Road vehicle moving source beamforming

This PULSE software performs noise source identification of noise radiated from moving road vehicles such as cars and trucks. Acoustic results are displayed in colour contour maps that clearly visualize the noise ‘hotspots’ and show how noise propagates from various locations. This noise map is superimposed on a representation of the vehicle, so the user can clearly see the noise levels from each of the vehicle’s components, such as a tyre or wing mirror, and gain insights into the sound’s directivity.

USE SCENARIOS

• Trackside noise source location on vehicles at speed
• Troubleshooting during pass-by measurements
• Analyzing and ranking noise source contribution to target mitigation efforts
• Communicating sound intuitively

Mapping the whole or part of the vehicle enables differentiation between aerodynamic noise and rolling noise from the interaction of the wheels with the road. Smaller areas such as the windscreen can be targeted, and the contributed sound power can be calculated, thus enabling the user to easily rank the areas in order of importance. Identifying the most important sub-sources of noise such as the engine or front wheels in terms of position, frequency content and sound power radiation helps decide where design changes can most effectively reduce overall noise radiation – either reducing noise levels or optimizing their content and noise propagation.

CAPABILITIES 

• Maps moving noise sources from the side of the vehicle
• Presents acoustic maps of sound pressure
• Displays sound maps versus position, and pressure contribution versus position and frequency
• Presents and communicates results and ideas through tools such as AVI files
• Maps targets much larger than the array itself
• Estimates contribution areas

Users can make any type of signal processing or hear any microphone signal in very high quality, thanks to the system’s high sampling rate of more than 65 kHz per channel. This also enables it to map high frequencies.