A system and method for selecting an appropriate transmit power and data rate
at
which a communication signal is transmitted over a link between nodes in a wireless
ad-hoc communication network based on factors such as variations in path loss in
the link, fading conditions, noise level estimation and overall link quality. The
system and method perform the operations of computing path loss in the link based
on information provided to the source node from the destination node pertaining
to characteristics of a message that was transmitted by the source node and received
by the destination node, determining a noise factor at the destination node, and
calculating the power level and rate at which the data is transmitted over the
link from the source node to the destination node based on the path loss and the
noise factor. More specifically, the method calculates the power level based on
the path loss, the noise factor and signal fading, and determines the rate based
on the calculated power level. Furthermore, the path loss is computed dynamically
as conditions of said link change over time. Accordingly, the system and method
are capable of determining the proper level of transmit power and data rate for
assuring that the destination node will receive the data transmitted by the source
node at a reliability of at least 90%.
