Trouble understanding Angle doppler in an MATLAB Example.

In the raw received signal, the higest value seems to be at 45 degree azimuth, but in the filtered signal part, the highest value, i.e the target detection seems to be at 0 degree azimuth. As far as I know, this was filtered using an ADPCA Canceller.

But the target is still marked at 45 degree azimuth. Why is this? Why has the azimuth angle shifted?

And why even after negating the clutter and jammer interfernce, are there values present at points were the target is not present? Is it just due to the noise?

The matlab intro video example mentioned above is :- https://in.mathworks.com/videos/introduction-to-radar-system-design-with-matlab-and-simulink-1611561736356.html

Any help will be highly appreciated.

Answer 1

[Divyanshu]

Hi Pratik,

Please go through the following pointers for better understanding:

• The target position is detected at 45 degrees angle from the radar in case of raw recieved signal as well as filtered signal.
• The difference in the two plots mentioned in the question, is that in raw data the clutter and the jammer signal both have high energy because of noise hence it appears yellow.
• While in filtered data the energy of both jammer signal and the clutter becomes low due to filtering hence it appears blue.

Hope it helps.