The sine window, also known as half-sine window, is a classical windowing function that follows [[Princen-Bradley condition]] for the perfect reconstruction criteria. The sine window is defined as: $ w_{\sin}(n) = \begin{cases} \sin\left( \frac{n\pi}{N} \right), & 0\le n \lt N\\ \\ 0, & \text{otherwise} \end{cases} $ where $N$ is the window length. ![[Window_function_and_frequency_response_-_Cosine.svg]] [Wikimedia](https://en.wikipedia.org/wiki/File:Window_function_and_frequency_response_-_Cosine.svg)