RF Power Amplifiers
Andrew Corporation – Power Amplifier Group
Propriety – Use pursuant to Company Instruction
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3.
Functional Blocks:
The Andrew RF100739 (RM2 850) includes 3 lines of RF amplification.
Each of them contains the following functional areas:
−
Power Amplification Line-Up
This block gives to the unit its specified gain through 4 amplifier stages: 1 pre-
amplification stage, 1 medium power stage, and a final 2-stages power transistor. This
power final stage brings the signal to its desired high power level. It is the heart of the
RF section of each TX path. The unit power, linearity and efficiency essentially come
from this block.
−
Power Conversion and Conditioning Circuit
This block is made of a DC/DC converter and various voltage adapters to do the
interface between the customer supply network and the internal functions of the unit. It
provides all the voltages and signal interface to the internal blocks of the unit.
−
Monitoring and Control Circuit
Several internal features enable to monitor and control the internal parameters. The
signals provided by these circuits could have different nature (current image, voltage
image, RF power image, temperature image). All these signals, transmitted through
analogical lines, are exchanged with the customer controller circuit through an interface
connector (common for the 3 TX paths). It is critical that signals are not interfering prior
sent to the customer controller circuit. It means that one transmitting TX must not
interfere with other TX analogical lines.
