Comtech EF Data LPOD-R PS .5, Инструкция по установке и эксплуатации

Страница: 24 / 152

LPOD-R Outdoor Amplifier / Block Up Converter (BUC) MN-LPODR
Introduction Revision 3
1–4
Figure 1-2. LPOD-R Typical Block Diagram
1.4.2 SSPA Module
The amplifier module performs the core function of the unit. An isolator is at the
RF input to ensure good voltage standing wave ratio (VSWR). The RF signal then
passes through an electronically controlled attenuator that adjusts the overall
attenuation according to the user input. After some amplification, a second
attenuator is automatically controlled via a look-up table to maintain the
amplifier gain at a constant level over temperature variations.
The RF signal is then amplified by a multi-stage design that utilizes proprietary
combining techniques to meet the rated power requirements. The output
circuitry contains a coupler to provide a sampled signal for monitoring purposes.
A power detector circuit also is included and the reading can be accessed via
remote communication. A high power circulator and load is located at the output
to provide good VSWR and protection from external mismatch.