Have you heard of active noise cancellation?

MangoTree

Have you heard of active noise cancellation? [Copy link]

Suddenly, a melodious and ethereal singing voice came from the silent sea, which seemed to be far away and close, as if it was going to jump out from the bottom of the sea and drill into everyone's heart. Suddenly, the tone rose sharply and became a monotonous frequency. It was extremely harsh and hit the eardrum directly, and everyone was dizzy. "No! Cover your ears quickly! If we continue, we will all die!" The captain immediately covered his ears and yelled to the crew. The crew also covered their ears one after another.

And then... Everyone looked at each other. Their ears were tightly covered. The harsh sound was reduced a lot, but what was the captain saying with his mouth opening and closing? It was also inaudible!

(The picture comes from the Internet, please delete if it infringes)

The captain and all the crew members thought:

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This story tells us that sound insulation is the most common passive noise control method. Passive sound insulation will block effective sound while blocking noise. Although it can effectively isolate the noise source, it also isolates all external sounds.

At this time, some friends must be wondering:

Is it possible to communicate with people around me while isolating the noise?

The editor answers you: Of course!

Our friends at MangoTreedeveloped and improved the following technology as early as last year:Active Noise Reduction Technology.

MangoTree active noise reduction technology is mainly based onFPGA as the coreprocessor.

The processing performance isCPU 6 times. The front end of FPGA acquisition obtains the noise model by microphone, and converts the noise signal into a digital signal through the AD module. After obtaining the signal, FPGA performs a series of processing: filtering, signal analysis, automatic calibration, and finally the model generation module generates a signal to excite the speaker. After passing through the DA module, the speaker is controlled to complete the noise reduction function. The CPU is responsible for controlling the interface, FPGA parameter configuration and data storage. Active noise reduction can block huge noise while sensing small sounds, without affecting communication, because the technology of active noise reduction is relatively difficult. Currently used in the military,0pt] Airports and other occasions.

(Pictures from the Internet, please delete if infringed)

The principle of active noise reduction is not complicated. After collecting the noise sound wave information, the directional sound wave is calculated and played to offset the external noise. The difficulty lies in: it involves the design of algorithms, processors, and internal circuits, and is closely related to the actual environment sampling.

Because the reverse sound waves broadcast are superimposed on the useful sound waves, if there is a certain delay between the reverse sound waves and the external sound waves, the noise we hear will be more serious, and some frequency bands may also be offset.

The ground crew brother who became popular on a certain audio platform some time ago was wearing active noise reduction headphones.

Next are the friends who love shooting. When you go to the shooting range, you will also be asked to wear a pair of active noise reduction headphones.

In the field of active noise reduction, it is not limited to headphones.

In the automotive field, active noise reduction technology can also be applied.

We can continuously receive engine information through the management system and use this information to calibrate the noise level.

Management System

The car's audio system then generates an acoustic signal that is the opposite of the noise, which cancels out the noise and significantly reduces unnecessary engine noise.

The microphone in the cabin detects the noise. The sound level provides a basis for adjustment of the management system.

All of this is done automatically and continuously

MangoTreeeActive noise reduction technology can reduce reliance on traditional noise reduction methods. It allows manufacturers to make lighter and more efficient vehicles while improving the sound and recognition of the sound system.

All for a better driving experience.

In fact, active noise reduction technology is not far from our daily life.

Vacuum cleaners, sweeping robots, air purifiers, multi-function food processors, air conditioners and other refrigeration equipment, etc. Although the noise of these household appliances must meet national standards before they can be marketed, in this "silent era" where even a small fan requires low noise, our ultimate goal is of course to reduce the noise to the lowest possible level.0pt]The principle of active noise reduction is not complicated. After collecting the noise sound wave information, the directional sound wave is calculated and played to cancel the external noise. The difficulty lies in: it involves the design of algorithms, processors, and internal circuits, and is closely related to the actual environment sampling.

Because the reverse sound waves broadcast are superimposed on the useful sound waves, if there is a certain delay between the reverse sound waves and the external sound waves, then the noise we hear will be more serious, and some frequency bands may also be canceled.

The ground staff brother who became popular on a certain audio platform some time ago was wearing active noise-cancelling headphones.

Next are friends who love shooting. When you go to the shooting range, you will also be required to wear a pair of active noise reduction headphones.

In the field of active noise reduction, it is not just limited to headphones.

In the automotive field, active noise reduction technology can also be applied.

We can use the management system to continuously receive information from the engine and use this information to calibrate the noise level.

Management System

The car audio system then generates an acoustic signal that is opposite to the noise, which cancels out the noise, thereby significantly reducing unnecessary engine noise.

A microphone in the cabin detects noise levels and provides a basis for adjustments to the management system.

All of this is done automatically and continuously

MangoTreeeActive noise reduction technology can reduce reliance on traditional noise reduction methods. It allows manufacturers to make lighter and more efficient vehicles while improving the sound and recognition of the audio system.

All for a better driving experience.

In fact, active noise reduction technology is not far from our daily life.

Vacuum cleaners, sweeping robots, air purifiers, multi-function food processors, air conditioners and other refrigeration equipment. Although the noise of these household appliances must meet national standards before they can be allowed to be listed, in this "silent era" where even buying a small fan requires a low sound, our ultimate goal is of course to reduce the noise to the lowest possible level.

