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PLL DEMODULATION TECHNIQUE FOR M-RAY POSITION PHASE SHIFT KEYING 被引量:10
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作者 Qi Chenhao Wu Lenan 《Journal of Electronics(China)》 2009年第3期289-295,共7页
The paper presents a kind of transmission system which employs M-ary Position Phase Shift Keying(MPPSK) to send data and Phase Locked Loop(PLL) based techniques for data retrieve.With a single PLL, MPPSK demodulation ... The paper presents a kind of transmission system which employs M-ary Position Phase Shift Keying(MPPSK) to send data and Phase Locked Loop(PLL) based techniques for data retrieve.With a single PLL, MPPSK demodulation is achieved, as well as carrier recovery and symbol synchronization.Firstly, MPPSK modulation method is briefly introduced.2PPSK's PSD expression is given with its optimization result.Orthogonal Phase Detector(PD) and static threshold are used for the purpose of wider phase range and simplicity in demodulation.The data rate is alterable, which is 4.65 kbps for 2PPSK and 9.3 kbps for 4PPSK in the paper.Then some indicative comparisons in Signal to Noise Ratio Symbol Error Rate(SNR-SER) are made among 2PPSK, 3PPSK and 4PPSK, of which 4PPSK has proved to be optimal in ten slots each symbol conditions.And finally, it is demonstrated by system simulations that lower than 10-4 Symbol Error Rate(SER) performance can be obtained at 13 dB symbol SNR. 展开更多
关键词 phase Locked Loop (PLL) M-ary Position phase shift keying (MPpsk) phase Detector (PD) Power Spectrum Density (PSD)
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Multiple phase detector of M-ary phase shift keying symbols in code division multiple access systems 被引量:1
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作者 QUAN Zhi 《Journal of Central South University》 SCIE EI CAS 2011年第4期1080-1086,共7页
A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it w... A novel iterative technique, the phase descent search detection was proposed. This technique constrained the solution (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols to have a unit magnitude and it was based on coordinate descent iterations where coordinates were the unknown symbol phases. The PDS algorithm, together with a descent local search (also implemented as a version of the PDS algorithm), was used multiple times with different initializations in a proposed multiple phase detector; the solution with the minimum cost was then chosen as the final solution. The simulation results show that for highly loaded multiuser scenarios, the proposed technique has a detection performance that is close to the single-user bound. The results also show that the multiple phase detector allows detection in highly overloaded scenarios and it exhibits near-far resistance. In particular, the detector has a performance that is significantly better, and complexity that is significantly lower, than that of the detector based on semi-definite relaxation. 展开更多
关键词 coordinate descent COMPLEXITY M-ary phase shift keying (M-psk) multiuser detection quadratic optimization semi-definite relaxation
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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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Adaptive compensating method for Doppler frequency shift using LMS and phase estimation 被引量:7
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作者 Jing Qingfeng Guo Qing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期913-919,共7页
The novel compensating method directly demodulates the signals without the carrier recovery processes, in which the carrier with original modulation frequency is used as the local coherent carrier. In this way, the ph... The novel compensating method directly demodulates the signals without the carrier recovery processes, in which the carrier with original modulation frequency is used as the local coherent carrier. In this way, the phase offsets due to frequency shift are linear. Based on this premise, the compensation processes are: firstly, the phase offsets between the baseband neighbor-symbols after clock recovery is unbiasedly estimated among the reference symbols; then, the receiving signals symbols are adjusted by the phase estimation value; finally, the phase offsets after adjusting are compensated by the least mean squares (LMS) algorithm. In order to express the compensation processes and ability clearly, the quadrature phase shift keying (QPSK) modulation signals are regarded as examples for Matlab simulation. BER simulations are carried out using the Monte-Carlo method. The learning curves are obtained to study the algorithm's convergence ability. The constellation figures are also simulated to observe the compensation results directly. 展开更多
关键词 Doppler frequency shift least mean square minimum phase shift keying unbiased estimation Matlab simulation.
