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Shaped Offset Quadrature Phase Shift Keying Based Waveform for Fifth Generation Communication
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作者 R.Ann Caroline Jenifer M.A.Bhagyaveni +1 位作者 V.Saroj Malini M.Shanmugapriya 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期2165-2176,共12页
Fifth generation(5G)wireless networks must meet the needs of emerging technologies like the Internet of Things(IoT),Vehicle-to-everything(V2X),Video on Demand(VoD)services,Device to Device communication(D2D)and many o... Fifth generation(5G)wireless networks must meet the needs of emerging technologies like the Internet of Things(IoT),Vehicle-to-everything(V2X),Video on Demand(VoD)services,Device to Device communication(D2D)and many other bandwidth-hungry multimedia applications that connect a huge number of devices.5G wireless networks demand better bandwidth efficiency,high data rates,low latency,and reduced spectral leakage.To meet these requirements,a suitable 5G waveform must be designed.In this work,a waveform namely Shaped Offset Quadrature Phase Shift Keying based Orthogonal Frequency Division Multiplexing(SOQPSK-OFDM)is proposed for 5G to provide bandwidth efficiency,reduced spectral leakage,and Bit Error Rate(BER).The proposed work is evaluated using a real-time Software Defined Radio(SDR)testbed-Wireless open Access Research Platform(WARP).Experimental and simulation results show that the proposed 5G waveform exhibits better BER performance and reduced Out of Band(OOB)radia-tion when compared with other waveforms like Offset Quadrature Phase Shift Key-ing(OQPSK)and Quadrature Phase Shift Keying(QPSK)based OFDM and a 5G waveform candidate Generalized Frequency Division Multiplexing(GFDM).BER analysis shows that the proposed SOQPSK-OFDM waveform attains a Signal to Noise Ratio(SNR)gain of 7.2 dB at a BER of 10�3,when compared with GFDM in a real-time indoor environment.An SNR gain of 8 and 6 dB is achieved by the proposed work for a BER of 10�4 when compared with QPSK-OFDM and OQPSK-OFDM signals,respectively.A significant reduction in OOB of nearly 15 dB is achieved by the proposed work SOQPSK-OFDM when compared to 16 Quadrature Amplitude Modulation(QAM)mapped OFDM. 展开更多
关键词 5G waveform orthogonal frequency division multiplexing shaped offset quadrature phase shift keying wireless open access research platform
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Semiconductor optical amplifier used as regenerator for degraded differential phase-shift keying signals
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作者 席丽霞 李建平 +2 位作者 杜树成 徐霞 张晓光 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期311-315,共5页
Phase and amplitude regeneration are necessary for degraded differential phase-shift keying communication sys- tems. This paper proposes a regenerator based on semiconductor optical amplifier for differential phase-sh... Phase and amplitude regeneration are necessary for degraded differential phase-shift keying communication sys- tems. This paper proposes a regenerator based on semiconductor optical amplifier for differential phase-shift keying signals. The key regeneration mechanism is theoretically analysed. The effectiveness of semiconductor optical amplifier based regenerator is demonstrated by comparing the bit error rate and eye diagrams before and after regeneration for 40-Cbit/s differential phase-shift keying 1080-km transmission systems. The results show that regeneration effects are very well. Bit error rate is tess than 10-12 with the regenerator. 展开更多
