Multiple TDD patterns in 5G

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Hello all.

Regarding 5G NR, does anyone have experience with multiple TDD patterns?

Like in this example of N78:

TDD-UL-DL-Pattern field descriptions

dl-UL-TransmissionPeriodicty
Periodicity of the DL-UL patter, see TS 38.213 [13], clause 11.1. If dl-UL-TransmissionPeriodicty-v1530 is signalled, UE shall ignore the dl-UL-TransmissionPeriodicty

Thanks.

I found it in 38.331.

My question is do you see often 2 patterns used?

Yes, usage of 2 patterns can be seen for e.g.: when UL/DL slot ratio is used as 3/7.

E.g. of slot ratio 3/7

Wouldn’t it be easier to use just one pattern with similar parameters?

Why so complicated?

I mean one pattern provide enough flexibility with UL / DL slots and UL / DL symbols.

Everything can be achieved with one pattern, why do we need 2?

Because 2 patterns introduce more separation symbols, so some slight resources are lost this way.

I agree that one pattern may introduce delay, because UE needs to wait longer time for an uplink slot.

May be few patterns are standardised, as only pattern 1 will be used for case of 1/4 slot ratio.

It is not like in LTE, where are standard 6 or 7 patterns for TDD.

In NR is much more flexible a pattern.