Software

PNCA-R software

The Panel Noise Contribution Analysis Reference-Related (PNCA-R) software is add-on to the Near Field Acoustic Camera. This PNCAR module has advanced processing options for panel noise contribution analysis or airborne transfer path analysis. The recorder module of the the Near Field Acoustic Camera is used to record the data.

The Panel Noise Contribution Analysis is a well-known methodology for an airborne Transfer Path Analysis (TPA) in car interior. Pressure contribution from the individual panels at a reference point can be very accurately calculated. Acoustic Trim package treatment can therefore be optimized in terms of frequency and panel area which saves money and time. The method uses only one type of sensors so called particle velocity probes for measuring source strength as well as transfer function (with a reciprocal measurement).

The new Panel Noise Contribution Analysis Referenced (PNCAR) implements a new post-processing technique which uses a reference sensor in order to extract the relative phase information for the individual panel and frequency of interest. This technique makes it possible to use a limited amount of probes for measuring a whole car interior. Typically 11 probes are used in 11 sessions. Consequently, the methodology becomes more robust and commercially more affordable than conventional PNCA.

The PNCAR software module has the                
option to display the following quatities:
The following analyse option can be selected:

Measurement procedure

The first step is to measure in the vehicle, during operational running condition. This step can be done in a laboratory but it is also possible to perform the measurement while driving the vehicle on the road, to include e.g. wind and tire noise. Stationary as well as non-stationary running conditions, such as run ups are accessible and do not limit the applicability of the method. The source strengths are determined by measuring the acoustic particle velocity close to the panel surfaces.

The second step is the determination of the transfer paths from the panels to a certain listening position. This measurement is done reciprocally by using an omnidirectional sound source at the listener’s position and measuring the sound pressures close-by the panels. Both steps are recorded using the Acoustic Camera Recorder. In the last step both data, source strength and transfer paths, are linked in the PNCA-R software module. The results can be analyzed and investigated with different features offered in the PNCAR software module.

The validation of the measurement is done through a comparison between the reference pressure measured at a position and the pressure synthesized ( SPL vs Sum of all contributions ). The pressure dispersion measured at the reference position during the different sessions is also used as validation to ensure accurate and correct measurement results.

 

The latest release of the software is: PNCA-R 1.0