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AN ANALOG INTEGRATED-CIRCUIT VOCAL TRACT

PRESENTED BY:
NIEL V JOSEPH
S7 AEI
ROLL NO-46
COLLEGE OF ENGINEERING, TRIVANDRUM
2007-11 BATCH


CONTENTS
Introduction
Human vocal tract
Concept of speech locked loop
Circuit model of vocal tract
Two -port ∏ -section
Linear and non linear resistor modeling
Driving the vocal tract
conclusion

INTRODUCTION
First experimental integrated circuit vocal tract
16 stage cascade of two port ∏-elements
Analysis by synthesis
Speech locked loop

Human vocal tract
Function is filtering of sound
Consist of laryngeal cavity, pharynx, nasal cavity and oral cavity
Length in adult males is 16.9 cm and in females 14.1cm
Larynx produces sound in mammals
Lungs act as power supply
controlled variations in the area of vocal tract produces speech
Two sources of excitation are
Periodic source at the glottis
Turbulent noise source at some point along the tube
Vocal fold vibrations produces interruption of airflow

CONCEPT OF SPEECH LOCKED LOOP

CIRCUIT MODEL OF VOCAL TRACT
Vocal tract is assumed as non-uniform acoustic tube
Terminated by the vocal chord at one end and lip/nose at other end
Cross sectional area is varied by changing impedances at different points
Propagation of wave is approximately one dimensional

The wave equation for one dimensional sound propagation in a uniform tube of circular cross section is
Acoustic wave propagation in a tube is analogous to plane wave propagation along an electrical transmission line
Equation can be modified as
Transmission Line (TL) model
TL comprises of cascade of two-port elements
Current source model
Variable impedance model
Fluid volume velocity is mapped to current
Fluid pressure is mapped to voltage

TWO-PORT pi-SECTION

LINEAR AND NON LINEAR RESISTOR MODELING
Implemented with MOS transistor
Glottal constriction resistance is a series combination of linear and non linear resistors
For linear characteristics I ∞V
For non linear characteristics I ∞√V

DRIVING THE VOCAL TRACT
It can produce all speech sounds
We should be given area function, the glottal excitation source, the turbulent noise source
Area function has large number of degrees of freedom
To reduce the dimensionality we use Maeda articulatory model

The Maeda articulatory model describes the vocal tract profile using seven components
Jaw height
Tongue body position
Tongue body shape
Tongue tip
Lip height
Lip protrusion
Larynx height

For many speech synthesis applications 5-7kHz is sufficient

REFERENCES
B. Raj, L. Turicchia, B. Schmidt-Nielsen, and R. Sarpeshkar, “An FFTbased
companding front end for noise-robust automatic speech recognition,”
EURASIP J. Audio, Speech, Music Process., vol. 2007, 2007,
10.1155/2007/65420, Article ID 65420.
R. Sarpeshkar, M. W. Baker, C. D. Salthouse, J. Sit, L. Turicchia, and
S. M. Zhak, “An ultra-low-power programmable analog bionic ear processor,”
IEEE Trans. Biomed. Eng., vol. 52, no. 4, pp. 711–727, Apr.
2005.
L. Turicchia and R. Sarpeshkar, “A bio-inspired companding strategy
for spectral enhancement,” IEEE Trans. Speech Audio Process., vol.
13, no. 2, pp. 243–253, Mar. 2005.

A ppt of the topic is also available at:
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ABSTRACT
We present the first experimental integrated-circuitvocal tract by mapping fluid volume velocity to current, fluidpressure to voltage,and linear and nonlinear mechanical impedancesto linear and nonlinear electrical impedances.The 275 µanalog vocal tract chip includes a 16-stage cascade of two-port -elements that forms a tunable transmission line, electronicallyvariable impedances, and a current source as the glottal source. Anonlinear resistor models laminar and turbulent flow in the vocaltract. The measured SNR at the output of the analogvocal tractis 64, 66, and 63 dB for the first three formant resonances of avocal tract with uniform cross-sectional area. The analogvocaltract can be used with auditory processors in a feedback speechlocked loop—analogous to a phase lockedloop—to implementspeech recognition that ispotentially robust in noise. Our useof a physiological modelof the human vocal tract enables theanalog vocal tract chip to synthesize speech signals of interest,using articulatory parameters that are intrinsically compact andlinearly interpolatable.












