User's Manual

Page 8 of 14 50W rev 3 - 11/ 03
Dekolink WIRELESS Ltd.
16 Bazel St. Qiryat-Arieh Petah-Tikva, Israel, 49510
Tel- 972-3-9180-180 Fax-972-3- -
e-mail: [e-mail] web www.decolink.com
BDA INSTALLTION
Install the BDA Repeater in a shielded, ventilated and easy to reach area. Use low loss
cables to connect antennas to the BDA. Install the BDA close to the service area to
improve output power and noise figure.
The BDA Base/Donor connector port is connected to donor antenna, usually a Yagi
antenna, while the BDA Mobile/Remote connector port is connected to a mobile
antenna; outdoor indoor.
BASE / DONOR ANTENNA INSTALLTION
Typically this is a directional antenna such as Yagi or Dish antenna of 10 to 15 dB gain.
This antenna is pointed to the base station to get maximum input power. This antenna
should be in line of sight with the base site. Raise this antenna higher if no line of site is
achieved. The required Base signals should be the dominant signals; at least 6 dB
higher power than other signals.
Choose the antenna site to get the maximum isolation from the remote (mobile serving)
antenna.
REMOTE / MOBILE ANTENNA INSTALLTION
The remote antenna is an Omni antenna or a directional antenna according to the
coverage requirements.
For indoor applications covering a large building, the RF signals are split using power
dividers and distributed to many antennas each covering a floor or a small area.
ANTENNA ISOLATION
For proper operation the isolation between these two antennas must be at least 12 dB
higher than the BDA gain. Lower isolation would lead to high in-band ripple. Oscillations
will build up when the isolation is lower than BDA gain.
The isolation between the antennas is critical for high gain outdoor repeaters.
To measure the isolation; inject a known signal into one antenna and measure the
power at the other antenna. This should be done across the frequency range of both
uplink and downlink bands.