Non-orthogonal multiple access method based on large-scale MIMO

Abstract

The invention relates to a non-orthogonal multiple access method based on large-scale MIMO. The method comprises the following steps of step 1, determining an optimal demodulation sequence; step 2, determining received power of a user; step 3, determining optimal emission power of the user; step 4, determining a data frame structure, wherein different users accessing the same base station follow the same uplink frame structure for synchronous transmission, and the time slot length used by the user does not exceed the coherence time of a wireless channel; step 5, adopting a pilot selection way,wherein a way of obtaining a pilot frequency by the user is that each user randomly selects the pilot frequency used by the user from a given pilot frequency set independently; and step 6, making a plurality of user terminals send signals to the base station at the optimal transmitting power based on the step 4 and the step 5, and after the base station receives the signals, only estimating a multi-user composite channel at an antenna end by means of the channel hardening capability of the large-scale MIMO, and utilizing a serial interference elimination technology to finally complete the recovery of all user signals.

Description

technical field [0001] The invention relates to the technical fields of wireless communication, massive MIMO system and multiple access, and in particular to a non-orthogonal multiple access method based on massive MIMO. Background technique [0002] Orthogonal Multiple Access Technology: Traditional communication systems are based on Orthogonal Multiple Access (OMA) technology. These technologies first divide wireless resources, and then allocate one or more Orthogonal resources in a domain are allocated to different users. Among them, the orthogonality of resources determines the orthogonality between user signals, so that multiple users can complete data transmission without interfering with each other, thereby simplifying the design of the base station receiver. [0003] Disadvantages of Orthogonal Multiple Access Technology: In the context of massive wireless devices in future networks, especially the Internet of Things, the limitations of traditional Orthogonal Multip...

AI Technical Summary

Problems solved by technology

[0003] Disadvantages of Orthogonal Multiple Access Technology: In the context of massive wireless devices in future networks, especially the Internet of Things, the limitations of traditional Orthogonal Multiple Access solutions are gradually emerging

[0005] Disadvantages of non-orthogonal multiple access technology based on spreading code domain: For this non-orthogonal multiple access scheme based on spreading code domain, the time-frequency resources required by a specific transmission block (Transmission Block, TB) will be It is several times the time-frequency resources required in traditional orthogonal multiple access, so more time-frequency resources are occupied. It can be said that it is a method of exchanging more time-frequency resources for transmission efficiency

[0007] Disadvantages of non-orthogonal multiple access technology (NOMA) based on the power domain: a major challenge for 5G mobile communications in the future is the surge in the number of connections in the uplink direction, while the traditional NOMA mainly studies the transmission problem in the downlink direction, and concentrates on Multiplexing in a single power domain, so how to use NOMA to solve the concurrent access of a large number of uplink terminals is an unsolved problem

However, there is still a lack of relevant solutions for how to make NOMA technology suitable for massive MIMO scenarios to obtain higher user access.

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