Yesterday, I wrote an article to explain why low-frequency bands used in terrestrial networks are always configured in FDD (Frequency Division Duplex) mode. In this article, I would like to discuss why all kinds of Satellite Bands (including high-frequency) are always configured in FDD mode. In order to understand this fact, we need to analyze what happens in case Satellites exchange RF signals with ground-based terminals in TDD (Time Division Duplex) mode.
Satellites in TDD Frame
Let’s assume a TDD frame for a satellite looks something like this.