Overlap add and overlap save method
overlap add and overlap save method is the traditional name for an efficient way to evaluate the
discrete convolution between a very long signal x[n] and a finite impulse response (FIR) filter h[n].
![y[n] = x[n] * h[n] \ \stackrel{\mathrm{def}}{=} \ \sum_{m=-\infty}^{\infty} h[m] \cdot x[n-m] = \sum_{m=1}^{M} h[m] \cdot x[n-m],\,](https://upload.wikimedia.org/math/4/4/3/4434f3c649773dd1bf1b155b6a55b2ff.png)
We divided x(n) into small sequences of equal lengths and convoluted with h(n). Depending on which method is used, decomposed y(n) for both OAM and OSM were calculated.
Though FFT yields faster results it cannot be used in practice as it requires the entire length of the input signal which isn't possible as it would introduce large delay and memory requirements of the system will also increase. Hence, OAM and OSM are preferred.
https://drive.google.com/drive/folders/0BwJUrR8ne7NkUk1ReW9JV3RHQW8
Used for real time signals
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