User's Manual

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MSAN
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9
K-Band Miniature Doppler Transceiver Module
Application Note
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ST Electronics (Sa
tcom & Sensor Systems) Pte Ltd
1 Ang Mo Kio Electronics Park Road, #06-02, ST Engineering Hub, Singapore 567710
Tel: [phone] Fax: [phone] Email: [e-mail]
Website: www.agilsense.com ( Regn. No.: 199103901W )
It is recommended that the cover placed in front of the module antenna is of flat panel, so that the
beamwidth of the antenna is not significantly distorted. The thickness of the cover, h
1
and the spacing
between the antenna and the cover, h
2
should be ideally half-wavelength of the microwave signal.
In this case, for AP9 series module whose transmission frequency is ~24GHz, the recommended h
1
and
h
2
are 3-4mm and 6mm.
A half wavelength of a 24 GHz in the air is about 6mm. However, the half wavelength of the signal in
other medium depends on the dielectric constant of the material. In the case of ABS which has a
dielectric constant of between 2.5 to 3.5, the half wavelength of the signal is 3 – 4 mm.
Figure 5: Recommended thickness and clearance for ABS placed in front of AP9 sensor
9. Radiation Safety
Microwave radiation from the module is well below established safety standards for general public
environment, like ANSI C95.1-1991 of USA and NRPB-G11 of United Kingdom.
10. Handling
The module has been fully tested to specifications. Upon opening, tighten or loosen the chassis will
cause performance deterioration.
The module is an electrostatic-sensitive device (ESD). Precautions must be observed for handling and
storage of the modules.
h
1
~ 3
-
4 mm
h
2
~ 6mm
ABS
AP9 unit