关键词 differential phase-shift keying REGENERATION semiconductor optical amplifier phase noise
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Analysis of the differential-phase-shift-keying protocol in the quantum-key-distribution system
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作者 焦荣珍 冯晨旭 马海强 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期915-917,共3页
The analysis is based on the error rate and the secure communication rate as functions of distance for three quantum-key-distribution (QKD) protocols: the Bennett-Brassard 1984, the Bennett Brassard Mermin 1992, an... The analysis is based on the error rate and the secure communication rate as functions of distance for three quantum-key-distribution (QKD) protocols: the Bennett-Brassard 1984, the Bennett Brassard Mermin 1992, and the coherent differential-phase-shift keying (DPSK) protocols. We consider the secure communication rate of the DPSK protocol against an arbitrary individual attack, including the most commonly considered intercept-resend and photonnumber splitting attacks, and concluded that the simple and efficient differential-phase-shift-keying protocol allows for more than 200 km of secure communication distance with high communication rates. 展开更多
关键词 differential-phase-shift keying protocol communication rate error rate
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Passive round-robin differential-quadrature-phase-shift quantum key distribution scheme with untrusted detectors
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作者 刘宏伟 屈文秀 +3 位作者 窦天琦 王吉鹏 张勇 马海强 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期208-215,共8页
In this paper, we proposed the scheme for a passive round-robin differential-phase-shift quantum key distribution(RRDPS-QKD) set-up based on the principle of Hong–Ou–Mandel interference. Our scheme requires two le... In this paper, we proposed the scheme for a passive round-robin differential-phase-shift quantum key distribution(RRDPS-QKD) set-up based on the principle of Hong–Ou–Mandel interference. Our scheme requires two legitimate parties to prepare their signal state with two different non-orthogonal bases instead of single in original protocol. Incorporating this characteristic, we establish the level of security of our protocol under the intercept-resend attack and demonstrate its detector-flaw-immune feature. Furthermore, we show that our scheme not only inherits the merit of better tolerance of bit errors and finite-sized-key effects but can be implemented using hardware similar to the measurement device independent QKD(MDI-QKD). This ensures good compatibility with the current commonly used quantum system. 展开更多
关键词 quantum key distribution round-robin-differential-phase-shift untrusted detector
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Round-robin differential quadrature phase-shift quantum key distribution
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作者 周淳 张莹莹 +3 位作者 鲍皖苏 李宏伟 汪洋 江木生 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期63-67,共5页
