User Manual

Epoch-S02-19002W RF Repeater
User Manual V1.3
Advanced RF Technologies, Inc. Proprietary Document Page 5 of 33
1. Installation Guide for Epoch-S02-19002W
1.1 Environmental Requirements
1.1.1 Antenna Separation/Isolation
Separation between antennas is necessary to prevent oscillation.
Oscillation occurs when the signal entering the system continually
reenters, due to the lack of separation between the donor and server
antennas. In other words, the signal is being fed back into the system.
This creates a constant amplification of the same signal. As a result, the
noise level rises above the signal level.
To prevent feedback, the donor and server antennas must be separated
by an appropriate distance to provide sufficient isolation. Isolation is
attained by separating antennas a sufficient distance so that the output
of one antenna does not reach the input of the other. This distance is
dependent on the gain of the repeater.
A sufficient isolation value is 13 ~ 15 dB greater than the maximum gain
of the repeater. For example, if the gain of the repeater is 50 dB, then an
isolation of 63 ~ 65 dB or greater is required. In the same manner,
because the Epoch-S02-1900 has a maximum gain of 90 dB, it requires
an isolation of at least 103 ~ 105 dB.
Do nor Se rve r
RF Re p e a te r
Figure 1 - RF Repeater Oscillation