AWR1443BOOST: What is raw ADC data mathematically?

Part Number:AWR1443BOOST

Hello,

If I transmit one chirp, I will receive a raw ADC data of 256 samples. I think the 256 sampels are sampled from the IF signal Xout = sin[(w1-w2)*t + (theta1-theta2)]. However, no matter how many objects are detected, the number of ADC samples are always 256. For the detected objects in different range, multiple reflected signal are supposed to be received. Why do not the number of ADC samples change?

Thanks,

Yun