System object: phased.SteppedFMWaveform
Samples of stepped FM pulse waveform
Y = step(sSFM)
Y = step(sSFM,prfidx)
Starting in R2016b, instead of using the
Y = step(sSFM) returns samples of the stepped
FM pulses in a column vector,
Y. The output,
results from increasing the frequency of the preceding output by an
amount specified by the
If the total frequency increase is larger than the value specified
SweepBandwidth property, the samples of
a rectangular pulse are returned.
Y = step(sSFM,prfidx), uses the
to select the PRF from the predefined vector of values specified by
PRF property. This syntax applies when
you set the
PRFSelectionInputPort property to
The object performs an initialization the first time the
Create a stepped frequency pulse waveform object with a frequency step of 40 kHz and four frequency steps.
waveform = phased.SteppedFMWaveform(... 'NumSteps',4,'FrequencyStep',40e3,... 'OutputFormat','Pulses','NumPulses',1); fs = waveform.SampleRate;
waveform method to obtain the pulses.
First, generate pulse 1.
pulse1 = waveform();
Then, generate pulse 2, incremented by the frequency step 40 kHz
pulse2 = waveform();
Next, generate pulse 3, incremented by the frequency step 40 kHz
pulse3 = waveform();
Finally, generate pulse 4, incremented by the frequency step 40 kHz
pulse4 = waveform(); nsamps = size(pulse4,1); t = [0:(nsamps-1)]/fs*1e6; plot(t,real(pulse4)) xlabel('Time (\mu sec)') ylabel('Amplitude') grid
In a stepped FM waveform, a group of pulses together sweep a certain bandwidth. Each pulse in this group occupies a given center frequency and these center frequencies are uniformly located within the total bandwidth.