In-order to understand the acoustics of air-bourn and water-bourn signals, research may be carried out on naturally created signals. Certain animals such as bats and dolphins are known to use sonar to navigate and find food, so understanding them may help with medical and geological applications.

To simulate the sonar created by these animals will require a flexible arbitrary waveform generator (AWG) connected to a transducer to generate the output signal. This will need the ability to vary the frequency from a few kHz to several MHz.

The effects of transmitting this signal through water or air can be measured with an oscilloscope connected to a microphone. The sample rate of the oscilloscope should be at least 10 times the maximum frequency generated by the AWG, to ensure accurate measurement of any distortion or attenuation.

A variety of instruments may be used to control and measure these signals including benchtop instruments, PC based instruments or a PXI system as shown below.

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The above system uses a small cube chassis with PXI waveform generator and oscilloscope connected to a PC running windows. The PC controls the PXI instruments using National Instruments LabVIEW or an alternative software environment. The PC may also be connected to the internet to allow night time tests, or interrogation from a remote site.