Powerwave Technologies Inc. 5JS0059 Manuale Utente
044-xxxxx Rev. x
4-2
4-4.3. DRIVER AMPLIFIER
The driver amplifier consists of two stages of class AB amplification which provide approximately
40 dB of gain in the 60 MHz frequency band from 1930 MHz to 1990 MHz. The amplifier operates
on +26 Vdc, and a safe bias voltage which is controlled by microprocessors.
The driver amplifier consists of two stages of class AB amplification which provide approximately
40 dB of gain in the 60 MHz frequency band from 1930 MHz to 1990 MHz. The amplifier operates
on +26 Vdc, and a safe bias voltage which is controlled by microprocessors.
4-4.4. MAIN AMPLIFIER
The main amplifier employs two class AB amplification stages for maximum efficiency. It provides
approximately 25 dB of gain in the 60 MHz frequency band. The output from the main amplifier is
typically 48.6 dBm. The amplifier operates on +26 Vdc, and gate bias voltages controlled by
microprocessors.
The main amplifier employs two class AB amplification stages for maximum efficiency. It provides
approximately 25 dB of gain in the 60 MHz frequency band. The output from the main amplifier is
typically 48.6 dBm. The amplifier operates on +26 Vdc, and gate bias voltages controlled by
microprocessors.
4-4.5. MULTIFUNCTION BOARD
The multifunction board consists of control and alarm circuits. The MCPA communicates to the
host system through the multifunction board which gathers the status information of the amplifier
and reports to the host system via the RS485 interface when instructed. It also protects the MCPA
from adverse conditions such as overpower, input overdrive, overvoltage, etc. A microprocessor
on the multifunction board also controls two loops in the feed-forward system.
The multifunction board consists of control and alarm circuits. The MCPA communicates to the
host system through the multifunction board which gathers the status information of the amplifier
and reports to the host system via the RS485 interface when instructed. It also protects the MCPA
from adverse conditions such as overpower, input overdrive, overvoltage, etc. A microprocessor
on the multifunction board also controls two loops in the feed-forward system.
4-5. AMPLIFIER MODULE COOLING
Each amplifier module is contained within a thermally conductive chassis which, when properly
mounted on an adequate thermal surface, will provide sufficient cooling to maintain the amplifier
within the specified operating temperature range.
Each amplifier module is contained within a thermally conductive chassis which, when properly
mounted on an adequate thermal surface, will provide sufficient cooling to maintain the amplifier
within the specified operating temperature range.
4-6. POWER DISTRIBUTION
Primary DC power for the amplifier is provided by the host system. The amplifier generates all the
required voltages internally from the main source.
Primary DC power for the amplifier is provided by the host system. The amplifier generates all the
required voltages internally from the main source.
Figure 4-1. NTGY81AC Multichannel Power Amplifier Functional Block Diagram
RF
IN
INPUT
AMPLIFIER
PREDISTORTION
AMPLIFIER
DRIVER
AMPLIFIER
MAIN
AMPLIFIER
RF
OUT
MULTIFUNCTION BOARD
(ALARMS AND LOOP CONTROLS)