Assignment -
For this problem, hand in a single figure with four panels (in a 2x2 configuration) and all of your code. Load the datafile PS04_ECG.mat. Variable ecg is an ECG signal in mV sampled at 500 Hz.
a) In the upper-left-hand panel, plot the ECG signal against time in seconds.
b) In the middle-left-hand panel, plot the magnitude of the discrete fourier transform (discrete time fourier series) of the ECG signal. Your x axis variable should be an index, m^. To keep the values matched for all fourier transforms, divide the magnitude for this problem by the signal length.
c) In the bottom-left-hand panel, plot the phase of the discrete fourier transform (discrete time fourier series) of the ECG signal over the same x axis range. Limit your y axis from -π to π.
d) In the bottom-right-hand panel, plot the phase of the discrete time fourier transform of the ECG signal. Your x axis variable should be normalized radian frequency, and limited from 0 to 2π.
e) In the middle-right-hand panel, plot the amplitude of the discrete time fourier transform of the ECG signal. Limit your x axis from -π to π.
f) In the upper-right-hand panel, plot the magnitude of the fourier transform (continuous fourier transform) of the ECG signal on logarithmic axes. Sum the amplitudes of the positive and negative frequency components and plot the sums of all non-zero-frequency components at their positive frequency value. Overlay text on the graph to identify the value at zero frequency.