THE AMBIGUITY DIAGRAM |
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function [reference, convolution] = waveform3(pts, cycles) %
Pseudo-random phase-coded modulation:
% - waveform #3 is a
sequence of short pulses generated at random
rand('state', 0); % Reset the
random number generator (this way we get the same %
"random" sequence every time) x = rand(pts/cycles,1); base = round(x);
% A sequence
of length pts/dwell consisting of 0's or 1's chosen % at random reference = []; for i = 1:pts/cycles
reference = [reference; base(i)*ones(cycles,1)]; end % Reference
must be a length pts vector matchedir = reference; for i = 1:pts
matchedir(i) = reference(1 + pts - i); end % Matchedir
is the time-reversed version of reference sequence = .5*(ones(length(reference),1)) - .5*reference; frange = -5:0.01:5; convolution = []; for i = 1:length(frange) freq =
frange(i);
realsig = real(exp(j * 2 * pi * (sequence + (2 * freq * ([1:pts]') /
pts))));
imagsig = imag(exp(j * 2 * pi * (sequence + (2 * freq * ([1:pts]') / pts))));
% Break signal into real and imaginary components
realconv = conv(realsig, matchedir);
imagconv = conv(imagsig, matchedir);
% Convolve each part individually
convolution = [convolution, sqrt((realconv .* realconv) + (imagconv.*
imagconv))];
% Build the convolution vector end ^ back to top ^ |
MOTIVATION – Why this is important OBJECTIVE – What we hoped to achieve AMBIGUITY DIAGRAM - What it is AMBIGUITY DIAGRAM - How to read it WAVEFORMS – The signals we analyzed RESULTS – Results for CW and PCM CHIRP - A closer look POSSIBLE EXTENTIONS – What’s next CODE - Fascinating stuff ACKNOWLEDGMENTS - Who we have to thank |