Wideband beam pattern
Original version
This report is not to be cited without prior reference to the authorAbstract
Transducer directivity is important in the basic acoustic surveying
methods of echo counting and integration. In quantifying the directivity,
the beam pattern is often computed assuming ideal single-frequency
operation. The validity of this for typical pulsed signals and receivers
is examined. A wideband beam pattern is defined and computed for several
different combinations of transducer geometry, transmit pulse duration,
and receiver frequency response function. For each, the directivity index
and equivalent beam angle are computed and compared with the respective
single-frequency estimates.