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Figure 3. iPasolink 400 IDU, block diagram.
Figure 4. IHG ODU, block diagram.
The Outdoor Unit (ODU) generates the final microwave signal using the IF signal from the IDU by
upconverting it one or two times (MIX). The output of the mixer is band-pass filtered (BPF) in order to
remove the unwanted mixing products and then power amplified (PA). In the receive direction there is a
Low Noise Amplifier (LNA) and a mixer/filter which generates the receive direction IF signal. The local
oscillator (LO) frequencies are synthesized and controlled by the Control unit (CTRL). Transmitter output
power is fine-controlled automatically according to the modulation used and optionally based on the
remote end received power (Automatic Transmit Power Control, ATPC).
Both the modem in the IDU and the ODU contain a duplexer (DUP, MPX) which combines the different
directions of transmission to the same cable connector. The ODU power supply uses the DC voltage (-48V)