www.gusucode.com > phased 案例源码 matlab代码程序 > phased/DoubleTriangularSweepExample.m
%% Double Triangular Sweep % This example shows how to sample an FMCW waveform with a double % triangular sweep in which the two sweeps have different slopes. Then, % the example plots a spectrogram. %% % *Note:* This example runs only in R2016b or later. If you are using an earlier % release, replace each call to the function with the equivalent |step| % syntax. For example, replace |myObject(x)| with |step(myObject,x)|. %% % Create an FMCW waveform object for which the |SweepTime| and % |SweepBandwidth| properties are vectors of length two. For each period, % the waveform alternates between the pairs of corresponding sweep time and % bandwidth values. st = [1e-3 1.1e-3]; bw = [1e5 9e4]; waveform = phased.FMCWWaveform('SweepTime',st,... 'SweepBandwidth',bw,'SweepDirection','Triangle',... 'SweepInterval','Symmetric','SampleRate',2e5,... 'NumSweeps',4); %% % Compute samples from four sweeps (two periods). In a triangular sweep, % each period consists of an up sweep and down sweep. x = waveform(); %% % Plot the spectrogram. [S,F,T] = spectrogram(x,32,16,32,waveform.SampleRate); image(T,fftshift(F),fftshift(mag2db(abs(S)))) xlabel('Time (sec)') ylabel('Frequency (Hz)')