| Zugriffsnummer | 17865 |
| Dokumenttyp | Konferenzartikel |
| Sprache | Englisch |
| Titel | Methods for the phase calibration of hydrophones |
| Autor(in); Institution |
Koch, Christian; 1.6, Schall, PTB-Braunschweig
Wilkens, Volker; 1.6, Schall, PTB-Braunschweig
|
| Quelle/Jahr | Inter-Noise - Rio 2005 : the 2005 International Congress and Exposition on Noise Control Engineering:(2005) |
| Availability | [CD-ROM] ; file name: doc_2072.pdf |
| Herausgeber(in) |
I-INCE, International Institute of Noise Control Engineering
|
| Verlag | Rio de Janeiro: Brazilian Acoustical Society |
| Konferenzangaben | 34th International Congress and Exposition on Noise Control Engineering, Rio de Janeiro, 07-10, August, 2005, Brazil |
| Zusammenfassung | To date, primary and secondary hydrophone calibration techniques provide the amplitude of the hydrophone sensitivity of internal standards or for a calibration service. In many applications precise and reliable measurements are, however, impeded by the non-ideal transfer characteristic of the hydrophone, and deconvolution procedures are necessary for data correction, which requires the complex sensitivity of the hydrophone being determined. Three generally different methods are presented providing the complex hydrophone sensitivity. Two techniques are based on the principles of time-delay spectrometry (TDS). In the first technique heterodyning is used to ensure a fixed phase relation between transmitting and receiving voltage at the ports of a network analyser. The second method separates unwanted signals from the measurement information in the time domain using a fast Fourier transform (FFT). TDS is, however, a substitution technique that needs a suitable \\"absolute\\" standard. Thus, an alternative third method applies nonlinearly distorted, focused ultrasound pulses to the hydrophones also providing a comparison of phase responses. With the help of this technique, an optical multilayer hydrophone showing an extremely flat amplitude and phase response could be exploited as a phase reference. Transfer standard devices were calibrated for application by TDS since the pulse technique is limited to small diameter hydrophones. |
