Multi-user random access method and system, and base station

Abstract

The embodiment of the invention provides a multi-user random access method and system utilizing angle domain cluster sparse characteristics, and a base station. The method comprises the following steps: 1, a base station side receives a signal Q sent to a base station when equipment of a user side gets access; 2, the base station side processes the received signals, wherein the step 2 specificallycomprises: performing Fourier transform Y = QW = AHW + ZW = AX + N on a received signal Q so as to convert a system model to a multi-antenna virtual angle domain, wherein the matrix W represents a discrete Fourier transform matrix, X = HW is a channel information matrix of an angle domain, n=ZW; and 3, the base station side performs pilot frequency detection and conflict resolution according to the processed signals.

Description

technical field [0001] The present invention relates to the communication field, in particular to a multi-user random access method, base station and system. Background technique [0002] As one of the three major scenarios of the fifth-generation mobile communication system (fifth-generation, 5G), MMTC has the characteristics of a large number of devices, small data packet transmission, low mobility and low activity, and is a sparsity communication scene. However, the traditional grant-based and contention-based random access methods have cumbersome signaling interaction procedures, which not only cause excessive delays, but also cause the overhead of control information to be relatively large for small data packets of MMTC. Large, it will also cause a waste of spectrum resources. [0003] Unauthorized multi-user access technology based on Compressive Sensing (CS) is a direction to solve this problem. The core idea of ​​CS is to project a sparse or compressible high-dime...

AI Technical Summary

Problems solved by technology

[0005] 1) The density of future IoT devices will surge (10 6 Taiwan / km 2 ), even assigning non-orthogonal pilots to each user is still difficult to support such a large number of devices;

[0006] 2) User mobility leads to frequent handovers, which makes it difficult to allocate pilots in advance. Therefore, CS-based non-contention random access is only applicable to scenarios where users have low mobility, and the system has low scalability.

[0007] 3) If contention-based random access is used, it will bring conflict problems when multiple users choose the same pilot

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