design_fir_gaussian_telecom

Coefficients for FIR approximation of a Gaussian filter, for a GFSK modulation.

Namespace: dsp::filter

Prototype

Vecf design_fir_gaussian_telecom(int n, float BT, int osf)

Parameters

nNumber of taps.
BTBandwidth - time product.
osfOversampling factor (ratio of sampling frequency versus symbol frequency).

Returns

Vector with filter coefficients.

Description

Computes the convolution of Gaussian filter and a moving average filter, with depth equal to the over-sampling factor. The standard deviation of the Gaussian filter is computed according to the Bandwidth-Time product (BT parameter).

This function is targeted for the design of a shaping filter for GFSK modulation.

Example


  soit n = 4;
  Vecf h[n];
  vector<float> BT = {0.3, 0.5, 0.8, 2.0};

  for(auto k = 0; k < n; k++)
    h[k] = design_rif_gaussien_telecom(21, BT[k], 5); // OSF = 5


  Figures f;
  f.subplot().plot(h[1], "|ob", "BT = 0,5");
  f.subplot().plot(h[2], "|og", "BT = 0,8");
  f.subplot().plot(h[3], "|om", "BT = 2,0");

See also

design_fir_gaussian()