US 7,606,378 B2
Radio distortion processing
Joseph A Hinkle, Huntsville, Ala. (US); and David J Madaj, Ann Arbor, Mich. (US)
Assigned to Chrysler Group LLC, Auburn Hills, Mich. (US); and Siemens VDO Automotive Electronics Corp., Huntsville, Ala. (US)
Filed on Apr. 11, 2001, as Appl. No. 9/833,183.
Prior Publication US 2002/0150266 A1, Oct. 17, 2002
Int. Cl. H03G 3/00 (2006.01); H03G 9/00 (2006.01)
U.S. Cl. 381—107  [381/108; 381/55; 381/102] 15 Claims
OG exemplary drawing
 
1. An audio distortion processing system comprising:
a first processing unit that receives an audio signal from an audio source, wherein said first processing unit controls a plurality of parameters for said audio signal;
a power amplifier in electrical communication with said first processing unit for receiving an output signal of said first processing unit, said power amplifier selectively generating a clipping signal, said power amplifier adapted to be in communication with at least one speaker;
a second processing unit in electrical communication with said power amplifier and said first processing unit for receiving said clipping signal from said power amplifier and sending control signals to said first processing unit; and
a plurality of inputs in communication with said second processing unit, said plurality of inputs respectively indicating values of said plurality of parameters;
wherein said control signal initiates an incremental reduction in a level of a first narrowband parameter of said plurality of parameters until one of either said clipping signal recedes or a reduction limit of said first narrowband parameter is achieved and then incremental reduction in a level of a second wideband parameter of said plurality of parameters if a reduction limit of said first narrowband parameter is achieved and said clipping signal persists, thereby reducing distortion in said audio signal,
wherein said second processor determines that said level of said second wideband parameter has been reduced in response to said clipping signal before said second processor determines that said level of said first narrowband parameter has been reduced in response to said clipping signal, and
wherein said control signals initiate an incremental recovery of an original level of said second wideband parameter if said clipping signal is not detected and then an incremental recovery of an original level of said first narrowband parameter if said original level of said second wideband parameter is fully recovered and said clipping signal is not detected, wherein said incremental recovery of said original level of said second wideband parameter followed by said incremental recovery of said original level of said first narrowband parameter reduces a noticeable change in an audible output of the system caused by operations of said second processing unit.