1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
A superdirective array of phase shift sources
Rent:
Rent this article for
USD
10.1121/1.4733556
/content/asa/journal/jasa/132/2/10.1121/1.4733556
http://aip.metastore.ingenta.com/content/asa/journal/jasa/132/2/10.1121/1.4733556
View: Figures

Figures

Image of FIG. 1.
FIG. 1.

Geometric arrangement for monopole simulations of and endfire array. Black points represent the microphones in the dark region. The open circle represents the microphone defining the bright zone in this case and the black stars represent the eight sources of the array.

Image of FIG. 2.
FIG. 2.

Comparison of acoustic contrast and array effort produced by an eight source endfire array, controlled by delay and sum and by the superdirective technique. The contrast that could be theoretically obtained without any array effort (AE) limitations and the result when the normalized array effort is limited to 6 dB at each frequency are also shown.

Image of FIG. 3.
FIG. 3.

Geometric arrangement for single row (upper plot) and double row (lower plot) simulations of broadside arrays. Black points represent the microphones in the dark zone. The open circle represents the bright zone microphone and the black stars represent the sources of the array.

Image of FIG. 4.
FIG. 4.

Comparison of acoustic contrast and array effort produced by the two double monopole arrays and for the array of point monopole and point hypercardioid sources. Results obtained with unconstrained array effort.

Image of FIG. 5.
FIG. 5.

Comparison of acoustic contrast and array effort produced by the two double monopole arrays and for the array of point monopole and point hypercardioid sources. Array effort limited to 6 dB using a frequency-dependent regularization parameter.

Image of FIG. 6.
FIG. 6.

Simplified diagram and low frequency-equivalent circuit of a phase shift loudspeaker.

Image of FIG. 7.
FIG. 7.

(Color online) View of the phase shift loudspeaker (upper plot) and its measured directivity indices (lower plot).

Image of FIG. 8.
FIG. 8.

Measured vertical (dashed line) and horizontal (solid line) directivity patterns for one of the phase shift sources at different frequencies.

Image of FIG. 9.
FIG. 9.

(Color online) Set-up of the measurements in the anechoic chamber (upper plot). The control zone used for the measurements in the anechoic chamber (lower plot) is also shown, where the open circles represents the microphones defining the bright zone, the black dots represent the dark zone microphones, and the black stars represent the eight sources of the array (scaled).

Image of FIG. 10.
FIG. 10.

Comparison of acoustic contrast and array effort between simulations and measurements. Results for the acoustic contrast maximization algorithm with the array effort limited to be lower than 6 dB.

Image of FIG. 11.
FIG. 11.

Measured directivity patterns of the array at different frequencies (solid lines) together with the directivity simulated using hypercardioid point sources (dotted lines). The upper plots show the results of using acoustic contrast maximization results and the lower plots show the least squares results. Array effort limited to be lower than 6 dB.

Image of FIG. 12.
FIG. 12.

Comparison of the measured acoustic contrast and array effort performance achieved by the two superdirective approaches operating in real-time.

Image of FIG. 13.
FIG. 13.

Impulse responses of the filter correspondent to the array’s fourth for least squares method (upper plot) and acoustic contrast maximization (lower plot).

Loading

Article metrics loading...

/content/asa/journal/jasa/132/2/10.1121/1.4733556
2012-08-08
2014-04-24
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: A superdirective array of phase shift sources
http://aip.metastore.ingenta.com/content/asa/journal/jasa/132/2/10.1121/1.4733556
10.1121/1.4733556
SEARCH_EXPAND_ITEM