DWG2000E/F/G GSM/CDMA VoIP Gateway User Manual
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Shenzhen Dinstar Technologies Co., Ltd.
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6. The Way to Increase Antenna Isolation
Several methods are introduced in this document to decrease the interfering effect
among antennas with close mounting position.
6.1 Isolate by distance
figure-6.1 Theoretic distance value for GSM band
Keep distance between antennas as far as possible. In theory, the distance between
antennas should be more than half of the operating wavelength. For GSM band, the
recommended distance value is more than 20cm.in practical application, the
experiment value is no less than 15cm for better isolation.
6.2 Isolate by metal shielding baffles among antenna
Put a metal shielding baffle between antennas, which can help to prevent radiation
signal coupling from each other. If the metal baffle is big enough, the isolation
will be unlimited big in theory.
Figure 6.2 Isolation by metal shielding baffles