Difficulty tracking respiration using X4M200

Discussion in 'Respiration Sensor' started by JasonLevine, Feb 27, 2019.

  1. JasonLevine

    JasonLevine New Member

    Hello XeThru Community,

    I recently purchased an X4M200 sensor with the goal of tracking respiration. After 3 days of extensive testing, I have been unable to track respiration.

    I tested the sensor in multiple positions with various settings:
    1. I reproduced the exact setup and settings used in this video and had no success -> . Curiously, when sitting right next to the sensor at 90 degrees it picked up my movement clearly, while lying down still with my sternum in the line of sight of it picked up no movement. Is the radar reflecting off of walls?
    2. I reproduced the setup in this image: https://www.xethru.com/community/resources/x4m200-sleep-recording-introduction. I placed the sensor on my night table 1.5 metres from my sternum and experimented with various settings. I was only able to get the sensor to recognize breathing once or twice by exaggerating my breathing to the extreme.

    3. I attached the sensor above my bed, 1.2 metres above my head, rotated 30 degrees such that my sternum was in direct line of sight. This position had the most success but only picked up respiration when extreme deep breathing.

    4. I placed the sensor 2 metres away at a 90 degrees from the user pointing a couple centimetres above the users ribcage. Despite testing various settings, I had no success with this sensor position.
    Any suggestions for how to succeed at tracking respiration? I have tried both respiration settings (feature optimized and memory optimized), the suggested positioning as well as other positions, various sensitivity, noise map, and distance settings.

    Please advise.

  2. Charlie Shao

    Charlie Shao Moderator Staff Member

    Hi Jason,
    I am not sure why this happens, but just give you some hints on why this could happen:
    1. When you sitting down or laying down, making sure your other parts of the body have no movement except normal respiration. This how we define still.
    2. Keep still for at least 20s, the sensor has a time window of 20 to extract respiration signal and verify if it is real RPM, after this, it will start to output RPM value.
    3. Set proper detection zone to include the whole body inside the detection zone.
    4. Make sure there is no other big moving object like fan bringing interference.