Specifications

50 209351 REV B Operations Manual, Redundant System Controllers
4.4 Operation of 1:2 Fixed Phase Combined System with FPRC-1200
The 1:2 Fixed Phase Combined Redundant System is a popular system architecture
that enables Solid State Power Amplifiers to achieve higher output power levels while
building in a level of redundancy. The basic system topology is similar to a 1:2
redundant system and is shown in Figure 4-10. Amplifiers #1 and #3 are normally
online. The outputs of #1 and #3 are directed by the waveguide switches into a fixed
phase combiner such as a waveguide “magic tee” style combiner. In the event of a
failure of either on line amplifier, the standby amplifier, #2, can be switched in place of
either #1 or #3 and the system maintains full output power.
System designers find that the 1:2 Fixed Phase Combined Amplifier System topology
is a very cost effective solution to realizing higher power amplifier systems. For exam-
ple, it is less expensive to configure a 1 kW C-Band redundant system using (3) 500W
Compact Outdoor Amplifiers in a 1:2 Fixed Phase Combined redundant system than it
is to use (2) 1 kW amplifiers in a traditional 1:1 Redundant System.
The FPRC-1200 controller is specifically designed to handle such an amplifier system.
It not only handles all traditional fault monitoring and switching duties but also
provides an overall system monitor and control facility. The FPRC-1200 can adjust the
system gain over a 20 dB range without the need to adjust each of the three amplifiers
individually. It also provides a convenient display of the overall system output power.
Individual amplifier monitor and control can also be achieved through the FPRC-1200
either locally via the front panel or by remote serial communication.
RF Input
Amp 1
Amp 2
Standby
Amp 3
RF Output
Figure 4-10: Block Diagram, 1:2 Fixed Phase Combined System