Fig2:Schematic digram of transmission line vocal tract
















REFERENCES

[1] B. Raj, L. Turicchia, B. Schmidt-Nielsen, and R. Sarpeshkar, “An FFTbased
companding front end for noise-robust automatic speech recognition,”
EURASIP J. Audio, Speech, Music Process, vol. 2007, 2007,
10.1155/2007/65420, Article ID 65420.
[2] R. Sarpeshkar, M. W. Baker, C. D. Salthouse, J. Sit, L. Turicchia, and
S. M. Zhak, “An ultra-low-power programmable analog bionic ear processor,”
IEEE Trans. Biomed. Eng., vol. 52, no. 4, pp. 711–727, Apr.
2005.
[3] L. Turicchia and R. Sarpeshkar, “A bio-inspired companding strategy
for spectral enhancement,” IEEE Trans. Speech Audio Process., vol.
13, no. 2, pp. 243–253, Mar. 2005.
[4] C. G. Bell, H. Fujisaki, J. M. Heinz, K. N. Stevens, and A. S. House,
“Reduction of speech spectra by analysis by synthesis techniques,” J.
Acoust. Soc. Amer., vol. 33, pp. 1725–1736, 12. 1961.
[5] M. M. Sondhi and J. Schroeter, “A hybrid time-frequency domain articulatory
speech synthesizer,” IEEE Trans. Acoustics, Speech Signal
Process., vol. ASSP-35, no. 7, pp. 955–967, Jul. 1987.
[6] K. N. Stevens, S. Kasowski, and C. G. M. Fant, “An electrical analog
of the vocal tract,” J. Acoust. Soc. Amer., vol. 25, pp. 734–742, 1953.
[7] G. Rosen, “Dynamic analog speech synthesizer,” J. Acoust. Soc. Am.,
vol. 30, pp. 201–209, 1958.
[8] G. Kron, “Tensorial analysis and equivalent circuits of elastic structures,”
J. Franklin Instit., vol. 238, no. 6, pp. 399–442, 1944.
[9] R. Lyon and C. Mead, “An analog electronic cochlea,” IEEE Trans.
Acoustics, Speech Signal Process., vol. 36, no. 7, pp. 1119–1134, Jul.
1988.
[10] L. Watts, “Cochlear Mechanics: Analysis and Analog VLSI,” Ph.D.
dissertation, Calif. Instit., Pasadena, 1993.
[11] M. A. Mahowald and C. A. Mead, “Silicon retina,” in Analog VLSI and
Neural Systems, C. A. Mead, Ed. Reading, MA: Addison-Wesley,
1989, pp. 257–278.
[12] K. A. Boahen and A. G. Andreou, “A contrast sensitive silicon retina
with reciprocal synapses,” Adv. Neural Inf. Process. Syst. 4, pp.
764–772, 1992.
[13] E. A. Vittoz and X. Arreguit, “Linear networks based on transistors,”
Electron. Lett., pp. 297–299, Feb. 1993.
[14] R. Sarpeshkar, R. E. Lyon, and C. Mead, “A low-power wide-linearrange
transconductance amplifier,” Analog Integr. Circuits Signal
Process., vol. 13, pp. 123–151, 05. 1997.
[15] K. N. Stevens, Acoustic Phonetics. Cambridge, MA: MIT Press,
1998, vol. 30, p. 607.
[16] G. Fant, J. Liljencrants, and Q. Lin, “A four-parameter model of glottal
flow,” Speech Transmission Laboratory Quarterly Progress and Status
Report (STL-QPSR) no. 4, 1985.
[17] Y. Tsividis, OpBoston, MA: WCB/McGraw-Hill, 1998, p. 620.
[18] B. Gilbert, “Translinear circuits: A proposed classification,” Electron.
Lett., vol. 11, pp. 14–16, 1975.
[19] M. O’Halloran and R. Sarpeshkar, “A 10-nW 12-bit accurate analog
storage cell with 10-aA leakage,” IEEE J Solid-State Circuits, vol. 39,
no. 11, pp. 1985–1996, Nov. 2004eration and Modeling of the MOS Transi[20] K. H.Wee and R. Sarpeshkar, “An electronically tunable linear or nonlinear
MOS resistor,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 55,
no. 9, pp. 2573–2583, Oct. 2008.
[21] S. Maeda, “Compensatory articulation during speech: Evidence from
the analysis and synthesis of vocal-tract shapes using an articulatory
model,” in Speech Production and Speech Modelling,W. J. Hardcastle
and A. Marchal, Eds. Dordrecht, The Netherlands: Kluwer, 1990, pp.
131–149.
[22] L. R. Rabiner and B. H. Juang, Fundamentals of Speech Recognition.
Englewood Cliffs, NJ: Prentice-Hall, 1993, p. 507.
[23] J. Schroeter and M. M. Sondhi, “Techniques for estimating vocal-tract
shapes from the speech signal,” IEEE Trans. Speech Audio Process.,
vol. 2, no. 1, pp. 133–150, Jan. 1994.
[24] B. Gilbert, “Errata,” Electron. Lett., vol. 11, p. 136, 1975stor, 2nd ed.