Recently,a round-robin differential phase-shift(RRDPS) protocol was proposed[Nature 509,475(2014)],in which the amount of leakage is bounded without monitoring the signal disturbance.Introducing states of the phas... Recently,a round-robin differential phase-shift(RRDPS) protocol was proposed[Nature 509,475(2014)],in which the amount of leakage is bounded without monitoring the signal disturbance.Introducing states of the phase-encoded Bennett-Brassard 1984 protocol(PE-BB84) to the RRDPS,this paper presents another quantum key distribution protocol called round-robin differential quadrature phase-shift(RRDQPS) quantum key distribution.Regarding a train of many pulses as a single packet,the sender modulates the phase of each pulse by one of {0,π/2,π,3π/2},then the receiver measures each packet with a Mach-Zehnder interferometer having a phase basis of 0 or π/2.The RRDQPS protocol can be implemented with essential similar hardware to the PE-BB84,so it has great compatibility with the current quantum system.Here we analyze the security of the RRDQPS protocol against the intercept-resend attack and the beam-splitting attack.Results show that the proposed protocol inherits the advantages arising from the simplicity of the RRDPS protocol and is more robust against these attacks than the original protocol. 展开更多
关键词 round-robin differential phase-shift protocol quantum key distribution intercept-resend attack beam-splitting attack
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Interactive Kalman Filtering for Differential and Gaussian Frequency Shift Keying Modulation with Application in Bluetooth 被引量:3
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作者 Mahdi N. Ali Mohamed A. Zohdy 《Journal of Signal and Information Processing》 2012年第1期63-76,共14页
Some applications are constrained only to implement low cost receivers. In this case, designers are required to use less complex and non-expensive modulation techniques. Differential Quadrature Phase Shift Keying (DQP... Some applications are constrained only to implement low cost receivers. In this case, designers are required to use less complex and non-expensive modulation techniques. Differential Quadrature Phase Shift Keying (DQPSK) and Gaussian Frequency Shift Keying (GFSK) can be non-coherently demodulated with simple algorithms. However, these types of demodulation are not robust and suffer from poor performance. This paper proposes a new method to enhance the performance of DQPSK and GFSK using Interactive Kalman Filtering (IKF) technique, in which a one Unscented Kalman Filter (UKF) and two Kalman Filters (KF) are coupled to optimize the demodulated signals. This method consists of simple but very effective algorithms without adding complexity to the demodulators comparing to other very complex methods. UKF is used in this method due to its superiority in approximating and estimating nonlinear systems and its ability to handle non-Gaussian noise environments. The proposed method has been validated by creating a MATLAB/SIMULINK Bluetooth system model, in which the IKF is integrated into the receiver, which implement both DQPSK and GFSK, and run simulation in Gaussian and Non-Gaussian noise environments. Results have shown the effectiveness of this method in optimizing the received signals, and that the UKF outperforms the Extended Kalman Filter (EKF). 展开更多
