##### Page tree
Go to start of banner

# Linear prediction

Speech is a continuous signal, which means that consecutive samples of the signal are correlated (see figure on the right). In particular, if we know a previous sample xn-1, we can make a prediction of the current sample, $$\hat x_n = x_{n-1},$$ such that $$\hat x_n \approx x_n.$$ By using more previous samples we have more information, which should help us make a better prediction. Specifically, we can define a predictor which uses M previous samples to predict the current sample xas
$\hat x_n = - \sum_{k=1}^M a_k x_{n-k}.$