5440642 : Analog noise cancellation system using digital optimizing of variable parameters
INVENTORS: Denenberg; Jeffrey N., Trumbull, CT 06611
Sabett; Randy V., Randallstown, MD 21133
ASSIGNEES: none
ISSUED: Aug. 8 , 1995   FILED: Sep. 20, 1993
SERIAL NUMBER: 123928   MAINT. STATUS:
INTL. CLASS (Ed.  6): H04R 25/00;
U.S. CLASS: 381-071; 381-094;
FIELD OF SEARCH: 381-71,94 ; 415-119 ; 67-136 ;
AGENTS: Hiney; James W.;

ABSTRACT:   A digitally controlled analog cancellation system containing an analog noise cancellation circuit with a residual microphone (39) with a digital virtual earth controller (40) for optimizing variable parameters employed in the analog cancellation circuit.

U.S. REFERENCES:   (No patents reference this one)
Patent No. Inventor Issued Title
4837832 Fanshel 6 /1989 Electronic hearing aid with gain control means for eliminating low frequency noise
5105377 Ziegler 4 /1992 Digital virtual earth active cancellation system
5140640 Groupe et al. 8 /1992 Noise cancellation system
5146505 Pfaff et al. 9 /1992 Method for actively attenuating engine generated noise
5216721 Melton 6 /1993 Multi-channel active acoustic attenuation system
5259033 Goodings et al. 11 /1993 Hearing aid having compensation for acoustic feedback
5321759 Yuan 6 /1994 Active noise control system for attenuating engine generated noise
5325437 Doi et al. 6 /1994 Apparatus for reducing noise in space applicable to vehicle compartment

EXEMPLARY CLAIM(s): Show all 9 claims

We claim:
  • 1. A hybrid noise cancellation system for canceling unwanted noise, said system comprising
    • a first noise canceling electronic means for canceling low frequency noise, and
    • a second noise canceling electronic means for canceling periodic noise,
    said first and second noise canceling means being connected and implemented in such a way that the second noise canceling means optimizes variable parameters employed in the first noise canceling means.

RELATED U.S. APPLICATIONS: none

FOREIGN APPLICATION PRIORITY DATA: none
FOREIGN REFERENCES: none
OTHER REFERENCES: none
PRIMARY/ASSISTANT EXAMINERS: Brinich; Stephen;
ADDED TO DATABASE: Aug. 23, 1996