IWR1443BOOST: Minimum Distance for Object Detection

Hi, Rupak:

Since we see some coupling around DC, so it will be hard to detect anything at first several range bins.   But I would say, you should be able to detect something after 5th range bin.  If range resolution is 4cm, then your minimum detection is around 10-20cm.    And hope you already know how to calculate your range resolution, which is c/(2e4*RF_bandwidth)).  I looked your configuration, your valid RF bandwidth is about 3.7G, and your range resolution is about 4cm.

Hope it helps!

Best,

Zigang

Will the first few bins have no data? Or will it be unreliable?

The first few bins have all the data as well. But the close in target reflection will be there together with the coupling signal. So it will be had to detect the close in or to estimate them reliably.

Best,
Zigang

Can it be made better by changing parameters in the config file?

Your chirp already have the smallest range resolution. I do not think change chirp configuration will make it better. Maybe you can calibrate out the coupling effect. But it is not very easy because the coupling may change over temperature.

Best,
Zigang

I know 4cm is the lowest resolution I can have, I just want to lower the minimum distance at which obstacles will be detected.

I do not think a different chirp configuration will help. What are the minimum distance you are looking at? What type of application it is?

Best,
Zigang

I want to detect obstacles from 3cm to 5m.

Usually for the product, you will have a cover or install the radar sensor behind the car bumper, you always see the reflection from the case or bumper which is at 2~3cm. It will be very hard to separate your 3cm target from your cover/bumper reflection.

I have a plastic cover over the radar, I don't see any reflections from it.

Do you see the coupling then? How do you know it is not the combination of coupling and cover reflection?

How do I check for the coupling?

I would look at range-Doppler 2D FFT output, i.e, From ADC raw data, do a 2D FFT over range and doppler and calculate power for each one and sum over different antenna, and plot them out.

By the way, if you have moving object, it can be easier to detect because the coupling and cover/bumper reflection are usually at zero Doppler Bin.