# How to reduce spectral leakage?

We are looking at FMCW radar ADC signals and converting from the time domain to the frequency domain in order build a range doppler map but want to have the best signal to noise ratio possible.

In order to reduce spectral leakage, we are using the Hann function. It just seems to be accepted that we use the Hann function.

Are there any other functions that we should be considering?

• no, it's not "generally accepted that we use the Hann function". Choice of window depends on what you want to minimize (e.g. power in strongest sidelobe OR cumulative power out-of-band OR attenuation at $f\rightarrow \infty$ OR …). – Marcus Müller Jul 6 '17 at 13:21
• @MarcusMüller thanks. We're building a doppler range map. I've edited the question to reflect. – SeanJ Jul 6 '17 at 13:29
• A friend of mine wrote a paper on Range/velocity diagrams and windowing, can't think of the title. Look for papers by Stefan Wunsch! – Marcus Müller Jul 6 '17 at 13:30
• Improved detector for continuous wave radar waveforms exploiting phase information - sadly don't have an IEEE membership (\$33 for paper)! Is it the right article? – SeanJ Jul 6 '17 at 13:47
• @SeanJ A simple Google search of the author on that IEEE paper shows that he makes a preprint available: cel.kit.edu/download/Radarcon_2015_final_fonts_embedded.pdf – Peter K. Jul 6 '17 at 17:02