Human respiration and heartbeat radar sensor finished product induction

Respiration and heartbeat radar sensor Finished millimeter-wave radar sensing human respiration and heartbeat detection, millimeter-wave radar is a radar that works in the millimeter waveband. Usually millimeter wave refers to the 30~300gHz frequency domain (wavelength is 1~10mm). The wavelength of millimeter wave is between centimeter wave and light wave, so millimeter wave has the advantages of microwave guidance and photoelectric guidance.

Compared to light waves, millimeter-wave radar utilizes an atmospheric window (certain attenuation frequencies due to resonant absorption by gas molecules) and is less affected by natural light and thermal radiation sources.

Therefore, millimeter-wave radar is of great significance in communications, radar, guidance, remote sensing technology, radio astronomy and spectroscopy. Low-elevation precision tracking radars and imaging radars can take advantage of the narrow beam and low sidelobe performance of mm-wave antennas.

1. When the antenna diameter is the same, the millimeter-wave radar has a narrow beam (usually a milliradian level), which can improve the angular resolution and angular measurement accuracy of the radar, which is beneficial to resist electronic interference, clutter interference and multipath. reflection interference.

2. Due to the high operating frequency, large signal bandwidth (such as the order of gigahertz) and Doppler frequency shift can be obtained, which is conducive to improving the measurement accuracy and resolution of distance and speed, and analyzing target characteristics.

The principle of the finished product breathing and heartbeat radar sensor for measuring human respiration and heartbeat is that human activities such as breathing and heartbeat will cause the chest to fluctuate, resulting in changes in the radial distance between the radar and the measured human body. Human respiration and heartbeat signals can be extracted by measuring changes in radial distance.

The detection of finished products of breathing and heartbeat radar sensors is of great significance to medical monitoring, fire, earthquake and other post-disaster rescue. Home health monitoring. Compared with single-target breathing and heartbeat detection, the difficulty of multi-target breathing and heartbeat detection lies in distinguishing multiple targets.

The signal domain multi-target discrimination method is based on the difference of the multi-target breathing and heartbeat signals. The advantage of this method is that it can distinguish multiple targets in the same distance unit, but the breathing and heartbeat signals of the multiple targets are obviously different, and the multiple targets are in the same distance unit. The operating frequency of millimeter-wave radar is between 30gHz and 300gHz; the bandwidth is wide, up to GHz, and the distance resolution is high. Taking the radar bandwidth of 3GHz as an example, the range resolution is 5cm. The high range resolution makes range maintenance for distinguishing multiple targets a viable solution.

Taking the home environment as an example, the two difficulties of multi-person breathing monitoring are:

1) When two/multiple human targets are in the same line with the radar, the radar can only measure the chest fluctuation information of the nearest human target;

2) Background miscellaneous three-wave interference. In a home environment, there are many larger objects that mask the echo signal from the human chest.

This can be applied to the finished product of Fei Rui Technology's 24G breathing and heartbeat radar sensor. Integrated high-performance 32MCU, single-chip direct output of induction control signal, real SOC. It has strong performance, rich algorithms and strong scalability, and is suitable for scenarios with high performance requirements.

It supports standard UART interface, and can be connected with other master controllers or sensors, and can also be used as a master controller to realize presence sensing based on human breath detection.

According to the characteristics of millimeter-wave radar, the finished product of breathing and heartbeat radar sensor can easily meet the following application requirements:

1. High-precision multi-dimensional search and measurement: measure high-precision distance, azimuth, frequency and spatial position;

2. The radar installation platform has strict requirements on the environment such as volume, weight and vibration: the millimeter-wave radar antenna is small in size and light in weight, which is easy to meet the special environmental requirements of different platforms;

3. Target feature extraction and classification and identification: millimeter wave radar high resolution. Wide operating frequency band. Large numerical Doppler frequency response. Short wavelength is easy to obtain target detail features and clear contour imaging, which is suitable for important tactical requirements of target classification and identification;

4. Small target and short-range detection: The optical area corresponding to the short wavelength of mm wave is small, which is more suitable for small target detection than microwave radar.