关键词 INTERACTIVE KALMAN Filtering Unscented KALMAN Filter Extended KALMAN Filter differential quadrature phase shift keying GAUSSIAN Frequency shift keying BLUETOOTH
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Influence of multi-photon pulses on practical differential-phase-shift quantum key distribution 被引量:2
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作者 赵峰 傅明星 +1 位作者 路轶群 刘颂豪 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3402-3406,共5页
The influence of multi-photon pulses on practical differcBtial-phase-shift quantum key distribution (DPS-Qt(D) is analysed. We have estimated the information which Eve obtained by PNS (photon-number splitting) at... The influence of multi-photon pulses on practical differcBtial-phase-shift quantum key distribution (DPS-Qt(D) is analysed. We have estimated the information which Eve obtained by PNS (photon-number splitting) attack and BS (beam splitting) attack. The result indicates that the PNS attack and BS attack will not limit the transmission distance as long as we select an appropriate mean photon number. Also, the maximum mean photon number under BS attack in practical DPS-QKD system and the set of practical assumptions about Eve's capabilities are presented. 展开更多
关键词 multi-photon pulses differential-phase-shift quantum key distribution PNS attack BS attack
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Lower bound for the security of differential phase shift quantum key distribution against a one-pulse-attack
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作者 李宏伟 银振强 +3 位作者 王双 鲍皖苏 郭光灿 韩正甫 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期46-50,共5页
Quantum key distribution is the art of sharing secret keys between two distant parties, and has attracted a lot of attention due to its unconditional security. Compared with other quantum key distribution protocols, t... Quantum key distribution is the art of sharing secret keys between two distant parties, and has attracted a lot of attention due to its unconditional security. Compared with other quantum key distribution protocols, the differential phase shift quantum key distribution protocol has higher efficiency and simpler apparatus. Unfortunately, the uncondi- tional security of differential phase shift quantum key distribution has not been proved. Utilizing the sharp continuity of the von Neuman entropy and some basic inequalities, we estimate the upper bound for the eavesdropper Eve's infor- mation. We then prove the lower bound for the security of the differential phase shift quantum key distribution protocol against a one-pulse attack with Devatak-Winter's secret key rate formula. 展开更多
关键词 lower bound differential phase shift quantum key distribution
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星间链路通信收发一体化系统设计
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作者 鲍爱达 候世豪 +2 位作者 郭鑫 崔鹤 张鑫哲 《计算机测量与控制》 2024年第8期280-286,共7页
随着卫星制造发射成本的降低以及全球通信需求的增加,低轨星间链路技术成为研究热点;星间链路可将多颗卫星互联,建立具有导航和通信功能的自主运行系统,可靠的通信技术是当前的研究重点;为了适应外太空具有较大多普勒频移的高动态环境,... 随着卫星制造发射成本的降低以及全球通信需求的增加,低轨星间链路技术成为研究热点;星间链路可将多颗卫星互联,建立具有导航和通信功能的自主运行系统,可靠的通信技术是当前的研究重点;为了适应外太空具有较大多普勒频移的高动态环境,设计了星间链路通信收发一体化系统;发射端采用UQPSK直接序列扩频技术,双通道架构可同时完成不同速率的导航与通信数据的发射,再运用LDPC编码技术提升数据发射速率与稳定性;接收端采用改进的PMF-FFT分段捕获算法与归一化最小和LDPC译码算法,以快速准确捕获星间信息;在FPGA硬件平台经过多次测试,该系统均可在高动态环境下,正确快速捕获到多普勒频移高达±341 kHz的信号,捕获算法时间均可保持在200 ms以内,符合实际应用中的性能需求。 展开更多
