Method and system for noise suppression
Aspects of the invention are directed towards a system and method for noise suppression. One or more embodiments of the invention describe the method comprising steps of receiving noise by a microphone and deriving a noise signal from the noise, the noise produced by a fan of a fire/smoke detection unit while drawing air and detecting the speed of the fan of the fire/smoke detection unit. The method further describes steps of amplifying the noise signal by the amplifier received from the microphone and producing an anti-phase noise signal by shifting a phase of the amplified noise signal received from the amplifier wherein the anti-phase noise signal is dependent on the detected speed of the fan. The method further describes steps of outputting the anti-phase noise signal through a speaker to suppress the noise produced by the fan of the fire/smoke detection unit while drawing the air.
1. A system comprising:
a fire/smoke detection unit comprising:
a fan adapted to draw air through a conduit, the fan producing a noise while drawing the air; and
a noise cancellation unit communicably coupled with the fire/smoke detection unit, the noise cancellation unit comprising:
a microphone adapted to receive the noise of the fan and deriving a noise signal from the noise;
a speed detection unit to detect a speed of the fan;
an amplifier adapted to amplify the noise signal received from the microphone;
a phase-shift unit adapted to shift a phase of the amplified noise signal received from the amplifier to produce an anti-phase noise signal, wherein the anti-phase noise signal is dependent on the detected speed of the fan; and
a speaker adapted to output the anti-phase noise signal received from the phase-shift unit;
wherein an amplitude of the anti-phase noise signal is based on the speed of the fan, wherein the speed of the fan is mapped to the amplitude of the anti-phase noise signal in decibels (dB).
2. The system of claim 1 , wherein the anti-phase noise signal suppresses the noise produced by the fan of the fire/smoke detection unit.
3. The system of claim 1 , wherein the noise signal and the anti-phase noise signal are at 180 degree of phase shift with respect to each other.
4. The system of claim 1 , wherein the amplifier amplifies the noise signal based on a threshold value required to suppress the noise produced by the fan.
5. The system of claim 1 , wherein the microphone and the fan are located in proximity with each other.
6. The system of claim 1 , wherein the speaker and the fan are located in proximity with each other.
7. The system of claim 1 , wherein the noise cancellation unit comprises a power amplifier to amplify the anti-phase noise signal produced by the phase-shift unit.
8. The system of claim 1 , wherein the fire/smoke detection unit is placed inside a premises.
9. The system of claim 1 , wherein the speed of the fan is mapped with the frequency of the anti-phase noise signal.
10. A method comprising:
receiving a noise by a microphone and deriving a noise signal from the noise, the noise produced by a fan of a fire/smoke detection unit while drawing air;
detecting a speed of the fan of the fire/smoke detection unit;
amplifying the noise signal by the amplifier received from the microphone;
producing an anti-phase noise signal by shifting a phase of the amplified noise signal received from the amplifier wherein the anti-phase noise signal is dependent on the detected speed of the fan; and
outputting the anti-phase noise signal through a speaker;
wherein an amplitude of the anti-phase noise signal is based on the speed of the fan,
wherein the speed of the fan is mapped to the amplitude of the anti-phase noise signal in decibels (dB).
11. The method of claim 10 , wherein the anti-phase noise signal suppresses the noise produced by the fan of the fire/smoke detection unit.
12. The method of claim 10 , wherein the noise signal and the anti-phase noise signal are at 180 degree of phase shift with respect to each other.
13. The method of claim 10 , wherein the amplifier amplifies the noise signal based on a threshold value required to suppress the noise produced by the fan.
14. The method of claim 10 , wherein the microphone and the fan are located in proximity with each other.
15. The method of claim 10 , wherein the speaker and the fan are located in proximity with each other.
16. The method of claim 10 , wherein the anti-phase noise signal produced by the phase-shift unit is amplified by a power amplifier.
17. The method of claim 10 wherein the fan draws air through a conduit coupled with the fire/smoke detection unit.