Narrowband Internet of Things NB-IoT random access method based on non-orthogonal technology

Abstract

The invention provides a narrowband Internet of Things NB-IoT random access method based on the non-orthogonal technology. The narrowband Internet of Things NB-IoT random access method is applied to anarrowband Internet of Things random access method and is used for solving the problem of low random access success rate. The method comprises the following steps: 1-3, sending Msg1; 4, detecting, bya base station, multi-preamble of collision based on geographical distribution and transmitting RAR (that is, Msg2) with multiple users; 5, detecting, by a terminal, RAR; 6, estimating, by a user, TAby using an NPRS signal; 7, obtaining, by the user, RAR information, searching a TA value closest to the TA of the current user in the RAR, and obtaining corresponding Temp C-RNTI and Power BO; 8, transmitting Msg3, and opening a contention resolution timer CR; 9, separating the users based on the SIC technology; and 10-11, sending Msg4, and performing conflict resolution. According to the narrowband Internet of Things NB-IoT random access method, the multi-preamble detection and RAR reception are achieved by using the spatial distribution features of the user, the Msg3 is transmitted by using the non-orthogonal technology, the user separation is performed on the base station side, thereby effectively reducing the probability of preamble retransmission, improving the system capacity, andsolving the network congestion problem caused by large-scale connection of the NB-IoT system.

Description

technical field [0001] The invention belongs to the technical field of mobile communication, and in particular relates to a random access mechanism of a Narrowband Internet of Things (NB-IoT) based on a non-orthogonal technology. It is used to alleviate the network congestion problem caused by the excessive number of users in the NB-IoT network. Background technique [0002] NOMA is a typical non-orthogonal multiple access technology only applied in the power domain, and it is also the simplest one among all non-orthogonal multiple access technologies. Because NOMA adopts the simple linear superposition of multiple user signal power domains, it has little impact on other existing mature multiple access technologies and mobile communication standards. In NOMA technology, although the time domain and frequency domain corresponding to the time-domain and frequency-domain resource units may also adopt an orthogonal scheme, since each resource unit carries multiple non-orthogona...

AI Technical Summary

Problems solved by technology

In NOMA technology, although the time domain and frequency domain corresponding to the time-domain and frequency-domain resource units may also adopt an orthogonal scheme, since each resource unit carries multiple non-orthogonal user signals, it is necessary to distinguish the user signals in the same resource unit. Different users can only use other technologies

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