Signals and Systems MATLAB project

ECE 351 Signal and System Project

This project gives students an opportunity of applying the knowledge they learn from ECE351 in radar signal processing. The Level I time-series (I&Q) data records the returned Electrical Magnetic energy in time domain. The I&Q data from each radar gate is a complex number, where “I” represents the in-phase component, and “Q” represents the quadrature components. Students are required to calculate and plot the following items:

Requirements:

1.) Calculating the basic radar parameter of Reflectivity (Z) in dB from time and frequency domains. The Reflectivity could be calculated as the total power return.

2.) Plotting and comparing the estimated Reflectivity (from time and frequency domain) using matlab command “pcolor”. Some helps related “pcolor” could be found in the following part. Note: the calculated reflectivity is in Polar coordination, and you should convert it into Cartesian coordination first before plot it.

3.) For the I&Q data from gate A (76, 157), plotting its I & Q components, real and imaginary parts of the Fourier Transform, magnitude and phase of the Fourier Transform.

4.) For the I&Q data from gate B (79, 159), plotting its I & Q components, real and imaginary parts of the Fourier Transform, magnitude and phase of the Fourier Transform.

5.) Calculating and plotting the Power Spectral Density from gates A and B (in dB). Gate A data is from non-tornadic region, and B is from tornadic region. Comparing their PSD, what kind of information you could find, and think about why?

6.) Label (x-axis, and y-axis) of each your plot.

Data Structure:

After loading the data with commands “load ‘data.mat’ ”, you will get a structure data with the following components:

data.TS

data.Range

data.Azimuth

where “TS” is level I time-series data, “Range” is the distance from each gate (‘pixel’) to radar, and “Azimuth” is the azimuthal angle from each gate (‘pixel’) according to North.

The dimension of Range is [1, 468], and dimension of Azimuth is [1, 241], respectively. The unit of Range is “km”, and unit of Azimuth is “deg.”

The dimension of TS is [241, 468, 32]. This indicates that at each azimuthal angle and range, there are 32 pulses radar data.

Note: the azimuthal angle is from 330o to 90o, the angular resolution is 0.5 o. Therefore, there are total 241 azimuthal angles.

Matlab code (help):

1.) Convert from Polar to Cartesian coordination:

XPLOT = sin(Azimuth*pi/180)’*Range;

YPLOT = cos(Azimuth*pi/180)’*Range;

2.) Pcolor command:

figure;

Pcolor(XPLOT, YPLOT, Ref_time);

shading flat;

caxis([0 50]);

axis image;

3.) Plot command:

figure;

plot(PSD_tornadic, ‘r-’,’LineWidth’,3);

axis([0 40 -40 20])

Other Helps:

1.) Matlab: e.g. type “help plot”

2.) Google

3.) My office hour is every hour as long as my door is open.

Example results