User's Guide

12/6/2019
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Advanced Information. Antennas and QUATRA 4000
Donor Antennas
Donor Signals
A good donor signal, arriving as cleanly as possible, to the NU, is perhaps the most important consideration in
driving the best experiences and outcomes with QUATRA 4000.
With regard to 4G LTE, there are two metrics of particular importance to monitor and optimize:
1. RSRP. Reference Signal Receive Power. It is the power of the LTE Reference Signals spread over the full
bandwidth and narrowband. A minimum of -20 dB SINR (of the S-Synch channel) is needed to detect
RSRP/RSRQ
In the context of Cel-Fi QUATRA 4000, the following stratification of quality is recognized:
2. SINR. Signal to Noise Ratio. The SINR is the ratio of the usable (desired) signal over the noise. The
following metrics should be used when assessing SINR in the context of Cel-FI QUATRA 4000.
Antenna Selection
There are a few considerations to make when determining the donor antenna.
1. How many serving sites? If there are multiple serving sites, and the design goal is to select a specific site,
for loading, or any other reason, then a directional antenna would be required. If there is a single donor site,
and not much RF contention, than an omni-directional antenna could be considered, which would save a
little time and energy in the install process, as it would not need to be aimed.
2. How much noise? If the site location is very noisy, then a strong directional antenna would be a good
choice, as it will filter out some of the unwanted signal.