Operator's Manual

CI Wireless Inc. Installation of the CDR812
MirrorCell Select CDR812 Manual
Rev. X1 7-3
7.4.2 Server Antenna Mounting and Isolation Measurements
Isolation measurements should be taken to ensure proper operation of the repeater.
Measurement of isolation can be accomplished easily by following the procedures, as
illustrated in Figure 15.
1. Mount server and donor antennas at initially chosen location to obtain
desired coverage.
2. Inject a known signal within the bandwidth of operation into the donor
antenna. An unused channel within the band should be used. The signal
should be at least 1W in order to allow for an accurate measurement of
isolation. The repeater and a low-power signal generator can be used in
series to generate a signal of sufficient strength. The repeater will add 65dB
– 95dB of gain, depending upon how much attenuation is added to the
repeater.
3. Connect a signal measurement device, such as a spectrum analyzer, to the
server antenna. Measure the received signal level. The difference between
the signal input to the donor antenna and the received signal measured
after the server antenna is the antenna isolation. (Note that the gain of the
antenna is not used in the calculation.)
Figure 4. Isolation Measurement Setup.
SPECTRUM
ANALYZER
RF In
SIGNAL
GENERATOR
RF Out