关键词 星间链路 UQPSK直接序列扩频技术 PMF-FFT LDPC FPGA
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基于单PD直接检测Twin-SSB-QPSK信号的光纤通信系统
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作者 张洪波 刘娇 +3 位作者 凌味未 张敏 万峰 蔡炬 《通信学报》 EI CSCD 北大核心 2024年第6期187-195,共9页
针对孪生单边带正交相移键控(Twin-SSB-QPSK)信号在光传输过程中的高成本问题,提出了一种在接收端采用单光电探测器(PD)直接检测Twin-SSB-QPSK信号的光纤通信系统。在接收端不需要采用光带通滤波器(OBPF)对Twin-SSB-QPSK信号的两路光单... 针对孪生单边带正交相移键控(Twin-SSB-QPSK)信号在光传输过程中的高成本问题,提出了一种在接收端采用单光电探测器(PD)直接检测Twin-SSB-QPSK信号的光纤通信系统。在接收端不需要采用光带通滤波器(OBPF)对Twin-SSB-QPSK信号的两路光单边带信号进行分离,而是利用直接检测的拍频效应,通过单PD直接检测孪生的两路光单边带QPSK信号产生相干叠加的单路16阶正交幅度调制(16QAM)信号。仿真演示了两路56 Gbit/s的QPSK信号叠加为一路112 Gbit/s的16QAM信号,并与传统的单路16QAM信号传输方案进行了仿真对比。仿真结果表明,该方案在降低系统器件要求和部署成本的同时并没有带来额外的功率代价。 展开更多
关键词 光纤通信 正交相移键控 正交幅度调制 信号合成 直接检测
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一种M进制短参考置换索引的差分混沌移位键控系统
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作者 柳粟杰 杨烈君 谢肇鹏 《半导体光电》 CAS 北大核心 2024年第3期485-492,共8页
为解决置换索引的差分混沌移位键控(PI-DCSK)通信系统存在能量效率低的问题,结合短参考技术,提出了一种M进制短参考置换索引的差分混沌移位键控(SR-PI-DCSK)系统。该系统将参考时隙的混沌序列缩短至小于半个符号周期,信息时隙将参考时... 为解决置换索引的差分混沌移位键控(PI-DCSK)通信系统存在能量效率低的问题,结合短参考技术,提出了一种M进制短参考置换索引的差分混沌移位键控(SR-PI-DCSK)系统。该系统将参考时隙的混沌序列缩短至小于半个符号周期,信息时隙将参考时隙的置换排列副本进行复制并拼接P次,在不增加PI-DCSK系统结构复杂度及维持相同的恢复比特信息所需能量的情况下,可以有效提高系统能量效率,同时提升系统的误比特率(BER)。然后,分析了SR-PIDCSK系统的能量效率,推导了其在多径瑞利衰落信道环境下的BER表达式,使用蒙特-卡罗模拟仿真验证了该理论推导的正确性。仿真结果表明,在同一条件下,所提出的系统与PI-DCSK系统相比具有更好的性能增益,这能为下一代物联网短距离通信应用提供一种混沌调制方案。 展开更多
关键词 差分混沌移位键控 短参考置换索引 能量效率
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BPSK-QPSK和QPSK-16QAM的光调制格式转换
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作者 林昭 王兴财 冯世杰 《太赫兹科学与电子信息学报》 2024年第3期309-315,共7页
信号在调制方式不同的系统之间传输时,需要对信号调制格式进行转换,而调制格式转换通常在电信号上进行,要将光信号恢复成电信号。在电信号上进行调制格式转换后,再经电光调制器变换成光信号发射。频繁的光电或电光转换通常会增加系统成... 信号在调制方式不同的系统之间传输时,需要对信号调制格式进行转换,而调制格式转换通常在电信号上进行,要将光信号恢复成电信号。在电信号上进行调制格式转换后,再经电光调制器变换成光信号发射。频繁的光电或电光转换通常会增加系统成本,针对该问题,提出了利用相干叠加在光域上实现二进制相移键控(BPSK)到正交相移键控(QPSK)以及QPSK到正交幅度调制(16QAM)的调制格式转换的方法。实验通过Optisystem软件对转换模型进行仿真,采用10 Gpbs伪随机信号作为测试信源,通过星座图观测出信号成功转换为QPSK和16QAM;并在不同光信噪比、光源线宽和信号功率下对转换模型与直接QPSK、16QAM传输模型进行误码分析对比,在相同条件下转换模型和直接传输的误码率高度保持一致,表明这种调制格式转换方法具有较高的稳定性和准确性,能够适用于不同系统间的信号传输。 展开更多
关键词 光通信 调制 二进制相移键控 正交相移键控 正交幅度调制
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Undersampled differential phase shift on-off keying for optical camera communications
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作者 Niu Liu Julian Cheng Jonathan Francis Holzman 《Journal of Communications and Information Networks》 2017年第4期47-56,共10页
OCC(Optical Camera Communication)has been proposed in recent years as a new technique for visible light communications.This paper introduces the implementation and experimental demonstration of an OCC system.Phase unc... OCC(Optical Camera Communication)has been proposed in recent years as a new technique for visible light communications.This paper introduces the implementation and experimental demonstration of an OCC system.Phase uncertainty and phase slipping caused by camera sampling are the two major challenges for OCC.In this paper,we propose a novel modulation scheme called undersampled differential phase shift on–off keying to encode binary data bits without exhibiting any flicker to human eyes.The phase difference between two consecutive samples conveys one-bit information,which can be decoded by a low-frame-rate camera receiver.Error detection techniques are introduced to enhance the reliability of the system.We present the hardware and software design of the proposed system,which is implemented with a Xilinx FPGA and a Logitech commercial camera.Experimental results demonstrate that a bit-error rate of 10−5 can be achieved with 7.15 mW received signal power over a link distance of 15 cm. 展开更多
