User's Manual

P RODUCT M ANUAL C OMPACT R EPEATER D EKO 3178B D EKOLINK W IRELESS L TD .
Page 16 Proprietary Data Pub. 300TC80031 Rev. 1.55
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4 ANTENNAS INSTALLATIO
ANTENNAS INSTALLATIOANTENNAS INSTALLATIO
ANTENNAS INSTALLATION AND
N AND N AND
N AND
CONNECTION
CONNECTIONCONNECTION
CONNECTION
4.1 RF G AIN S ETTING C RITERIA
In order for the CBDA Dual Band BDA to operate effectively the isolation between the
base station and the mobile antenna must be at least 15 db higher than the CBDA gain .
The step attenuator on the low noise amplifier can reduce the CBDA gain. The CBDA
gain can be reduced by the amount indicated on the step attenuator.
Note: A higher CBDA gain than the isolation between the antennas would cause
oscillation which would saturate the amplifier. On the other hand, if the isolation were
only a few db higher than the CBDA gain, it would not be enough to cause oscillation
however it would cause gain ripple in the band.
4.2 A NTENNA I NSTALLATION
4.2.1 Base (Donor) Antenna
NOTE: Verify that the antennas meet requirements described in section 2.2.1.
Installation requirements:
• The antenna should point to the direction of the base station for maximum input
power
• Verify that the antenna is in the base stations line of sight (raise the antenna if
necessary)
• Install the donor antenna at a higher level (i.e. floor) than the mobile antenna
• Must be installed at a minimum distance of 1 meter from any personnel within the
area.
4.2.2 Mobile (Service) Antenna
NOTE: Verify that the antennas meet requirements described in section 2.2.2.
Installation requirements:
• Install the service antenna on the ceiling or on the wall so it would shadow the
required coverage area within the in building environment.
• Installation of this antenna must provide a minimum separation distance of 0.5 m
from any personnel within the area.
• Cable and jumper loss is at least 2dB.