I want to build a mic array. Can I use ADAU1467 for that?

Does ADAU1467 support in-built algorithms for noise cancellation, echo cancellation, beamforming which are required to build mic array?

  • 0
    •  Analog Employees 
    on Jun 14, 2021 1:53 PM

    Hello ,

    Sorry for the delayed response.

    Please note that up to four PDM microphones can be connected as audio inputs. Each pair of microphones can share a single data line; therefore, using four PDM microphones requires two GPIO pins. Any multipurpose pin can be used as a microphone data input, with up to two microphones connected to each pin. This configuration is set up using the corresponding MPx_MODE and DMIC_CTRLx registers.

    Please refer the DIGITAL PDM MICROPHONE INTERFACE (PageNo: 77 / 207) in the datasheet of ADAU146x.

    Modified FXLMS - This module implements the Modified Filtered-X LMS algorithm which is an adaptive FIR filter based on minimizing the least mean squared value of the error signal. The algorithm is applied to noise cancellation applications where it takes into account the fact that the point of cancellation is not at the anti-noise output speaker but at the position of the error microphone. The module provides a training mode which enables training and estimating the secondary paths between the output speakers and the error microphones as FIR filter coefficients. These coefficients are then used in the run-time mode of the module to take into account the paths and provide effective noise cancellation based on the reference inputs.

    The module can be found at the below location in the tree tool box:

    Refer Wiki Link: wiki.analog.com/.../mfxlms

    Acoustic Echo Cancellation - The Acoustic Echo Cancellation (AEC) block is designed to remove echoes, reverberation, and unwanted added sounds from a signal that passes through an acoustic space.
    Note: Licensed add-ins .

    Refer Wiki Link: wiki.analog.com/.../aec

    Unfortunately, there is no in-built algorithms for beamforming.


  • 0
    •  Analog Employees 
    on Jun 15, 2021 7:09 PM

    Hello ganeshhegde,

    There is actually a fixed beamformer that is available for two mics. You could build a project out of several different beams to choose which is the greatest. At the moment we do not have an adaptive one or one for multiple mics available in a standard block. 

    Here is where you find it:

    Dave T