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Roaming Threshold

Viewing 9 posts - 1 through 9 (of 9 total)
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  • #63537

    Hi Engineers,
    We are doing national roaming at the locations where we don’t have coverage.What is the Minimum RxLev for an MS to start Roaming? And when an MS is moving from roaming areas to areas with Home network coverage what is the minimum RxLev for that MS to quit roaming and hence camp on the Home network??


    Ooh Dear…i’m all alone in this mess…why my operator opted national roaming instead of keep rolling out its network?? That’s why this is not common in this forum. Only me!!
    Ooh please guys, share something with me, even a sentence..just few words..


    hi jeff 🙂

    3gpp TS 22811-720 6.12

    6.12 Network selection in border areas
    A problem exists for mobile users when commuting across national borders. Whilst manual network selection may be used to ensure that the user can select the HPLMN / EHPLMN, many users use Automatic Selection mode; and the ME is only permitted to select PLMNs of a higher priority within the same country in automatic mode. This leads to the situation that, having crossed back into its home country and within HPLMN coverage, an ME might remain camped on the VPLMN in the adjacent territory.
    As a consequence, the user will be charged international roaming rates for all calls made or received until such time as he either
    (a) moves out of VPLMN coverage or
    (b) manually selects the HPLMN.

    Please have a look to this thread :

    and thanks again paraHO 🙂


    Thank you Pix,
    But my problem is within same country. Not at the country borders. We are roaming in other big operators network since ours is still young. (No coverage at some regions). Directors are on top of me now. They need an answer. Help!!


    Can you update using subscribers SIM OTA (over-the-air):

    Forbidden-PLMN (EF-FPLMN) populate the F-PLMN with those roaming operators MCC/MNC?


    Hi Jeff,

    I think you should make the following settings:

    1. Subscribers can start roaming when their received signal level is less than your network minimum access level (ACCMIN or RXLEV_MIN).

    2. An MS should quit roaming when its received signal level is greater than or equal to your network minimum access level (same as in 1).



    The received signal strength I’m referring to is the received signal strength of the home PLMN (that’s, ur network)



    i’m amazed at one thing : your bosses are pressuring you, and you just have to spend 5 minutes reading the 3GPP specs to find an answer…

    and you didn’t do it.

    so ok, i did it.
    the 3GPP 22.811 is not relevant to your case, it applies to non_3GPP reselection.
    but if you look at 3GPP 23.122, you will read this : In VPLMN Automatic and manual network selection modes
    If the MS is in a VPLMN, the MS shall periodically attempt to obtain service on its HPLMN (if the EHPLMN list is not present or is empty) or one of its EHPLMNs (if the EHPLMN list is present) or a higher priority PLMN/access technology combinations listed in “user controlled PLMN selector” or “operator controlled PLMN selector” by scanning in accordance with the requirements that are applicable to i), ii) and iii) as defined in the Automatic Network Selection Mode in subclause In the case that the mobile has a stored “Equivalent PLMNs” list the mobile shall only select a PLMN if it is of a higher priority than those of the same country as the current serving PLMN which are stored in the “Equivalent PLMNs” list. For this purpose, a value T minutes may be stored in the SIM, T is either in the range 6 minutes to 8 hours in 6 minute steps or it indicates that no periodic attempts shall be made. If no value is stored in the SIM, a default value of 60 minutes is used.

    in other words, the MS is reattempting to reselect the HPLMN every hour, by default.
    read it more in details, because i just read it quickly….



    hi pix,

    I find a very helpfull info you shared with us…

    Do you think it will be better to change this HPLMN timer to smaller value?

    I think that this will help Jeff to solve his problem if the value will be 6 min the cells will search for HPLMN after 6 min, in order to avoid national roaming!

    What do you think, is this change recommended?


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