Fecha de publicación: 03/11/2022 Fuente: Wipo "IOT" The present application relates to the field of communications, and in particular to a data transmission method for an NB-IOT end, and an NB-IOT chip, an NB-IOT device, an NB-IOT communication system and a computer-readable storage medium. The method comprises: when an NRSRP measured by an NB-IOT end is greater than or equal to a first NRSRP threshold value and an SINR measured by the NB-IOT end is less than or equal to a first SINR threshold value, the NB-IOT end sending, under the configuration of an ECL being 1 or 2, a random access preamble to a base station, such that a UE establishes a connection with the base station. The configuration of an ECL is determined on the basis of a measured NRSRP and a measured SINR, such that the problem of data transmission being time-consuming is ameliorated, thereby improving user experience.