| Auteur | Rechercher : Chu, W. T.1 |
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| Affiliation | - Conseil national de recherches du Canada. Institut de recherche en construction du CNRC
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| Format | Texte, Article |
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| Conférence | Acoustics Week in Canada, 17-21 October 1994, Ottawa, Ontario, Canada |
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| Sujet | Acoustique |
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| Résumé | System response measurements appear in many areas of scientific and technical investigations. The speed of these measurements has been greatly improved with the advent of FFT analyzers. Conventional FFT analyzers require two channels to measure the system response using white noise as a stimulus. Bias errors such as aliasing, leakage, and picket fence effects have to be properly addressed and random errors have to be minimized by averaging. Uses of deterministic types of periodic signal as stimulus are not common although most of these errors would disappear. The inflexibility of the commercial FFT analyzers may be an important reason. To analyze periodic signals, it is necessary to use an `exact' multiple of the period of the signal to avoid leakage effect. It is also necessary to ensure that the signal frequencies coincide `exactly' with the analysis frequencies to avoid picket fence effect. This will require some tailoring of the sampling frequency and the number of data points. We explore the application of deterministic types of periodic signal for system response measurements using a dual channel A/D converter and a special FFT routine. Two types of periodic signal are discussed: (1) pure tones for single frequency measurements and (2) m-sequence or maximum-length sequence (MLS) for broadband measurements |
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| Date de publication | 1994-09 |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Non |
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| Identificateur | IRC-P-3893 |
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| Numéro du CNRC | NRCC 38494
NRC-IRC-5410 |
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| Numéro NPARC | 20330942 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | 62b692bb-ebf8-4f6f-8c3a-0285129cd9a2 |
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| Enregistrement créé | 2012-07-18 |
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| Enregistrement modifié | 2020-04-27 |
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