Summary: Finding Minimum-Power Broadcast Trees for Wireless Networks
NASA's Jet Propulsion Laboratory, Pasadena, California
Apr 01 2004
Algorithms for identifying viable trees have been derived.
Some algorithms have been devised for use in a method of constructing tree graphs that represent
connections among the nodes of a wireless communication network. These algorithms provide for
determining the viability of any given candidate connection tree and for generating an initial set of viable
trees that can be used in any of a variety of search algorithms (e.g., a genetic algorithm) to find a tree that
enables the network to broadcast from a source node to all other nodes while consuming the minimum
amount of total power. The method yields solutions better than those of a prior algorithm known as the
broadcast incremental power algorithm, albeit at a slightly greater computational cost.
It is not possible to give more than a highly abbreviated and oversimplified summary of the method within
the space available for this article. However, to give meaning to even this brief summary, it is necessary
to present some details of the underlying rules, simplifying assumptions, and mathematical constructs in
the following two paragraphs.
Each node is equipped with an omnidirectional antenna. The minimum transmitter power that enables the
jth node to send information to the ith node is proportional to r
ij where rij is the distance from node j to
node i and is a channel-loss exponent that usually lies between 2 and 4, the exact value depending on