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SYH24A1 24G Millimeter Wave Radar
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SYH24A1 24G Millimeter Wave Radar
Instruction Manual
1. Principle
Millimeter-wave radar is a sensor that transmits and receives electromagnetic
waves through a radar antenna and measures the amplitude and position of an
object's movement. After analysis by the algorithm, the human body's
breathing, movement, number of people, distance, direction and other
information are judged.
2. Application
The millimeter-wave radar is not affected by temperature, humidity, noise,
airflow, dust, and light, and is suitable for use in harsh environments; suitable
for the care of the elderly, management of hotels and guesthouses,
management of office personnel, intrusion alarms, barrier prevention Hit
reminders, population statistics, etc.
3. Detection range
The area that the radar module measures human activity is within about 200
square meters, the maximum sensing distance for object movement is less
than 20 meters, the measurement breathing distance is within 5 meters, and
the radar antenna has a measurement range of 80 ° horizontally and 30 °
vertically. It is a product that can measure different distances through different
algorithms.

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Figure 3-1 Demo picture of module measurement range
4. Installation method
By monitoring different detection distances and different motion amplitudes,
appropriate deployment is made according to the room layout. When indoors,
it will have a better experience when installed at a high place.
Horizontal installation
When installed horizontally, standing or sitting posture is more conducive to
monitoring. Suitable for office, home appliances, barriers, living room and other
open environments.
1-1.5m
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Figure 4-1 Horizontal installation method detection diagram
The horizontal installation height of the radar module is recommended to be 1
m to 1.5 m. The radar is installed horizontally and positively, and the installation
inclination angle is within plus or minus 5 °. There should be no obvious

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obstructions and coverings directly in front of the radar module, and it should
cover the human movement area as far as possible.
In this installation mode, the maximum distance for human motion detection
is greater than 10 meters; the maximum distance for human stationary
detection is approximately equal to 5 meters; generally the effective action
distance is 3 to 4 meters.
Inclined installation
Measure the movement of people in the room. It is mainly suitable for hotels,
halls, courtyards and other environments.
2m-3m
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10°-30°
Figure 4-2 Detecting diagram of oblique installation
It is recommended that the height be 2-3 meters when installed obliquely; the
range of the tilt angle of the radar module when viewed from the bottom is
10 ° ～30 °, and there should be no obvious obstructions and covers in the
direction of the module.
In this installation mode, the maximum distance for human motion detection
is less than 10 meters; the maximum distance for human stationary detection
is less than 5 meters, and the effective distance is generally 3 to 4 meters.
In this mode, there may be monitoring blind spots directly below the radar and
adjacent areas. As the downward looking angle increases, the static human
detection distance will be significantly shortened.

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Topinstallation
Mainly for the monitoring of the human body in the state of lying down, such
as bedrooms, nursing homes, hospital beds, etc., can measure a person's
breathing state, sleep state.
2m-3m
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Figure 4-2 Top installation detection
The radar is installed vertically to ensure that the radar scan covers the
detection area; the radar installation height is recommended to be 2-3 meters;
there is no obvious obstruction and cover in front of the radar. Affected by the
radar installation height and the radar beam range, the length of the
horizontally acting area is about 3 to 5 meters.
5. Output content
The radar module can periodically give the presence and movement status of
people in the monitoring range.
The main states that can be given include:
(1) No one's situation;
(2) Someone's condition-static state (sleep state);
(3) Someone's condition-active state;
(4) Someone's condition-approaching state;
(5)Someone's situation-stay away.
6. Matters needing attention and common problems
(1) Startup time

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When the module starts to work when it is initially powered on, it is necessary
to completely reset the internal circuit of the module and fully evaluate the
environmental noise to ensure the normal operation of the module. The module
initialization time is about 30 seconds, and the validity and accuracy of
subsequent output parameters can be guaranteed after the initialization is
completed.
In extreme cases, some users have high electromagnetic noise in the use
environment, which can easily cause misjudgment of the status. In the case of
the current harsh environment, the internal algorithm of the module supports
the learning and adaptation of the existing environment characteristics in an
unmanned scenario to reduce the misjudgment caused by the module detection
in a harsh environment. The learning process needs to be powered on in an
unmanned environment. Run for about 2 hours.
(2) Judgment time
Within the radar detection range, the detection and feedback time when the
object is moving is within 1 second, and the data is output synchronously.
Because of the algorithm's superimposed calibration, the radar needs to collect
data in multiple dimensions and improve the accuracy when detecting the
stationary human body or the unmanned state evaluation to ensure the
reliability of the radar output state. The radar output evaluation time is
currently set to 10 minutes, and the response time can be further optimized
according to user scenarios in the later stage.
(3) Environmental factors
For the measurement of moving objects or moving human bodies, it is
necessary to prevent interference from other continuously moving objects in
the environment. This radar has already processed and filtered the data for
long-distance moving objects in algorithm, but if there are other moving objects
in the short-range monitoring range, interference data may be uploaded to the
module to cause incorrect data judgment. In actual use, in order to ensure the
accuracy and stability of the output data of the radar module, objects that may
cause interference should be avoided from entering the detection range, such
as household fans, automatic toys, and fish tanks with fish activities.
(4) Effective detection distance
Radar effective detection distance is related to the motion amplitude and
distance. The larger the object's motion amplitude, the farther the detection
distance is. The detection distance of human motion data is within 20, and the
detection distance of human respiratory data is within 5 meters.
(5) Penetrability

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The antenna of this radar module has a fixed angle output. The millimeter wave
can penetrate clothing, bedding, glass, wooden boards and other materials, but
cannot penetrate the human body and walls.
(6) False positive rate
Human biological signals belong to ultra-low frequency, weak reflection
characteristic signals. The radar module needs a relatively long time to perform
data accumulation and data processing. In the process of data accumulation,
many factors may affect the radar parameters. Occasional detection failures
are normal. You can reduce the false alarm rate by adjusting the installation
angle and distance.
(7) Radiation
The output power of this radar module is very low, the signal power is less than
one tenth of that of a mobile phone, and there is no risk of excessive radiation
or radiation pollution.
(8) Power supply
The operating power consumption of this radar module is about 0.5W. It is
recommended to be used with a power adapter. It is not suitable for
applications powered by separate batteries.