TDD Duct Phenomena Interference



Atmospheric ducting mode -- the waves are bent by the atmospheric refraction as shown below:






Using this model, the downlink signal of the interferer eNB can travel for hundreds of Km which will result in an additional time offset when arriving at the interfered area, this delayed DL signal will impact the uplink signal of the TDD subframe (it will be considered as interference compared to our useful UL signal).

In the case of coastal areas, the impact of phenomena will increase with the increase of the temperature (Evaporation of seawater increase => hydrometer scatter).

You can expect to experience regularly this kind of degradation during Spring and Summer until the temperature will decrease (starting from Autumn).


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