关键词 image sensor light-emitting diode optical camera communication undersampled differential phase shift on-off keying visible light communication
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一种搭载FPGA和AD9361的软件无线电平台实现方法 被引量:2
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作者 禹永植 夏泽宇 刘宇 《应用科技》 CAS 2023年第4期90-95,共6页
为了解决传统无线电平台分立器件繁多、功能单一、开发周期长的问题,提出了一种搭载现场可编程门阵列(field programmable gate arrays,FPGA)和AD9361的软件无线电平台的实现方法。以FPGA(KINTEX-7)为主控芯片,表述了MicroBlaze嵌入式... 为了解决传统无线电平台分立器件繁多、功能单一、开发周期长的问题,提出了一种搭载现场可编程门阵列(field programmable gate arrays,FPGA)和AD9361的软件无线电平台的实现方法。以FPGA(KINTEX-7)为主控芯片,表述了MicroBlaze嵌入式软核与相应串行外设接口(serial peripheral interface,SPI)、通用输入输出(general purpose input\output,GPIO)接口以及数据接口的设计思路,并对AD9361进行了芯片配置,实现了FPGA基带模块与AD9361之间的数据交互。功能测试结果表明,此平台能够根据需求更改数据调制方式与收发通道参数配置,且具有良好的收发性能。与传统无线电平台相比,此平台具有灵活性高、通用性强等特点,能够适用于多种应用场景。 展开更多
关键词 软件无线电平台 现场可编程门阵列 宽带收发器 手动增益控制 正交相移键控 射频收发 通信频点 接收增益
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2DPSK调制与解调系统的仿真设计与分析
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作者 尚丽 刘淑芬 《智能建筑与智慧城市》 2023年第1期29-31,共3页
二进制差分相移键控(2DPSK)法能够避免2PSK信号传输中相位不确定和倒“π”缺陷,误码率极低,实际应用较广。为了更好地理解2DPSK调制和解调的原理,借助于MATLAB/Simulink仿真技术实现了2DPSK调制和解调系统的建模和分析。仿真实验表明,... 二进制差分相移键控(2DPSK)法能够避免2PSK信号传输中相位不确定和倒“π”缺陷,误码率极低,实际应用较广。为了更好地理解2DPSK调制和解调的原理,借助于MATLAB/Simulink仿真技术实现了2DPSK调制和解调系统的建模和分析。仿真实验表明,仿真结果和理论分析内容一致,验证了仿真模型的正确性。 展开更多
关键词 数字相位调制 二进制差分相移键控(2DPSK) 调制方法 解调方法 MATLAB/SIMULINK仿真
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光子灯笼模分复用系统MIMO-free高速传输实验 被引量:1
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作者 唐胜龙 武保剑 +2 位作者 严伟 文峰 赵天烽 《光子学报》 EI CAS CSCD 北大核心 2023年第1期79-87,共9页
为考察无需多输入多输出模分复用系统的高速信号传输能力,采用模式选择光子灯笼型模式复用/解复用器构建了2×100 Gb/s双偏振正交相移键控模分复用通信实验系统,系统中用到的少模偏振控制器状态可由LP_(01)和LP_(11b)两个模式信道... 为考察无需多输入多输出模分复用系统的高速信号传输能力,采用模式选择光子灯笼型模式复用/解复用器构建了2×100 Gb/s双偏振正交相移键控模分复用通信实验系统,系统中用到的少模偏振控制器状态可由LP_(01)和LP_(11b)两个模式信道的信串比参数准确表征。测试了系统误码率与信串比关系,实现两个信道纠后无误码传输的条件为信串比约大于8 dB。当两个信道的信串比分别为14.25 dB和13.81 dB时,与背对背收发系统相比,纠后无误码阈值(10^(-2))的接收光功率代价分别为1.40 dB和4.76 dB。分析了光纤衰减、偏振模色散和模式串扰对高速传输系统的影响,估算了串扰受限系统可支持的少模光纤传输距离约为30 km。 展开更多
关键词 光纤通信 模分复用 信串比 光子灯笼 双偏振正交相移键控
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SR-DCSK Cooperative Communication System with Code Index Modulation:A New Design for 6G New Radios 被引量:1
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作者 Yi Fang Wang Chen +2 位作者 Pingping Chen Yiwei Tao Mohsen Guizani 《China Communications》 SCIE CSCD 2023年第10期1-16,共16页
This paper proposes a high-throughput short reference differential chaos shift keying cooperative communication system with the aid of code index modulation,referred to as CIM-SR-DCSK-CC system.In the proposed CIM-SR-... This paper proposes a high-throughput short reference differential chaos shift keying cooperative communication system with the aid of code index modulation,referred to as CIM-SR-DCSK-CC system.In the proposed CIM-SR-DCSK-CC system,the source transmits information bits to both the relay and destination in the first