为了保障时间反演正交频分复(Time reversal-orthogonal frequency division multiplex,TR-OFDM)系统的物理层安全传输,提出了一种基于四元数加密的安全传输算法。该算法主要分为3个步骤:发射端和合法接收端利用估计信道得到加密传输过...为了保障时间反演正交频分复(Time reversal-orthogonal frequency division multiplex,TR-OFDM)系统的物理层安全传输,提出了一种基于四元数加密的安全传输算法。该算法主要分为3个步骤:发射端和合法接收端利用估计信道得到加密传输过程中需要的四元数,即密钥;发射端将需要传输的比特序列做三维映射,利用四元数对三维星座点做旋转加密,调制为OFDM符号并经过时间反演处理之后发射出去;合法用户利用四元数进行解密和解调,从而获得传输的数据,而窃听者因为不知道密钥而无法获得传输信息。因此所提算法保证了系统数据传输的安全性。通过仿真证明本文所提出算法可以使窃听用户的误符号率始终保持在0.5左右;在相同信噪比下,较传统的二维调制,合法用户可以实现更低的误符号率;相较于人工噪声技术方案,本文所提算法不会影响合法用户的误符号率。展开更多
As a new three-dimensional(3-D)modulation,Polarization Quadrature Amplitude Modulation(PQAM) can be regarded as the combination of Pulse amplitude modulation(PAM) and Quadrature Amplitude Modulation(QAM) Modulation.It...As a new three-dimensional(3-D)modulation,Polarization Quadrature Amplitude Modulation(PQAM) can be regarded as the combination of Pulse amplitude modulation(PAM) and Quadrature Amplitude Modulation(QAM) Modulation.It can better improve the digital communication efficiency and reduce the Symbol error rate(SER) of the system than one-dimensional or two-dimensional modulation scheme.How to design a feasible constellation is the most concerned problem of PQAM currently.This paper first studies the relationship between the SER theoretical value of PQAM and the distribution of M and N,proposes a new M,N allocation scheme.Secondly,a new and straightforward design method of constructing higher-level 3-D signal constellations,which can be matched with the PQAM,and the constellation can divided into three different structures according to the ary for PQAM.Finally,the simulation results show that:in PQAM system,the modulation scheme and the constellation mapping scheme are proposed in this paper which can effectively reduce the system SER and improve the anti-noise performance of the system.展开更多
文摘为了保障时间反演正交频分复(Time reversal-orthogonal frequency division multiplex,TR-OFDM)系统的物理层安全传输,提出了一种基于四元数加密的安全传输算法。该算法主要分为3个步骤:发射端和合法接收端利用估计信道得到加密传输过程中需要的四元数,即密钥;发射端将需要传输的比特序列做三维映射,利用四元数对三维星座点做旋转加密,调制为OFDM符号并经过时间反演处理之后发射出去;合法用户利用四元数进行解密和解调,从而获得传输的数据,而窃听者因为不知道密钥而无法获得传输信息。因此所提算法保证了系统数据传输的安全性。通过仿真证明本文所提出算法可以使窃听用户的误符号率始终保持在0.5左右;在相同信噪比下,较传统的二维调制,合法用户可以实现更低的误符号率;相较于人工噪声技术方案,本文所提算法不会影响合法用户的误符号率。
基金supported in part by the National Natural Science Foundation of China (61561039, 61271177, and 61461044)
文摘As a new three-dimensional(3-D)modulation,Polarization Quadrature Amplitude Modulation(PQAM) can be regarded as the combination of Pulse amplitude modulation(PAM) and Quadrature Amplitude Modulation(QAM) Modulation.It can better improve the digital communication efficiency and reduce the Symbol error rate(SER) of the system than one-dimensional or two-dimensional modulation scheme.How to design a feasible constellation is the most concerned problem of PQAM currently.This paper first studies the relationship between the SER theoretical value of PQAM and the distribution of M and N,proposes a new M,N allocation scheme.Secondly,a new and straightforward design method of constructing higher-level 3-D signal constellations,which can be matched with the PQAM,and the constellation can divided into three different structures according to the ary for PQAM.Finally,the simulation results show that:in PQAM system,the modulation scheme and the constellation mapping scheme are proposed in this paper which can effectively reduce the system SER and improve the anti-noise performance of the system.