Codan Radio Communications CASC165A Manual De Usuario

Cascade Power Amplifier

Cascade System Modules Operation Guide

OG-CASC-SYS-MOD-1-0-0P

INSTALLATION

One or two power amplifiers can be inserted into the CASCADE subrack. The power amplifier is 

fastened with two Phillips screws at the front of the subrack (see Figure 13).

FIGURE 13: Power Amplifier Subrack Locations

CONNECTIONS

The PA requires DC power from the 48V PSU which is supplied to the front of the PA. The ribbon 

cable connector on the bottom front is used to communicate with the other components of the 

CASCADE system. The input and sampled output signals are connected to the transceiver units via 

short cables with SMA connectors. The output is delivered via a Type-N female connector at the back. 

THEORY OF OPERATION

The PA is designed to amplify an input signal with modulation characteristics that produce a spectrum 

with a 5dB peak to average ratio with high fidelity when operated in a Cartesian loop. A further 

requirement is that the output should be variable in 1W steps from 40dBm (10W) to 51dBm (125W) 

nominal. This is accomplished by internal variable attenuators in the amplification path as well as in 

the sampled output path setting up the appropriate power window for the Cartesian loop controlled 

from the transceiver module. 

The output voltage standing wave ratio (VSWR) is monitored, as well as the heatsink temperature. 

Protective action is taken under severe thermal and VSWR, as well as fault conditions by the control 

system.