Methods of fixed codebook searching for audio codecs

A method comprising:

• receiving, by an audio encoder, an audio signal comprising a plurality of subframes;
• selecting a first location for a first pulse of a first subframe of the plurality of subframes;
• determining k number of pulse candidates, wherein each pulse candidate comprises a plurality of pulse locations for the pulse of the first subframe;
• selecting a first location for a second pulse of the first subframe;
• determining, for each of the k number of first pulse candidates, l number of pulse locations for the first pulse and the second pulse, thereby resulting in m number of pulse candidates;
• selecting a desired pulse candidate from the m number of pulse candidates;
• and
• generating a FCB signal according to the selected desired pulse candidate.

A method comprising:

• receiving, by an audio encoder, an audio signal comprising a plurality of subframes;
• generating a plurality of pulse candidates, wherein each pulse candidate comprises a plurality of pulse locations for one or more pulses of the first subframe;
• determining a first pulse candidate of the plurality of pulse candidates comprises a signal signature value of a second pulse candidate of the plurality of pulse candidates;
• and
• removing either the first pulse candidate or the second pulse candidate from the plurality of pulse candidates.