Figure 1.

Hypothetical modulation filterbank models. A, An equal resolution filter (constant filter bandwidth) preserves the power of the signal across all frequencies. B, The filter bandwidths of a proportional resolution filterbank scale with frequency. This scaling can augment the power of the incoming signals for higher frequencies as a consequence of the larger bandwidths. The filterbank models are shown for temporal modulations; however, an equivalent framework can also be applied for spectral modulations.