In other words, the apparent
damping of a system can be changed in a predictable way simply
by multiplying the unit impulse response measurement of a system
by a damped exponential. It became apparent that this could be
used as a window to eliminate “leakage errors” and to improve
the signal to noise ratio of impact measurements. As result, an
exponential window could be applied to both the input force and
the output response signal. An additional force window could be
applied to the force signal to eliminate noise on the force channel
after the impact. These windows have been documented in a
number of references.
4,5