When we say Radiative testing, it usually refers to various different types of configurations as shown below. These are just a few typical examples that you may see most often, but these are not all. There are so many different variations of Radiative Test Setups. Even though the terms OTA Test and Radiative Test can be used interchangeably, when we say OTA test without any specific details, we normaly think of the configuration like (C) or (D) shown below. As shown below, it is test in a chamber lined with absorbers (this kind of chamber is called Anechoic chamber. Anechoic means 'No Echo'. 'No Echo' in this case mean 'No reflection from any object in the box).
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| (A) | (B) |
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| This may be one of the simplest way. We use a wide planar patch antenna and put the DUT on top of the antenna pad. Very convinient for the test like protocol or function test which does not require accurate RF measurement. However, unless you does not use this setup within a shield room, it may suffer from the interference from surroundings (e.g, from live network or other equipment) | In terms of Antenna setup, this is almost same as (A). But in this case the antenna pad and UE is within a small RF chamber. The benefit of this type comparing to (A) is that it can block the interference signal(e.g, interference from live network or neighbouring equipment) |
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| (C) | (D) |
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| This is a chamber made up of a conductive metal (usually copper). As in (B), this can block the interference from surroundings and at the same time it can reduce the interference from reflections in side of the box. When a electromagnetic wave from DUT or equipment hits the conductive wall, large portions of the wave can be obsorved by the conductor. | This would be the ideal solution for OTA test which requires a certain level of measurement accuracy. It is lined with special absorvers and usually has positioner in it which can change the direction of the DUT by external conroller. |