Isuzu D-MAX 2020, Owner'S And Driver'S Manual

Page: 910 / 924

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MAIN DATA
4. Care shall be taken when sitting an antenna next to an existing one or when
mounting antennas with magnetic bases, as this could affect the accuracy or
operation of the compass on vehicles so equipped.
[Radiation patterns and ground planes]
1. In order to create a symmetrical, non-directional radiation pattern, an antenna
needs to be mounted vertically on a horizontal ground plane with – ideally – a
radius of > λ/4 at the lowest frequency band used (see Table 1).
2. The antenna should not be located close to any electrically resonant structure.
3. Care shall be taken when sitting the antenna close to another, existing antenna. It
is necessary to separate them by > λ/4 for transmit frequency f < 600 MHz and >
λ for transmit frequency f > 600 MHz (see Table 1).
Table 1. Approximate frequency-to-wavelength conversion
Frequency
f
MHz
Wavelength
λ
cm
λ/4
cm
50 600 150
80 375 94
150 200 50
450 66 17
600 49.5 12
900 33 8
1800 16.5 4
[Ground-plane provision]
When the antenna installation is to be carried out on a non-metallic surface
• a ground-plane-independent antenna can be fitted directly to any surface (glass-
fiber etc.) or onto a mounting bracket which may be supplied by the manufacturer,
• a standard antenna can be used with a ground plane fitted to the underside of the
panel, for example a metallic plate complying with dimensions Table 1.
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