Radar Target Generation and Tracking
This project is for target generation and tracking using Frequency-modulated continuous-wave radar
- calculate the beat signal to find the Range and Doppler Effect.
- Apply FFT on the Beat Signal to express the signal in Frequency Dimension
- Apply CA-CFAR to avoid False Alarms by varying the Detection-Threshold of Range Doppler Map according to the noise-level.
The main idea of this step is to slice a window along the Range-Doppler Map such that a CUT is thresholded whilst taking margin for lagging cells and leading cells.
- Create a matrix of same size as RDM to store the filtered/thresholded values
[x,y] = size(RDM);
RDM_Filtered = zeros(x,y);
- Make a loop for Range-Dimesion which starts after particular marging
for R = Tr + Gr + 1 : Nr/2 - (Tr+Gr)
- Make another loop for Doppler-Dimension where a margin is considered at start
for D = Td + Gd + 1 : Nd - (Td+Gd)
- Define Window-Size of which we iterate over the Map
range_start = R - Tr - Gr; range_end = R + Tr + Gr;
doppler_start = D - Td - Gd; doppler_end = D + Td + Gd;
- Iterate the Window and Calculate the noise of included cells, take average and specify threshold
guard = RDM(R - Gr : R + Gr, D - Gd : D + Gd);
cells = RDM(range_start : range_end,doppler_start : doppler_end);
training = setdiff(cells, guard);
noise_level = db2pow(training);
average_noise = sum(noise_level) / ntrain;
db = pow2db(average_noise);
threshold = db + offset;
- Check for threshold value for CUT, if pass = 1;
if RDM(R, D) > threshold
RDM_Filtered(R, D) = 1;
end
Cells have been selected on both dimensions; Range and Doppler
- Range Dimension
Tr = 10;
Td = 5;
- Doppler Dimension
Gr = 5;
Gd = 1;
- Set offset Value
offset = 20;
- Calculate the Total Training Cells for later use in the noise-average step
ntrain = (2*Tr+2*Gr+1)*(2*Td+2*Gd+1) - (2*Gr+1)*(2*Gd+1);
This was achieved by making a zero-matrix of same size as the RDM, theb only add value'1' to cells which pass the threshold value and satisfy the margin-indexing
This way, no noise was included throughout the process.
