Version 1.0
This tool simulates the directional and frequency responses of two-microphone endfire or broadside microphone arrays. This software tool may be best-used as an interactive companion to application note AN-1140: Microphone Array Beamforming. You can use this to simulate an array’s performance before building hardware and implementing the beamforming algorithm in a processor.
Requirements:
The Microphone Beamforming Array tool can be downloaded here:
Before the .exe can be run, you must either have Matlab installed on your PC or download and install the free Matlab Compiler Runtime (MCR). You can download the appropriate (Window 32- or 64-bit) MCR from the Mathworks site at http://www.mathworks.com/products/compiler/mcr/index.html. The beamforming64.zip and beamforming32.zip files both include an executable file and a readme.txt. The .exe can be unzipped and run directly; no installation is required.
This tool can simulate the response of a differential endfire array or a broadside summing array.
For an endfire array, there are four design parameters that affect the displayed responses.
For a broadside array, there are two design parameters that affect the displayed responses.
The frequency response plot has three controls to adjust what is displayed.
Checking this box will keep all currently-displayed polar and frequency responses and display new responses on top. This can be useful to display how the array’s directional response changes across the frequency range, or how the frequency response of the array changes with different incident angles. A new plot will be displayed after you enter a new value into one of the “Array Settings” fields. Up to five plots will be displayed with different line colors before the colors are re-used. The line colors are used in this order and cannot be changed: blue, red, green, cyan, magenta. After unchecking the “Hold Current Plot(s)” box, the color of the next plot will reset to blue.
Feel free to provide any feedback on this tool in the Audio community at Analog Devices EngineerZone. Further details on microphone array beamforming can be found in application note AN-1140.