To measure a point-to-point transfer function for pressure radiation, the instrument
is taken into an anechoic chamber, and excited with a shaker with white noise as input
or with a force-hammer, in which case the force input into the system is close to an impulse.
The signal generated from the motion of the instrument is recorded using a microphone
a distance away from the instrument. With the acceleration and pressure signals recorded,
a transfer function is computed .