In range-Doppler processing, which windows are used to suppress sidelobes?

In range-Doppler processing, which windows are used to suppress sidelobes?

• A. Exponential and flat-top windows; applied in waveform synthesis.
• B. Hamming and rectangular windows; applied in range gating.
• C. Hanning and Blackman windows; applied in range-Doppler processing to suppress sidelobes.
• D. Blackman-Harris and Kaiser; applied in Doppler shift estimation.

Answer: (C)

Windowing the data before forming the range-Doppler spectrum helps prevent energy from strong reflectors from leaking into neighboring range and Doppler bins. The Hann (Hanning) window and the Blackman window are classic smoothing windows designed specifically to suppress sidelobes in the frequency domain. Applying them in the range–Doppler processing reduces sidelobe levels, making it easier to distinguish closely spaced targets. The trade-off is a bit of broadening of the main lobe, which slightly reduces resolution, but the gain in sidelobe suppression helps avoid false detections and improves target separation. Other windows listed have different primary purposes or trade-offs and are not as well suited for this particular goal in range-Doppler processing.

Windowing the data before forming the range-Doppler spectrum helps prevent energy from strong reflectors from leaking into neighboring range and Doppler bins. The Hann (Hanning) window and the Blackman window are classic smoothing windows designed specifically to suppress sidelobes in the frequency domain. Applying them in the range–Doppler processing reduces sidelobe levels, making it easier to distinguish closely spaced targets. The trade-off is a bit of broadening of the main lobe, which slightly reduces resolution, but the gain in sidelobe suppression helps avoid false detections and improves target separation. Other windows listed have different primary purposes or trade-offs and are not as well suited for this particular goal in range-Doppler processing.