IWR1443BOOST: CFAR detection

I am running the out-of-box demo firmware on the IWR1443. I am using a software running on PC, and not demo visualizer, to process the data stream from the sensor.

Both people counting and area scanner labs are not supported on IWR1443. In any case, the point cloud data is sufficient, we can handle the detection and tracking on the PC.

I would like to evaluate the feasibility of using IWR1443 first before considering other devices.

In that case, 

CHT said:

1. Is CFAR applied to each doppler bin independently, where the peaks detected in each doppler bin are added to the detection output list? 

What do you mean by this? If you want to learn about the implementation of the CFAR algorithm, consider reviewing 

C:/ti/mmwave_sdk_03_05_00_04/packages/ti/datapath/dpc/dpu/cfarcaproc/docs/doxygen/html/index.html

which discusses how the Doppler CFAR runs on the HWA and the parameter set that governs it.

CHT said:

2. If the number of detections are over the maximum limit, how are the detections selected for pointcloud output? In my setup, the sensor is used to monitor persons in a room. If there are two persons walking in the room, say person1 and person2, person1 could have a large number of points detected on him and person2 very few points. When this happens, the number of points in the pointcloud are usually at the observed maximum limit (64). My guess is that when the number of detections have reached the maximum limit, the CFAR process stops, so part of person2's points are not extracted. Am I right on this? If so, can you give suggestions on how to enable a more balanced point spread between persons in the room?

In principle, I understand your logic, but I think you can increase the maximum number of points beyond 64. Where did you get that maximum of 64 from?

Best,

Nate

1. From the description of cfarCfg in SDK2.1 user guide, only range direction is supported for my device.  Which means CFAR is only done in range domain? Thus, for each dopplerIdx in the range-doppler heatmap, there would be zero of more CFAR detections. And all these detections would be added to the detection output list. Since my device is on SDK 2.1, I am inferring from the SDK2.1 demo document, C:/ti/mmwave_sdk_02_01_00_04/packages/ti/demo/xwr14xx/mmw/docs/doxygen/html/index.html. 

2. The number 64 is based on the pointcloud output I obtained using various configurations. I am not able to increase the number of points above 64.