What determines beam switch delay in 5G mmWave networks?

Hi Experts,

We are trying to analyze the root cause of beam switch delay for our analysis of beamforming performance in commercial 5G mmWave network in the U.S
We figured out that, whenever there is a beam switch, the “beam switch delay” recorded by the UE varries and it is the multiples of 160ms
Here is an examples of a Verizon traces using Samsung devices with 48 SSB beams active


Our analysis showed that this delay is calculated as the time different between two " ML1 Searcher Measurement Database Update Ext"

We understand that the phone needs sometimes to be ready to receive from the new best-RSRP beams, but we don’t get why this delay varies too much. Sometimes it can take more than 1 seconds for beam switching. Any insights on what may influence this delay? And why is it a function of 160ms (depending on the operators/devices)?

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Hi, I was looking into it.

The question is interesting.

https://wcsng.ucsd.edu/mmNets2023/assets/files/feng.pdf I would start from it.

It shows the difference in config between Verizon and AT&AT, secondly DRX for sure can have impact and I would ask about beam switch success rate ( pointing deviation) if it degrades then it may have impact on time too + maybe the photo below?

See US Patent for Downlink signal reception with antenna panel switching Patent (Patent # 11,689,273 issued June 27, 2023) - Justia Patents Search (beamSwitchingTiming ) for more details

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