gen.py 文件源码

def radial_filter(order, freq, array_configuration, amp_maxdB=40):
    """Generate modal radial filter of specified order and frequency

    Parameters
    ----------
    order : array_like
       order of filter
    freq : array_like
       Frequency of modal filter
    array_configuration : ArrayConfiguration
       List/Tuple/ArrayConfiguration, see io.ArrayConfiguration
    amp_maxdB : int, optional
       Maximum modal amplification limit in dB [Default: 40]

    Returns
    -------
    dn : array_like
       Vector of modal frequency domain filter of shape [nOrders x nFreq]
    """
    array_configuration = ArrayConfiguration(*array_configuration)

    extrapolation_coeffs = array_extrapolation(order, freq, array_configuration)
    extrapolation_coeffs[extrapolation_coeffs == 0] = 1e-12

    a_max = 10 ** (amp_maxdB / 20)
    limiting_factor = 2 * a_max / _np.pi * _np.abs(extrapolation_coeffs) * _np.arctan(_np.pi / (2 * a_max * _np.abs(extrapolation_coeffs)))

    return limiting_factor / extrapolation_coeffs