For NR SA EPSFB before redirection to LTE, does UE measure target LTE cell?

Hello Experts.

For NR SA EPSFB before redirection to LTE, does UE measure target LTE cell or not?

Can we do 5G SA to LTE redirection in poor coverage for data call or not?

Dear Experts.

In 5G SA UE is handed over to legacy networks (4G) by EPS fall back procedure.

What will be UE behaviour once Voice call is over and UE goes to idle mode?

Will it be redirected to 5G or it will be handover from 4G to 5G?

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After call end ideally it need to reselect back to 5g SA .

Need to check network end features like in 3G to 4G case we have smart LTE layering etc. features.

Yes ideally it needs go back to 5G SA but it will be redirection or handover?

There are below ways to push UE back to SA ,NW might use any of those depending on deployement.
1.NW sends LTE RRC Release with redirection and includes SA ferquencies -This is fastest way
2.NW sends LTE RRC release and sets dedicated SA cell priorities Higher compared to Current LTE Cell
3.NW releases LTE RRC connection( after any ongoing data session is completed) and UE reads SIB 24 which has SA frequencies

As of now LTE to 5G PS Handover is not yet supported so above are the only ways

Here are my observations for live NW traces
For NR SA EPSFB before redirection to LTE, does UE measure target LTE cell or not?
–>No its blind redirection-UE decodes SIBs and selects LTE cell which is already provided in Redirection msg.
Can we do 5G SA to LTE redirection in poor coverage for data call or not?
–>Yes…this is possible but for poor SA coverage scenarioes mostly it should be measuement based redirection to LTE…