Noise cancellation is a process of reducing or completely canceling out the unwanted sound, so that you can’t hear it. This technology is a growing field in acoustics. These days, modern lives are full of all sorts of noises; most of it is dangerous to our ears. This is mostly the case with people living in cities or major towns. They have very little quiet times during the day. The main aim of the Noise Cancellation Technology is find a cure for this excess noise that one experiences almost everyday.
Let us first looking at the working principle of Noise Cancellation Technology. A sound travel through air or water in the form of waves and each wave comes with a particular frequency, shape and size. Microphones can detect these sound waves in any given environment. Then a digital signal processor is incorporated in the system, which distinguishes the wanted and unwanted sound waves. This signal processor also determines what frequency of sound wave has to be generated for offsetting the unwanted one. Then the necessary offsetting sound wave is created and amplified by using headphones or speakers. Then the unwanted sound wave is canceled by this newly created sound wave. Thus the original sound signal comes out clear and fine with least amount of noise, in short, noise is reduced to a great extent.
One major noise cancellation device is the unique noise reduction headphones that are readily available in the market today. People working near the factories and airports can wear these headphones and save their eardrums from the loud noises around. It is preferred because it comes with a simple circuitry system and has a shorter wavelength.
These noise cancellation headphones also have some limitations. Firstly, they consume a lot of power, which is usually supplied by a battery that needs to removed and recharged on regular basis. They may not be able to completely cancel all sounds effectively. This is because a low frequency pressure wave might distort the signal. At higher frequencies they are less effective.
In fact, noise cancellation is a process of removing the unsuitable sound waves on a real-time basis. However this is easy for a single frequency sound wave than a multiple frequency one. Furthermore, apart from the noise reducing headphones, process is on to develop more such devices that can effectively help in saving one’s ear drums from being subject to undesirable sounds.