Satellite Dishes -- Main Types

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Satellite Dishes -- Main TypesWhen you choose which satellite dish to buy, the first thing you need to do is to choose the design. The most common satellite dish is a parabolic-dish asymmetric offset focus antenna or, to put it in simple words, an offset satellite dish.One more popular type is an axial-symmetric parabolic-dish antenna or axial-symmetric satellite dish. They differ by their design and signal passage. In terms of operation, these two satellite dish types have different directions of a reflected signal - that is, by the reflector direction.In offset satellite dishes, a satellite signal gets to the internal part of the dish spherical reflector at a certain angle. After being reflected, the signal is focused on the converter feed located at the bottom. So, offset satellite dishes have the focus shifted downward to the lower part of the satellite dish. Therefore, they are called asymmetric.In axial-symmetric satellite dishes, a satellite signal is focused in the centre of the spherical reflector. That's why such antennae are called symmetric.Thus, antennae design is a key difference between offset and axial-symmetric satellite dishes. But this is only a technical aspect. The most considerable difference lies in their position.Axial-symmetric satellite dishes looks directly at the satellite while offset satellite dishes have a certain slope. It seems to be directed downwards as if it received signals reflected from the Earth. However, the satellite dish reflector will be gradually lifted as far as it is located closer to the equator.Before buying a satellite dish, you will have to choose the antenna design that fits best to your situation and demands. To this end, you need to consider in detail advantages and disadvantages of offset and axial-symmetric satellite dishes.