Efficient digital audio automatic gain control

Electrical audio signal processing systems and devices – Including amplitude or volume control – Automatic

Reexamination Certificate

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Details

C381S104000

Reexamination Certificate

active

07406178

ABSTRACT:
The present invention is a digital dynamic compression or automatic gain control (AGC) (10) adapted for use in high quality audio and hearing aids applications. An efficient digital AGC design employs two compact ROM-based tables (ROM_CSD, ROM_SPL) in addition to two comparators (COMP_A, COMP_B) and several registers (REG_A, REG_B, ADDR_A, ADDR_B). While one ROM stores the values of discrete input signal levels, the other contains gain codes based on a canonical signed digit (CSD) coding approach that leads to a very simple gain multiplier (20). In many cases an extremely compact table for gain values can be achieved by reusing a single small-size ROM that behaves like one that is several time larger. Two design examples are shown to expound the insights of the new digital AGC design. For the less-than-half-dB-gain-step cases only two adders are required for the multiplier whereas just three adders are needed in the situations with less than quarter-dB gain steps.

REFERENCES:
patent: 4623872 (1986-11-01), Rainer
patent: 4947133 (1990-08-01), Thomas
patent: 5262974 (1993-11-01), Hausman et al.
patent: 5463695 (1995-10-01), Werrbach
patent: 5471651 (1995-11-01), Wilson
patent: 5606625 (1997-02-01), Dallavalle et al.
patent: 5831880 (1998-11-01), Lee
patent: 5832097 (1998-11-01), Armstrong et al.
patent: 5838807 (1998-11-01), Andersson et al.
patent: 5882442 (1999-03-01), Caron et al.
patent: 5892834 (1999-04-01), Smart et al.
patent: 6498855 (2002-12-01), Kokkosoulis et al.

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