 The cutoff frequency decreases as the radial propagation delay within a layer , relative to propagation delay between the layers, increases, introducing an upper limit on temporal resolution.
<fluency>  The cutoff frequency decreases as the radial propagation delay within a layer , relative to propagation delay between the layers, increases, introducing an upper limit on temporal resolution.
 The cut-off frequency decreases as the radial propagation delay within a layer , relative to propagation delay between the layers, increases, introducing an upper limit on temporal resolution.