Signal Processing Toolbox

gauspuls

Generate a Gaussian-modulated sinusoidal pulse

Syntax

• yi = gauspuls(t,fc,bw)
  yi = gauspuls(t,fc,bw,bwr)
  [yi,yq] = gauspuls(...)
  [yi,yq,ye] = gauspuls(...)
  tc = gauspuls('cutoff',fc,bw,bwr,tpe)
  

Description

gauspuls generates Gaussian-modulated sinusoidal pulses.

yi = gauspuls(t,fc,bw) returns a unity-amplitude Gaussian RF pulse at the times indicated in array t, with a center frequency fc in hertz and a fractional bandwidth bw, which must be greater than 0. The default value for fc is 1000 Hz and for bw is 0.5.

yi = gauspuls(t,fc,bw,bwr) returns a unity-amplitude Gaussian RF pulse with a fractional bandwidth of bw as measured at a level of bwr dB with respect to the normalized signal peak. The fractional bandwidth reference level bwr must be less than 0, because it indicates a reference level less than the peak (unity) envelope amplitude. The default value for bwr is -6 dB.

[yi,yq] = gauspuls(...) returns both the in-phase and quadrature pulses.

[yi,yq,ye] = gauspuls(...) returns the RF signal envelope.

tc = gauspuls('cutoff',fc,bw,bwr,tpe) returns the cutoff time tc (greater than or equal to 0) at which the trailing pulse envelope falls below tpe dB with respect to the peak envelope amplitude. The trailing pulse envelope level tpe must be less than 0, because it indicates a reference level less than the peak (unity) envelope amplitude. The default value for tpe is -60 dB.

Remarks

Default values are substituted for empty or omitted trailing input arguments.

Examples

Plot a 50 kHz Gaussian RF pulse with 60% bandwidth, sampled at a rate of 1 MHz. Truncate the pulse where the envelope falls 40 dB below the peak:

• tc = gauspuls('cutoff',50e3,0.6,[],-40); 
  t = -tc : 1e-6 : tc; 
  yi = gauspuls(t,50e3,0.6); 
  plot(t,yi)
  
  
  

See Also

chirp, cos, diric, pulstran, rectpuls, sawtooth, sin, sinc, square, tripuls

fvtool

gausswin