughput. This is called the diversity-multiplexing-interference suppression
trade-off. Optimizing network throughput therefore, requires optimizing the trade-off
between the amounts of diversity employed on each link, the number of streams multiplexed
on each link and the number of interfering links allowed to be simultaneously
active in the network.
We present a set of efficient heuristics for one-shot link scheduling and stream
allocation that approximately solve the problem of optimizing network throughput
in a single time slot. We identify the fundamental problem of verifying the feasibility
of a given stream allocation. The problems of general link scheduling and stream
allocation are very closely related to the problem of verifying feasibility.
We present a set of efficient heuristic feasibility tests which can be easily incorporated
into practical scheduling schemes. We show for some special MIMO network
scenarios that feasibility is of polynomial complexity. However, we conjecture that in
general, this problem, which is a variation of Boolean Satisablility, is NP-Complete.
| Identifer | oai:union.ndltd.org:GATECH/oai:smartech.gatech.edu:1853/42735 |
| Date | 22 August 2011 |
| Creators | Srinivasan, Ramya |
| Publisher | Georgia Institute of Technology |
| Source Sets | Georgia Tech Electronic Thesis and Dissertation Archive |
| Detected Language | English |
| Type | Dissertation |
Page generated in 0.0016 seconds