Sinc function

The sinc function, also known as the interpolation function or filtering function, is the product of a sine function and a monotonically decreasing function. It is defined by:

${\displaystyle sinc\left(x\right)={\frac {sin\left(x\right)}{x}}}$

or:

${\displaystyle sinc\left(x\right)={\frac {sin\left(\pi x\right)}{\pi x}}}$

The sinc function oscillates with decreasing amplitude. Applications of the sinc function are found in communication theory, control theory, and optics.

See also: trigonometric function