0pt]The principle of active noise reduction is not complicated. After collecting the noise sound wave information, the directional sound wave is calculated and played to cancel the external noise. The difficulty lies in: it involves the design of algorithms, processors, and internal circuits, and is closely related to the actual environment sampling.

Because the reverse sound waves broadcast are superimposed on the useful sound waves, if there is a certain delay between the reverse sound waves and the external sound waves, then the noise we hear will be more serious, and some frequency bands may also be canceled.

The ground staff brother who became popular on a certain audio platform some time ago was wearing active noise-cancelling headphones.

Next are friends who love shooting. When you go to the shooting range, you will also be required to wear a pair of active noise reduction headphones.

In the field of active noise reduction, it is not just limited to headphones.

In the automotive field, active noise reduction technology can also be applied.

We can use the management system to continuously receive information from the engine and use this information to calibrate the noise level.

Management System

The car audio system then generates an acoustic signal that is opposite to the noise, which cancels out the noise, thereby significantly reducing unnecessary engine noise.

A microphone in the cabin detects noise levels and provides a basis for adjustments to the management system.

All of this is done automatically and continuously

MangoTreeeActive noise reduction technology can reduce reliance on traditional noise reduction methods. It allows manufacturers to make lighter and more efficient vehicles while improving the sound and recognition of the audio system.

All for a better driving experience.

In fact, active noise reduction technology is not far from our daily life.

Vacuum cleaners, sweeping robots, air purifiers, multi-function food processors, air conditioners and other refrigeration equipment. Although the noise of these household appliances must meet national standards before they can be allowed to be listed, in this "silent era" where even buying a small fan requires a low sound, our ultimate goal is of course to reduce the noise to the lowest possible level.

0pt]Next are friends who love shooting. When you go to the shooting range, you will also be asked to wear a pair of active noise reduction headphones.

In the field of active noise reduction, it is not limited to headphones.

In the automotive field, active noise reduction technology can also be applied.

We can continuously receive engine information through the management system and use this information to calibrate the noise level.

Management System

The car's audio system then generates an acoustic signal that is the opposite of the noise, which cancels out the noise and significantly reduces unnecessary engine noise.

The microphone in the cabin detects the noise. The sound level provides a basis for adjustment of the management system.

All of this is done automatically and continuously

MangoTreeeActive noise reduction technology can reduce reliance on traditional noise reduction methods. It allows manufacturers to make lighter and more efficient vehicles while improving the sound and recognition of the sound system.

All for a better driving experience.

In fact, active noise reduction technology is not far from our daily life.

Vacuum cleaners, sweeping robots, air purifiers, multi-function food processors, air conditioners and other refrigeration equipment, etc. Although the noise of these household appliances must meet national standards before they can be marketed, in this "silent era" where even a small fan requires low noise, our ultimate goal is of course to reduce the noise to the lowest possible level.0pt]Next are friends who love shooting. When you go to the shooting range, you will also be asked to wear a pair of active noise reduction headphones.

In the field of active noise reduction, it is not limited to headphones.

In the automotive field, active noise reduction technology can also be applied.

We can continuously receive engine information through the management system and use this information to calibrate the noise level.

Management System

The car's audio system then generates an acoustic signal that is the opposite of the noise, which cancels out the noise and significantly reduces unnecessary engine noise.

The microphone in the cabin detects the noise. The sound level provides a basis for adjustment of the management system.

All of this is done automatically and continuously

MangoTreeeActive noise reduction technology can reduce reliance on traditional noise reduction methods. It allows manufacturers to make lighter and more efficient vehicles while improving the sound and recognition of the sound system.

All for a better driving experience.

In fact, active noise reduction technology is not far from our daily life.

Vacuum cleaners, sweeping robots, air purifiers, multi-function food processors, air conditioners and other refrigeration equipment, etc. Although the noise of these household appliances must meet national standards before they can be marketed, in this "silent era" where even a small fan requires low noise, our ultimate goal is of course to reduce the noise to the lowest possible level.0pt]Active noise reduction technology can reduce reliance on traditional noise reduction methods. It allows manufacturers to make lighter and more efficient vehicles while improving the sound and sound system's recognition.

All for a better driving experience.

In fact, active noise reduction technology is not far from our daily life.

Vacuum cleaners, sweeping robots, air purifiers, multi-function food processors, air conditioners and other refrigeration equipment, etc. Although the noise of these household appliances must meet national standards before they can be marketed, in this "silent era" where even a small fan requires low noise, our ultimate goal is of course to reduce the noise to the lowest possible level.0pt]Active noise reduction technology can reduce reliance on traditional noise reduction methods. It allows manufacturers to make lighter and more efficient vehicles while improving the sound and sound system's recognition.

All for a better driving experience.

In fact, active noise reduction technology is not far from our daily life.

Vacuum cleaners, sweeping robots, air purifiers, multi-function food processors, air conditioners and other refrigeration equipment, etc. Although the noise of these household appliances must meet national standards before they can be marketed, in this "silent era" where even a small fan requires low noise, our ultimate goal is of course to reduce the noise to the lowest possible level.