Is Blind Handover possible in LTE?

I have one query: is blind HO possible in LTE?
I mean without any event triggered.
Network sending rrc connection reconfiguration message with target pci info.


This is flash CSFB.

Do you mean blind HO flash CSFB?

Blind redirection CSFB is R8, RRC release just contain UMTS freq.
Flash CSFB is R9, with freq + pci + sib.

For Huawei, I think you should check HO_U2L_CONN_PRIO_Switch
To ensure blind redirection, this should be off.

A3 based HO is like blind HO, No?
If you HO UE without any consideration where it would go, that’s just Blind Ho.

I mean without any event triggered, i.e. my UE will not send any measurement report.

Blind HO works when you define colocated priority in ncell as high better than connected freq in utrannfreq, but measurement redirection is required.
Blind RSRP is -80 by default in Huawei command.

I mean HO, i.e. inter Freq HO from F1 to F2 in LTE.
Not redirection.

That won’t be Blind HO?
HO by definition is measurement based.
Other ways of moving UE are load based, core network event based, etc.

LTE PS irat to UMTS has blind HO mode.
That’s when UE report event 4G RSRP very poor (for e.g. < -120 dBm) but not found any 3G signal, eNB will force blind HO to 3G in RRC release.
So in idle UE has more time to search 3G than connected mode search, just small GAP time.

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Thanks, but it’s redirection, not HO.

Another kind is frequency-priority HO.
For e.g.: UE is in L1800 with good RSRP report for e.g. >-80, L2600 cosector is higher priority, eNB will blind HO UE to 2600.

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Better in stand alone, ec/no trigger is good as chances to drag ps call is high, as coverage will be poor in 3g but ec/no can be good.
In redirection based.

How UE report through measurement report or other mechanism?

An event which source cell RSRP higher than a threshold.

First of all, there is no blind HO kind of thing.

If target cell is known (via MR), then UE can be handovered to target cell by HO procedure, provide that UE support handover to that frequency.

If target cell is known (Via MR), but UE cannot support handover to that frequency (FGI bit indicates inter frequeny HO support) then, eNb redirect UE to that target frequency.

In case of redirection, UE can latch to any cell of targeted frequeny (Mostly it would be one for which UE send MR, but not necessary).

So practically there cannot be blind handover, but blind redirection is possible.

One exceptional case of blind handover is colocation is defined between 2 frequencies of same sector. Where UE can be asked to perform handover to target cell, but this function is rarely used in any network.


Let’s not discussed for redirection.

For HO I seen even blind HO as well.
UE will do what network command.
But someone told me it’s in specs as well.

I’m wondering if Samsung or Huawei or Ericsson support it.

Yes, it is required to mention it in order to avoid confusion.

Yes, in specs also it is there, I am taling about practical field implementations.

I mentioned only HO sorry for any confusion.