| Presentation | 2012-05-24 An Evaluation of Demodulation for Parametric Loudspeaker based on Spectral Envelope Daisuke IKEFUJI, Masato NAKAYAMA, Masanori MORISE, Takanobu NISHIURA, |
|---|---|
| PDF Download Page |  PDF download Page Link |
| Abstract(in Japanese) | (See Japanese page) |
| Abstract(in English) | Parametric loudspeakers with sharper directivity can reproduce audible sounds to a particular area. Parametric loudspeakers emit an intense amplitude modulated wave designed by modulating the ultrasound with the audible sound. The emitted amplitude modulated wave is demodulated into the original audible sound because of a nonlinear interaction in the air. Demodulation ratio depends on power spectrum and sound pressure of the demodulated sound. In other words, reproduction of accurate sound with parametric loudspeakers needs the sufficient demodulation distance. Demodulation is evaluated by sound pressure level of the demodulated sound. However, no criterion has been proposed for measuring the demodulation ratio in the past. We therefore propose criterion to measure of demodulation ratio based on spectral envelope which indicates a shape of power spectrum. As a result of the evaluation experiment, we confirmed the effectiveness of the proposed criterion. Moreover, we confirmed the demodulation ratio depends on the sub-band of the audible sound. |
| Keyword(in Japanese) | (See Japanese page) |
| Keyword(in English) | Parametric loudspeaker / Ultrasound / Demodulation ratio / Spectral envelope / Evaluation criterion |
| Paper # | EA2012-13,SIP2012-13,SP2012-13 |
| Date of Issue |
| Conference Information | |
| Committee | SP |
|---|---|
| Conference Date | 2012/5/17(1days) |
| Place (in Japanese) | (See Japanese page) |
| Place (in English) | |
| Topics (in Japanese) | (See Japanese page) |
| Topics (in English) | |
| Chair | |
| Vice Chair | |
| Secretary | |
| Assistant | |
| Paper Information | |
| Registration To | Speech (SP) |
|---|---|
| Language | JPN |
| Title (in Japanese) | (See Japanese page) |
| Sub Title (in Japanese) | (See Japanese page) |
| Title (in English) | An Evaluation of Demodulation for Parametric Loudspeaker based on Spectral Envelope |
| Sub Title (in English) | |
| Keyword(1) | Parametric loudspeaker |
| Keyword(2) | Ultrasound |
| Keyword(3) | Demodulation ratio |
| Keyword(4) | Spectral envelope |
| Keyword(5) | Evaluation criterion |
| 1st Author's Name | Daisuke IKEFUJI |
| 1st Author's Affiliation | Graduate School of Science and Engineering, Ritsumeikan University() |
| 2nd Author's Name | Masato NAKAYAMA |
| 2nd Author's Affiliation | College of Information Science and Engineering, Ritsumeikan University |
| 3rd Author's Name | Masanori MORISE |
| 3rd Author's Affiliation | College of Information Science and Engineering, Ritsumeikan University |
| 4th Author's Name | Takanobu NISHIURA |
| 4th Author's Affiliation | College of Information Science and Engineering, Ritsumeikan University |
| Date | 2012-05-24 |
| Paper # | EA2012-13,SIP2012-13,SP2012-13 |
| Volume (vol) | vol.112 |
| Number (no) | 49 |
| Page | pp.pp.- |
| #Pages | 7 |
| Date of Issue | |