Question about X2M200 baseband data number of bins

Discussion in 'Respiration Sensor' started by Yunze, Aug 1, 2018.

  1. Yunze

    Yunze New Member

    Hi,

    I am trying to collect baseband ap data from X2M200 using python 2.7. I currently have two X2M200 sensors. One X2M200 is streaming out 52 bins data, but the other one is streaming out only 26 bins data. I have double checked the 'num_bins' in baseband_ap_data. One is showing 52 and the other is showing 26. Is there a way to change 'num_bins' in baseband_ap_data? Thanks.
     
  2. Aksel Johnsby

    Aksel Johnsby Moderator Staff Member

    Hi Yunze,

    The number of bins are determined by the detection zone range. If the range of your sensors are the same, the number of bins should be the same as well.

    Have a great day!
    --
    Aksel
     
  3. Yunze

    Yunze New Member

    Hi Aksel,

    I tried to change the detection zone range using set_detection_zone() function in Python. However, it does not change the number of bins. Below is raw data I have printed from these two sensors. You can see that these two X2M200 sensors also have different carrier_frequency and range_offset. The only difference between these two X2M200 is, one is running the original firmware and the other is running the recovered firmware per https://www.xethru.com/community/threads/x2m200-firmware-upgrade-issue.452/

    num_bins 52
    bin_length 0.0379774682224
    sample_frequency 39497105408.0
    carrier_frequency 7336198656.0
    range_offset 0.300000011921
    num_bins 26
    bin_length 0.037683416158
    sample_frequency 39805308928.0
    carrier_frequency 7190491136.0
    range_offset 0.40000000596
     
  4. NSANGOU CHOUAIBOU

    NSANGOU CHOUAIBOU Active Member

    Hi Yunze,
    Please check if the same profile (sleep or respiration) is set on both X2M200 sensors. These profiles have different radar frame length for the same range setting.

    B.R
     
  5. Yunze

    Yunze New Member

    Hi B.R,

    You are right. It is the profile issue. Sleep profile will set 52 bins and respiration profile will set 26 bins. However, it seems that set_detection_zone() function does not change anything.
     
    Last edited: Aug 3, 2018
  6. NSANGOU CHOUAIBOU

    NSANGOU CHOUAIBOU Active Member

    Hi Yunze,
    That is how Novelda X4M200 algorithms works. If you want custom respiration and sleep profiles with different number of bins, you need X4M03 development kit to be able to develop your own sensor from scratch.
    Note : You are able to modify detection zone, but you will still have different number of bins according to the selected profile (respiration or sleep).

    B.R
     
  7. Yunze

    Yunze New Member

    Hi B.R,

    Thanks for the explanation. Then, what does modifying detection zone really change?
     
  8. NSANGOU CHOUAIBOU

    NSANGOU CHOUAIBOU Active Member

    Hi Yunze,
    Modifying detection zone will change the detection zone (boundaries) settings of your radar module accordingly.

    Best regards.
     
    Charlie Shao likes this.