As described in Figure 2-1, the implementation of the obstacle detection application example in the signal-processing chain consists of the following blocks implemented as DSP code executing on the C674x core in the AWR1843AOP.

• Range processing
  • For each antenna, 1D windowing, and 1D fast Fourier Transform (FFT)
  • Range processing is interleaved with the active chirp time of the frame
• Range-angle heat-map generation
  • Generate angle spectrum for each range bin using covariance beamforming or Capon beamforming.
  • Outputs Range-Elevation angle heat-map and Range-Azimuth angle heat-map.
• Object Detection
  • On each range-angle heat-map, search a single peak cross angle for each range bin, then apply one dimension CFAR check on the peak angle cross the neighboring range bins.
  • Take the union (or interception) of the two peak sets detected from the two range-angle heat-maps.
• Doppler estimation
  • For each detected range bin, estimate the Doppler output and apply non-coherent combination among all antennas. Find the peak index and used it as the Doppler index of the detected target.
  • Outputs the Range-Doppler output of this Doppler peak index and used later for angle estimation.
• Angle of arrival estimation
  • Calculate the two-dimensional angle spectrum using 2D FFT.
  • Single peak search on this two-dimensional angle spectrum and calculate azimuth and elevation angle associated with the peak location.
• Clustering
  • Perform DBSCAN-based clustering algorithm every fixed number of frames and report the results.
  • Output the number of clustering and properties like clustering center and size.

Figure 2-1 Block Diagram