METHOD FOR EFFICIENT DETERMINATION OF DEEP COVERAGE OPERATION MODE FOR PLMN SELECTION IN CELLULAR IOT

The invention relates to a method for efficient determination of deep coverage operation mode for PLMN selection in cellular loT access technology. The objective of the invention to present a method that is able to limit the deep coverage PLMN scans using NB- IoT access technology to carrier frequencies where noise-limited NB- IoT deployments can be found will be solved by - preparing a list of carrier frequencies by a UE according to a list of supported RE bands to search for PLMNs on; - selecting a carrier frequency out of the list of carrier frequencies and executing a PLMN scan at a normal coverage level by receiving and processing synchronization signals as well as reading and processing a SIB1 broadcasted by an eNodeB; if the PLMN scan fails, the normal coverage level is increased step-wise into a direction of deep coverage level, wherein the method further comprises the steps : - reusing time-contiguous RF samples received during the PLMN scan on the selected carrier frequency within a power detection procedure to detect whether the carrier frequency is occupied by another RE system, whereas - the power detection procedure comprises at least three threshold detection tasks each are configured to output a Boolean value indicating whether the carrier frequency is occupied by another RE system, and as soon as one of the at least three threshold detection tasks report that the selected carrier frequency is occupied by another RF system said selected carrier frequency is skipped from PLMN scan and is stored into an internal state memory of the UE. L'invention concerne un procédé de détermination efficace de mode de fonctionnement à couverture profonde pour la sélection de PLMN dans la technologie d'accès à l'IdO cellulaire. L'objectif de l'invention est de présenter un procédé qui est capable de limiter les balayages de PLMN à couverture profonde au moyen d'une technologie d'accès NB-IdO à des fréquences porteuses dans lesquelles des déploiements NB-IdO à bruit limité peuvent être résolus par préparation d'une liste de fréquences porteuses par un UE selon une liste de bandes de RE prises en charge pour rechercher des PLMN ; - sélectionner une fréquence porteuse parmi la liste de fréquences porteuses et exécuter un balayage PLMN à un niveau de couverture normal par réception et traitement de signaux de synchronisation ainsi que lecture et traitement d'un SIB1 diffusé par un nœud B évolué (eNodeB) ; si le balayage PLMN échoue, le niveau de couverture norma