Release with Redirection to LTE Based on Coverage Check

RAN
1

A question for Ericsson Experts:

We just enabled this Feature on 3G:

Release with Redirection to LTE Based on Coverage Check - RWR(FAJ 121 3960)
Vendor Ericsson

Redirections to 4G Increased.
While logically speaking it should be opposite.

What is the logic here?

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This feature will work in both way:

  1. While losing the LTE coverage.
  2. While having the LTE coverage.

Purpose of this feature is to redirect LTE capable mobile back to LTE Cell only.

So in your case may be network is having good number of LTE sites hence redirection count increased at eUTRAN.

If you don’t want, then you need tune thresholds of these feature in that way.

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I didn’t get it what you mean to say by losing the LTE Coverage and having the LTE Coverage?
The UE is in WCDMA and is measuring the WCMDA Thresholds not LTE here.
The question is even without activating this feature, redirections were happening and they were blind with the triggers defined by RWR basic feature.
Why they increased with this feature? It first checks the 3G levels and assumes 4G coverage will be fine to land based on the thresholds now.

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If I remember correctly:
Previously there was a problem when getting directed from 4G to 3G due to poor coverage.
The UE is stuck in 3G as long as there is a PS session ongoing in 3G.
There was only idle mode redirection or fast return in case of CSSFB but there was no connected mode redirection from 3G to 4G.

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But redirect based CSFB is widely adopted with ps session getting terminated on the network during CSFB call.
Or blind based.
PS connected has lot of drawbacks from carrier definition to NBR well defined, coverage and threshold.

6

Yes, this is surely the case the UE is not supposed to reselect to 4G unless in Idle or in URA.
Reselections from FACH are limited due to less UE support even if the relevant feature is active.
No legacy RWR to LTE Feature is based on triggers connected with channel switching events of after CSFB immediately.
This feature is adding some robustness to all this and making it in Cell DCH state to which originally was not the case I believe.

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Is there any similar feature in nokia ran also , if anyone know please share