Apparatus and methods for processing a signal using a fixed-point operation

A signal processing method comprising:

• receiving, at an input of a digital signal processor, a signal comprising a plurality of subbands and envelope information of the plurality of subbands, wherein the envelope information indicates a dynamic range of at least one of the plurality of subbands;
• processing, by each of a plurality of subband processors in the digital signal processor, a respective one of the plurality of subbands to provide a processed subband signal based on the envelope information of the one of the plurality of subbands to account for the dynamic range of the one of the plurality of subbands, wherein processing the one of the plurality of subbands comprises processing the one of the plurality of subbands based on an internal state of the one of the plurality of subband processors, the internal state computed based on previous values of the one of the plurality of subbands in accordance with a state-space model;
• and
• providing, by an output collector coupled to the plurality of subband processors, an output signal based on the processed subband signal from each of the plurality of subband processors.

A tangible, non-transitory computer readable medium including instructions operable to cause an apparatus to:

• receive a signal comprising a plurality of subbands and envelope information of the plurality of subbands, wherein the envelope information indicates a dynamic range of at least one of the plurality of subbands;
• process each of the plurality of subbands using the envelope information of the respective one of the plurality of subbands to provide a processed subband signal for the respective one of the plurality of subbands, wherein processing each of the plurality of subbands comprises processing the one of the plurality of subbands based on an internal state of the one of a plurality of subband processors, the internal state computed based on previous values of the one of the plurality of subbands in accordance with a state-space model;
• and
• provide an output signal by combining processed subband signals of the plurality of subbands.