CommScope ATC300-2000 - Manual (Page 180)

Bulletin 639544 • Revision L August 2014 23-1
Section 23
Tower Mounted Amplifier
23.0 Section Overview
Andrew tower mounted amplifiers (TMAs) are installed near the Tx/Rx antenna at the top of a cell
tower. A base station antenna transmits a much stronger signal than what it receives back from the
mobile phone, but the TMA corrects this imbalance. This uplink improvement with a stronger, clearer
signal results in fewer dropped calls, improved call quality, and better coverage.
The Andrew tower mounted amplifier extracts the AISG signal and dc power from the coaxial cable
run and delivers it to the antenna RET line devices through its AISG interface.
23.1 AISG TMA (Tower Mounted Amplifier) Applications
• An AISG TMA usually includes its own bias tee at the top of the system to get the dc voltage. If
a TMA already uses a bias tee, a top Smart Bias Tee unit is not needed, nor can it be used.
(The top Smart Bias Tee unit cannot pass dc power and data to the output RF port.)
• A bottom Smart Bias Tee unit can be used to pass dc voltage and data to the coax line in
applications where an AISG TMA has its own bias tee at the top of the system.
• If a system includes both an AISG TMA and actuator(s), the TMA must have an AISG connector
that can pass the dc power and data to the AISG jumper cable assembly.
23.2 Finding TMAs
Click on 1. Find Devices from the controller’s main screen (Figure 23-1).
Click on 2. Start Scan to activate the device search. Figure 23-2 shows a completed device scan.
Click on 3. Home to return to ATC300 controller’s main screen (Figure 23-2).
Any RET devices found are initially listed on the main screen. Click on the 4. Show TMAs button to
see all TMAs found in the device scan. See Figure 23-3.
Figure 23-4 shows that one AISG TMA product is installed at the site. 5.