User's Manual

Chapter 2 System Description
2.3.15.1 Transmission Sub-system Controller (TSC)
The Tra
nsmission Subsystem Controller (TSC) serves as an agent for the exciter to
communicate with and manage the HPA sub-system. The TSC accepts commands from the
exciter to enable or disable the RF output and set the output power target.
The HPA sub-system is a variable gain HPA assembly, which is controlled via the TSC’s ALC
algorithm. The ALC algorithm monitors the forward power level at each of the HPA/TSC
transmit output couplers and equally adjusts the output power level of the individual 400W
HPA’s to reach the targeted value.
The TSC monitors and controls the HPA’s (and their slave power supplies) over a RS-485
serial bus and reports the HPA’s statuses and alarms back to the exciter via a RS-422 serial
interface.
The TSC is also connected to temperature sensors, which are mounted on the 4-way hybrid
combiner and magic tee termination loads. This allows the TSC to monitor the temperature
of the termination loads and prevent them from overheating.
Figure 2-27 TSC
SX03-30000-01-M01
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