design_ema (1)

Transfert function of an exponential filter.


Prototype

static FRat<float> design_ema(Frequency fc)

Parameters

fc-3 dB normalized cut-off frequency.

Returns

Digital transfert function.

Description

This function returns the transfert function for the following system: \[ y_n = \gamma x_n + (1-\gamma) y_{n-1} \] That is: \[ H(z) = \frac{\gamma z}{z-(1-\gamma)} \] where \(\gamma\) is defined as a function of the desired cut-off frequency \(f_c\): \[ \gamma = 1 - e^{-2\pi f_c} \]

Example

See also

ema_coef()