72 12 2016 pp. 777 782 777 * 43.60.Pt; 43.38.Md; 43.60.Sx 1. 1 2 [1 8] Flexible acoustic interface based on 3D sound reproduction. Yosuke Tatekura (Shizuoka University, Hamamatsu, 432 8561) 2. 2.1 3 M N m (= 1, 2,,M) S m n (= 1, 2,,N) C n G nm (ω) G(ω) G 11 (ω) G 1M (ω) G(ω) =..... (1) G N1 (ω) G NM (ω) ω H(ω) X(ω)
778 72 12 2016 1 3 H(ω) = ( G H (ω)g(ω) ) 1 G H (ω) (6) 2 H 11 (ω) H 1N (ω) H(ω)=....... (2) H M1 (ω) H MN (ω) [ X(ω)= X 1 (ω) X 2 (ω) X N (ω) ] T (3) ˆX(ω) [ T ˆX(ω) = ˆX1 (ω) ˆX2 (ω) ˆXN (ω)] = G(ω)H(ω)X(ω) (4) ˆX(ω) =X(ω) (4) G(ω)H(ω) =I N (5) H(ω) I N N N G(ω) M N M = N H(ω) =G 1 (ω) M <N H M >N H(ω) =G H (ω) ( G(ω)G H (ω) ) 1 (7) G(ω) [9] [10] 2.2 (5) 1 n X n (ω) n 1 X n (ω) 0 n n 0 n X n (ω) X n (ω)
779 1 (5) X n (ω) n n 2.3 11 2015 16 4 4 8 ROLAND OCTA-CAPTURE UA- 1010 2 Bose Companion 20 8 Sony ECM-44B 8 USB PC 4 4 MATLAB MATLAB pa-wavplay [11] TSP [12] [13] 4 0.4 3 3. 3.1 2.3
780 72 12 2016 5 [14, 15] 3.2 5 M N N E (N N E ) X(ω) X n (ω) N N X n (ω) f T (L), (H) ω <f T H (L) (ω) ω f T H (H) (ω) H (L) 11 (ω) H(L) 1N (ω) H (L) (ω)=....... H (L) M1 (ω) H(L) MN (ω) (8) H (H) (ω) = H (H) 1(N E +1) (ω) H(H) 1N (ω). O........ M,NE H (H) M(N E +1) (ω) H(H) MN (ω) (9) H (L) (ω), H (H) (ω) M N O M,NE M N E ˆX(ω) G(ω)H ˆX(ω)= (L) (ω)x(ω) G(ω)H (H) (ω)x(ω) if ω<f T otherwise (10) 3.3 6 2 1 6 [16] 12 8 6 Area A B Area A B 4 6 8 6 0.46
781 7 SCR 6 8,000 Hz 4,096 16,384 150 3,850 Hz 500 Hz [17] Width: 2.50 3.00 m Male area Width: 3.00 3.50 m Female area SCR Signal to Crosstalk Ratio SCR [db]=10 log 10 t d P (t) 2 t ˆx P (t) d P (t) 2 (11) t ˆx P (t) P d P (t) P SCR 7 8 SCR Area A B 3.4 6 8 SCR 40 5cm 3 3 6 Sp1 Sp8
782 72 12 2016 9 20 8 Scheffé [18] 7 +3: +2: +1: 0: 1: 2: 3: 9 95% 2 4. [ 1 ] T. Betlehem, W. Zhang, M. A. Poletti and T. D. Abhayapala, Personal sound zones: Delivering interface-free audio to multiple listeners, IEEE Signal Process. Mag., 32, 81 91 (2015). [ 2 ] J. Chang, C. Lee, J. Park and Y. Kim, A realization of sound focused personal audio system using acoustic contrast control, J. Acoust. Soc. Am., 125, 2091 2097 (2009). [ 3 ] Y. J. Wu and T. D. Abhayapala, Spatial multizone soundfield reproduction: Theory and design, IEEE Trans. Audio Speech Lang. Process., 19, 1711 1720 (2011). [ 4 ] T. Okamoto, Generation of multiple sound zones by spatial filtering in wavenumber domain using a linear array of loudspeakers, Proc. ICASSP 2014, 4733 4737 (2014). [ 5 ] Y. Nakayama, M. Adachi, K. Ishimoto and Y. Tatekura, Individual sound image generation for multiple users based on loudspeaker array with NB- SFC, Proc. DSP 2013 (2013). [6],,,,, (A), J97-A, 304 312 (2014). [ 7 ] M. F. Galvez, S. J. Elliott and J. Cheer, Personal audio loudspeaker array as a complementary TV sound system for the hard of hearing, IEICE Trans. Fundam., E97-A, 1824 1831 (2015). [ 8 ] T. Shimizu, J. Trevino, S. Sakamoto and Y. Suzuki, A multi-zone approach to sound field reproduction based on spherical harmonic analysis, Acoust. Sci. & Tech., 36, 441 444 (2015). [9],,,, 69, 276 284 (2013). [10] Y. Tatekura, S. Urata, S. Saruwatari and K. Shikano, On-line relaxation algorithm applicable to acoustic fluctuation for inverse filter in multichannel sound reproduction system, IEICE Trans. Fundam., E88-A, 1747 1756 (2005). [11] http://www.mathworks.com/matlabcentral/ fileexchange/47336-pa-wavplay-for-32-bit-and-64-bit 2016-10-19. [12], Swept-Sine,, 63, 322 327 (2007). [13] T. Amano and Y. Tatekura, Multichannel simultaneous measurement of room impulse responses using instrument part sounds of ensemble music, Proc. WESPAC 2015 (2013). [14],,, (A), J95-A, 640 644 (2012) [15],,,, 1-10-14 (2013.3). [16],,,,, 5, 957 964 (2000). [17] J. B. Allen and D. A. Berkley, Image method for effeciently simulating smallroom acoustics, J. Acoust. Soc. Am., 65, 943 950 (1979). [18],,, 1973.