def get_pixdist_ratio(m_size, ant_rad):
    """Get the ratio between pixel number and physical distance

    Returns the pixel-to-distance ratio (physical distance, in meters)

    Parameters
    ----------
    m_size : int
        The number of pixels used along one-dimension for the model
        (the model is assumed to be square)
    ant_rad : float
        The radius of the antenna trajectory during the scan, in meters

    Returns
    -------
    pix_to_dist_ratio : float
        The number of pixels per physical meter
    """

    # Get the ratio between pixel and physical length
    pix_to_dist_ratio = m_size / (2 * ant_rad)

    return pix_to_dist_ratio