time slot,while the relay not only forwards the source information bits but also sends new information bits to the destination in the second time slot.To be specific,the relay employs an N-order Walsh code to carry additional log_(2)N information bits,which are superimposed onto the SRDCSK signal carrying the decoded source information bits.Subsequently,the superimposed signal carrying both the source and relay information bits is transmitted to the destination.Moreover,the theoretical bit error rate(BER)expressions of the proposed CIMSR-DCSK-CC system are derived over additive white Gaussian noise(AWGN)and multipath Rayleigh fading channels.Compared with the conventional DCSKCC system and SR-DCSK-CC system,the proposed CIM-SR-DCSK-CC system can significantly improve the throughput without deteriorating any BER performance.As a consequence,the proposed system is very promising for the applications of the 6G-enabled lowpower and high-rate communication. 展开更多
关键词 differential chaos shift keying cooperative communication short reference code index modulation high throughput bit error rate
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一种基于最大似然的SOQPSK联合估计优化算法
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作者 夏岳隆 迟永钢 +2 位作者 杨明川 陈轶驰 武文睿 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2023年第5期22-29,共8页
为解决整形偏移正交相移键控(shaped-offset quadrature phase-shift keying,SOQPSK)信号符号定时同步算法在高精度条件下实现复杂度较高的问题,提出了一种基于最大似然的优化SOQPSK符号定时与相位同步联合估计算法。首先给出了SOQPSK-... 为解决整形偏移正交相移键控(shaped-offset quadrature phase-shift keying,SOQPSK)信号符号定时同步算法在高精度条件下实现复杂度较高的问题,提出了一种基于最大似然的优化SOQPSK符号定时与相位同步联合估计算法。首先给出了SOQPSK-MIL信号模型和该信号的相位变化规律,以及基于最大似然算法的SOQPSK信号的符号定时与相位同步联合估计算法的原理与估计结果,详细分析了该算法中不同h函数的能量差异以及其所带来的在不同简化程度下该算法的性能差距,并论证了在只采用Z_(1)^(+)和Z_(-1)^(+)参数进行估计时算法的有效性,同时针对该算法实现过程中卷积运算量大的问题,提出了一种h函数的优化处理方式,在保证h函数能量不变的前提下,对h函数进行量化,使其变为一个简单的只有0、A和-A三种幅度的三值函数,从而有效减小卷积过程的计算量,使卷积部分的计算复杂度由O(N^(2)L_(0))下降为O(NL_(0))。仿真结果表明:该算法具有估计精度高、计算复杂度低的特点,在大幅降低了算法实现复杂度的同时,维持了先前的高估计精度,改进后算法的定时误差和相位误差的估计结果的最小均方误差几乎与改进前没有差别。 展开更多
关键词 整形偏移正交相移键控 连续相位信号 符号定时 相位同步 联合估计
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根升余弦脉冲成型正交相移键控信号关键参数估计
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作者 朱航 宋伟 +2 位作者 谭铭 吕海燕 戴峥 《探测与控制学报》 CSCD 北大核心 2023年第2期73-78,共6页
针对非合作通信中根升余弦脉冲成型正交相移键控(QPSK)信号关键参数估计难度较大的问题,利用估计出的功率谱及其直方图实现对载频、符号周期的快速粗估计,在此基础上根据包络谱特点利用Chirp-Z变换估计得到符号周期的精确估计值,引入奇... 针对非合作通信中根升余弦脉冲成型正交相移键控(QPSK)信号关键参数估计难度较大的问题,利用估计出的功率谱及其直方图实现对载频、符号周期的快速粗估计,在此基础上根据包络谱特点利用Chirp-Z变换估计得到符号周期的精确估计值,引入奇异谱分析方法在信号去噪的基础上实现载频精确估计,以载频及符号周期精确估计值为基础,实现对根升余弦脉冲滚降系数的估计,并给出了基于子空间分解对信噪比和信号幅度进行估计的方法。仿真表明,该方法在较低信噪比条件下仍能达到较好的估计精度。 展开更多
关键词 根升余弦脉冲 正交相移键控信号 参数估计 功率谱 CHIRP-Z变换 奇异谱分析
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一种基于UQPSK体制的无人机数据链设计与实现
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作者 李昂阳 王曦煜 +1 位作者 牟宏伟 孔志杰 《电讯技术》 北大核心 2023年第3期342-347,共6页
无人机技术和载荷设备的不断升级,对地面站与无人机终端之间数据通信的可靠性和有效性等要素提出了更高的要求。结合传输数据流需求的非对称性,分析了非平衡四相移键控(Unbalanced Quadrature Phase Shift Keying,UQPSK)通信体制的优势... 无人机技术和载荷设备的不断升级,对地面站与无人机终端之间数据通信的可靠性和有效性等要素提出了更高的要求。结合传输数据流需求的非对称性,分析了非平衡四相移键控(Unbalanced Quadrature Phase Shift Keying,UQPSK)通信体制的优势,通过Matlab进行可行性仿真分析,并采用现场可编程门阵列(Field Programmable Gate Array,FPGA)进行实现。测试结果表明,在通信距离100 km、图像数据16 Mb/s、遥测数据51.2 kb/s的情况下,该方案能够实现小于10^(-6)的误码率。 展开更多
关键词 无人机数据链 非平衡四相移键控(UQPSK) 硬件实现 链路性能
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