A
system for providing an accurate prediction of a
signal-to-interference
noise ratio is described. The
system includes a first circuit for receiving a
signal transmitted across a channel via an external
transmitter. A second circuit generates a sequence of estimates of
signal-to-interference
noise ratio based on the received signal. A third circuit determines a relationship between elements of the sequence of estimates. A fourth circuit employs the relationship to provide a signal-to-interference
noise ratio prediction for a subsequently received signal. In the illustrative embodiment, the inventive
system further includes a circuit for generating a
data rate request message based on the signal-to-noise ratio prediction. A special
transmitter transmits the
data rate request message to the external
transmitter. In the specific embodiment, the relationship between elements of the sequence of estimates is based on an average of the elements of the sequence of estimates. The third circuit includes a
bank of filters for computing the average. The
bank of filters includes
finite impulse response filters. Coefficients of the transfer functions associated with each filter in the
bank of filters are tailored for different
fading environments. The different
fading environments include different
Rayleigh fading environments, one environment associated with a rapidly moving system, a second environment associated with a slow moving system, and a third system associated with a system moving at a medium velocity. A selection circuit is connected to each of the filter banks and selects an output from one of the filters in the
filter bank. The selected output is associated with a filter having a
transfer function most suitable to a current
fading environment.