We claim:
1. An active plus selective headset system which provides
active broadband attenuation of noise as well as adaptive speech
filtering, said system comprising:
- a headset means adapted to be worn by a user;
- reference sensing means on said headset means adapted to
sense speech and noise signals;
- speaker means on said headset means adapted to convey speech
signals to a user's ear; and
- controller means adapted to control the speaker means based
on input from the reference sensing means to provide active
broadband attenuation of all random inband noise as well as
adaptive speech filtering so that only the speech reaches the
ear, wherein said active broadband attenuation is accomplished
without synchronization pulses.
2. A system as in claim 1 wherein said headset means includes
residual microphone means located on said headset means and
including a feedback means connected to said speaker means.
3. A system as in claim 2 wherein said feedback means
includes an adaptive speech filter means and a cancellation
filter means.
4. A system as in claim 2 wherein said controller means is
run by an adaptive feedforward algorithm.
5. A system as in claim 2 wherein said headset means includes
an open backed muff.
6. A system as in claim 2 wherein said reference sensing
means is an electret microphone.
7. A system as in claim 6 wherein said headset system
comprises a pair of open backed muffs with the reference sensing
means located on the outside of said muffs.
8. An active plus selective headset system which provides
active broadband attenuation of noise as well as speech
filtering, said system comprising:
- a headset means adapted to be worn by a user, wherein said
headset means includes residual microphone means located on said
headset means and including a feedback means connected to said
speaker means that includes an adaptive speech filter means
adapted to filter speech from noise and a cancellation filter
means;
- reference sensing means on said headset means adapted to
sense speech, noise and warning signals;
- speaker means on said headset means adapted to convey speech
and warning signals to a user's ear; and
- controller means adapted to control the speaker means based
on input from the reference sensing means to provide active
broadband attenuation of noise as well as speech filtering so
that only the warning signals and speech reach the ear.
9. An active plus selective headset system which provides
active broadband attenuation of noise as well as speech
filtering, said system comprising:
- a headset means adapted to be worn by a user, wherein said
headset means includes residual microphone means located on said
headset means and including a feedback means connected to said
speaker means that includes an adaptive speech filter means and a
cancellation filter means;
- reference sensing means on said headset means adapted to
sense speech, noise and warning signals:
- speaker means on said headset means adapted to convey speech
and warning signals to a user's ear; and
- controller means adapted to control the speaker means based
on input from the reference sensing means to provide active
broadband attenuation of noise as well as speech filtering so
that only the warning signals and speech reach the ear;
- wherein an output from said adaptive speech filtering means
is mixed with an output from said controller means and a
resulting signal passed to said speaker means.
10. An active plus selective headset system which provides
active broadband attenuation of noise as well as speech
filtering, said system comprising;
- a headset means adapted to be worn by a user, wherein said
headset means includes residual microphone means located on said
headset means and including a feedback means connected to said
speaker means that includes an adaptive speech filter means and a
cancellation filter means;
- reference sensing means on said headset means adapted to
sense speech, noise and warning signals;
- speaker means on said headset means adapted to convey speech
and warning signals to a user's ear; and
- controller means adapted to control the speaker means based
on input from the reference sensing means to provide active
broadband attenuation of noise as well as speech filtering so
that only the warning signals and speech reach the ear,
- wherein an output from said adaptive speech filtering means
is filtered by an impulse response of the cancellation means and
subtracted from a signal from the residual microphone so as not
to interfere with operation of said controller means.
11. A system as in claim 1 wherein said reference sensing
means is external of said speaker means on said headset means and
said controller means is adapted to employ a feedforward method
of noise cancellation.
12. A system as in claim 2 wherein said residual microphone
means is internal of said speaker means on said headset means and
said controller means is adapted to employ a feedback method of
noise cancellation.
13. A headset system for providing active broadband
attenuation of unwanted random inband noise, as well as adaptive
speech filtering, comprising:
- a pair of muffs, each of said muffs comprising:
-
- a reference microphone attached to an outside portion of said
muff for sensing speech signals and unwanted random inband noise
signals;
- a speaker located on an inside portion of said muff; and
- a controller attached to said reference microphone such that
said signals sensed by said reference microphone act as an input
to said controller; said controller producing an anti-noise
output at said speaker to eliminate said unwanted random inband
noise signals at a user's ear and removing noise from said speech
signal by adaptive speech filtering so that the speech signals
output to the user's ear is clearer, wherein said elimination of
said unwanted random inband noise signals is accomplished without
synchronization pulses.
14. A headset system as in claim 13, further comprising a
residual microphone attached to said speaker for sensing any
unwanted random inband noise near the user's ear and providing an
output to said controller so that the anti-noise output can be
adjusted to compensate for said unwanted random inband noise.
15. A headset system as in claim 13 wherein said controller
includes a feedback compensator connected to said speaker.
16. A headset system for providing active broadband
attenuation of unwanted noise, as well as speech filtering,
comprising:
- a pair of muffs, each of said muffs comprising:
-
- a reference microphone attached to an outside portion of said
muff for sensing speech signals, warning signals, and unwanted
noise signals;
- a speaker located on an inside portion of said muff; and
- a controller including a feedback compensator connected to
said speaker and attached to said reference microphone such that
said signals sensed by said reference microphone act as an input
to said controller; said controller producing an anti-noise
output at said speaker to eliminate said unwanted noise signal at
a user's ear and removing noise from said speech signal so that
the speech signals output to the user's ear is clearer.
- wherein said feedback compensator includes an adaptive speech
filter and a cancellation filter.
17. A headset system as in claim 13 wherein said controller
is operated based on an adaptive feedforward algorithm.
18. A headset system as in claim 13 wherein said reference
sensing microphone is an electret microphone.
19. A system as in claim 1 wherein the reference sensing
means is adapted to additionally sense warning signals, the
speaker means is adapted to convey speech and warning signals to
the user, and the controller means is adapted to provide active
broadband attenuation of noise as well as speech filtering so
that only the warning signals and speech reach the ear.
20. A headset system as in claim 13, wherein the reference
microphone additional senses warning signals.