Why GSMA recommended using DDDSU TDD structure across countries?

Hi Experts.

Why GSMA recommended using DDDSU TDD structure across countries?

If interference is an issue from a neighboring band, then how are we going to use other TDD structures?

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TDD it is important to adopt this second frame structure and synchronisation need to be made between all operators in the country or state and operators of surrounding countries using the same TDD band, otherwise huge interference will be experienced.

Similar frame collision or out of sync of GPS.

Hence TDD must have GPS all sites.

All Operators discuss and agree to same mode.

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After a large guard zone (>60km) or a high natural obstacle you may change TDD frame structure.

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Similar to ducting?

Total daily throughput volume from public network is that ~90% is DL & ~10% UL.

DDDSU is most common MNO slot config.

For interference with neighbor cell, eICIC, freq. selective scheduling, IRC technology used.

For example, apply MMSE-IRC instead of MMSE when high UL interference.

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But then when are we going to make use of the flexibility of TDD structure if the whole world is using DDDSU?

Public vs. private N/W are different use cases.
Mobile subscribers are heavily DL focus.
But enterprise may have opposite use case.
For example, if you are building private network for UAV.
This requires heavy UL (sensor data; image/thermal cameral ) vs. light DL (flight control).
slot config could be DSUUU.