AWR2243: peaks at the farthest ranges bin of 1D FFT

Hi Experts

When we try to run official mmw demo on AM2732+AWR2243 EVM, 

We find that when we are using below specific profile , there are peaks at the farthest ranges bin of 1D FFT which is not target.

profileCfg 0 76.26 3.9 3 71.86666667 0 0 8.02 1 512 7500 0 0 34

Can you pls tell what's the reason behind this peak？ 

Thanks

Ken