Seeed MR24HPB1, Руководство пользователя

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MR24HPB1
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7.2. Effective Detection Distance
For the time being, this radar module does not feature a ranging function. Its range of
detection is closely related to the RCS of the target and the environment in which it
operates. Therefore, the effective detection range may change depending on the
environment and the target. So, it is normal for the effective range of detection to change
within a certain range.
7.3. Radar Bio-detection Performance
Since human biological characteristics are characterized by ultra-low frequencies and
weak reflections, the accumulation process of the radar will be relatively lengthy.In the
process of accumulation, many factors can influence the radar parameters. It is therefore
normal for accidental detection failure to occur.
7.4. Power
This radar module has a higher power quality requirement than conventional low-
frequency circuits. The power supply must be free of threshold burr and ripple and
protect the module from power noise from accessories.
The radar module should be well-grounded. As a result of ground noise caused by other
circuits, the radar module may perform poorly or even malfunction. In most cases, the
detection distance becomes closer, or the false alarm rate increases.
The module's power supply must be with +5v ~ +6v and a voltage ripple of 100mV to
ensure the normal operation of the module's VCO circuit.
External power supplies must provide sufficient current output and transient response
capability.
8. FAQ
Interference factors
The radar is an electromagnetic wave sensor, and the presence of an active nonliving
object will result in a false alarm. Metal and liquid will cause the radar to make an
incorrect judgment. An electric fan, a pet within range of the radar, or the sway of the
curtain can all cause miscalculations. Therefore, the installation angle of the radar
should be considered.