Chapter 4 Measurements
Antenna to Antenna Isolation
Introduction
Measuring antenna-to-antenna isolation between adjacent systems is very important when deploying multiple systems on the same tower. It helps to determine the potential threat of interfering signals and maximizes the capacity of the base station.
An example of adjacent PCS systems is shown in Figure 4-15.Antenna 1 transmits a signal in a specific direction, but some of the signal is received by Antenna 2. Any excessive sig- nal level from System 1 can cause poor performance, loss of communication, and system degradation in the adjacent System 2.
Figure 4-15. System Isolation
Antenna-to-Antenna isolation, more commonly known, as system isolation, is the differ- ence between the output level transmitted by System 1 and the signal level received by Sys- tem 2.
System isolation is equivalent to the reduction in the signal level (attenuation) of Transmit- ter 1. Typical levels for isolation between systems can vary from 50 dB to 100 dB.
