Interference avoidance and secure transmission method based on signal alignment for use in collaborative device-to-device (D2D) system

Abstract

The invention discloses an interference avoidance and secure transmission method based on signal alignment for use in a collaborative device-to-device (D2D) system. The method comprises the following steps that: a base station (SB), a user D<1>, a user D<2> and a cellular user (CU) transmit signal constellation points out after signal constellation rotation firstly during information transmission; and every collaborative transmission between a D2D subsystem and a cellular subsystem consists of two stages, wherein at a first stage, the BS, the CU and the user D<2> transmit respective signals to the user D<1> respectively; and at a second stage, the user D<1> forwards a composite signal consisting of the signal transmitted by the BS and the signal transmitted by the CU to realize bilateral information transmission between the CU and the BS, and meanwhile, the user D<1> transmits a signal needing to be transmitted of the user D<1> to the user D<2>. Through adoption of the method, the security of the collaborative D2D system can be enhanced effectively, and the symbol error rate of the collaborative D2D system is lowered.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and relates to an interference avoidance and secure transmission method based on signal alignment in a cooperative D2D system. Background technique [0002] With the continuous emergence of new applications such as mobile multimedia, social networking, and Internet of Vehicles, Device-to-Device (D2D) technology has emerged as the times require, and is considered to be one of the key technologies of the next-generation cellular network. In a cellular system supporting D2D communication, the direct link between devices and the transmission link between cellular users share the same frequency spectrum. Therefore, how to achieve effective interference management is crucial to improving the performance of D2D communication. Existing interference management schemes mainly use power control, resource allocation and signal processing techniques to eliminate or reduce the impact of interfer...

AI Technical Summary

Problems solved by technology

The disadvantages of these two strategies are: limited by the double-hop characteristics of relay transmission and node half-duplex constraints, it is difficult to improve the spectral efficiency of D2D transmission and cellular transmission

First of all, the signal received by any terminal includes the signal it needs and the signal sent to other users, so the system is limited by interference, which will cause a serious bit error platform, resulting in a system whose symbol error rate cannot follow the signal. Decrease with increasing noise ratio

Second, in practical applications, any user has data confidentiality requirements. The data of cellular users needs to be kept secret from D2D users to ensure the privacy of their information transmission, and the data of D2D users also needs to be kept private from cellular users. However, In the above cooperative two-way transmission strategy, any node can access (receive) data from any other terminal, which leads to the problem of information security

According to the survey, there is no related work to solve the above two problems in the cooperative D2D communication system

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