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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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基于单PD直接检测Twin-SSB-QPSK信号的光纤通信系统 被引量:1
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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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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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Round-robin differential quadrature phase-shift quantum key distribution 被引量:1
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作者 Chun Zhou Ying-Ying Zhang +3 位作者 Wan-Su Bao Hong-Wei Li Yang Wang Mu-Sheng Jiang 《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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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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基于匹配滤波域的PSK雷达信号有源干扰识别算法
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作者 常宇阳 余建宇 《电声技术》 2024年第6期121-128,共8页
针对复杂电磁环境下相位编码(Phase Shift Key,PSK)信号干扰识别问题,研究瞄准式干扰(Spot Jamming,SJ)、阻塞式干扰(Blocking Jamming,BJ)、线性扫频式干扰(Linear Sweep Jamming,LSJ)、灵巧噪声卷积干扰(Noise Convolution Jamming,N... 针对复杂电磁环境下相位编码(Phase Shift Key,PSK)信号干扰识别问题,研究瞄准式干扰(Spot Jamming,SJ)、阻塞式干扰(Blocking Jamming,BJ)、线性扫频式干扰(Linear Sweep Jamming,LSJ)、灵巧噪声卷积干扰(Noise Convolution Jamming,NCJ)、灵巧噪声乘积干扰(Noise Product Jamming,NPJ)、间歇采样直接转发干扰(InterruptedSampling and Direct Repeater Jamming,ISDJ)、间歇采样重复转发干扰(Interrupted-Sampling and Periodic Repeater Jamming,ISPJ)及间歇采样循环转发式干扰(Interrupted-Sampling and Cyclic Repeater Jamming,ISCJ)的匹配滤波序列,人工提取16维特征组成特征向量放入支持向量机(Support Vector Machine,SVM)进行分类识别。仿真实验表明:干噪比(Jamming Noise Ratio,JNR)为-20~30 dB至16~30 dB时,识别率随JNR的增加而提高;JNR为-2~30 dB时,识别率为94.89%;模拟JNR为-2~30 dB的真实环境时,保留8维特征参数,算法识别率可达93.62%,仅降低1.27%。 展开更多
关键词 相位编码(psk) 特征提取 匹配滤波 支持向量机(SVM)
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Passive round-robin differential-quadrature-phase-shift quantum key distribution scheme with untrusted detectors
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作者 Hongwei Liu Wenxiu Qu +3 位作者 Tianqi Dou Jipeng Wang Yong Zhang Haiqiang Ma 《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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基于Born-Jordan分布的LFM-BPSK信号的参数估计
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作者 张宏业 舒汀 何劲 《现代雷达》 CSCD 北大核心 2024年第11期22-28,共7页
对线性调频-二进制相位编码(LFM-BPSK)复合调制信号的参数估计,现有方法在低信噪比(SNR)环境下估计精度较低。针对该问题,文中推导出了LFM-BPSK信号的Born-Jordan(BJD)时频分布,分析了LFM-BPSK信号的时频特性,并提出了基于BJD时频分布... 对线性调频-二进制相位编码(LFM-BPSK)复合调制信号的参数估计,现有方法在低信噪比(SNR)环境下估计精度较低。针对该问题,文中推导出了LFM-BPSK信号的Born-Jordan(BJD)时频分布,分析了LFM-BPSK信号的时频特性,并提出了基于BJD时频分布的参数估计算法。首先,该算法在BJD时频变换的基础上使用霍夫变换对LFM-BPSK信号初始频率和调频斜率进行估计,并将二维的BJD时频变换转化为一维时域信号,通过降维后的时域信号求解码元宽度;然后,为了探寻参数估计的理论下界,文中还推导了LFM-BPSK信号参数估计的修正克拉美罗下界(MCRLB);最后,利用蒙特卡洛实验对三个参数进行了测试。仿真实验表明,文中算法在低SNR下的参数估计精度明显优于现有的算法,其性能接近MCRLB。 展开更多
关键词 线性调频-二进制相位编码复合调制信号 参数估计 修正克拉美罗下界 Born-Jordan时频分布 蒙特卡洛实验
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大频率动态微弱MPSK信号高精度测频算法
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作者 金磊 曾富华 +1 位作者 蒋友邦 王媛 《系统工程与电子技术》 EI CSCD 北大核心 2024年第12期3973-3980,共8页
传统测频方法对多进制相移键控(multiple phase shift keying,MPSK)在信号采样数据非线性变换后直接进行快速傅里叶变换,方法简单易实现,但频率测量范围小且精度差,无法适应由目标高速机动、通信距离远导致的MPSK信号频率动态大、信噪比... 传统测频方法对多进制相移键控(multiple phase shift keying,MPSK)在信号采样数据非线性变换后直接进行快速傅里叶变换,方法简单易实现,但频率测量范围小且精度差,无法适应由目标高速机动、通信距离远导致的MPSK信号频率动态大、信噪比(signal to noise ratio,SNR)低的应用场景。针对该难题,提出了一种“粗+精”处理架构的高精度测频算法,粗测状态采用功率谱加窗法粗略测量多普勒频移,精捕状态采用变化率分槽修正和滑动分组平均压缩实现多普勒频移及其变化率的双重精确测量。试验与分析结果表明,所提算法在大频率动态、低SNR条件下,多普勒频移测量精度达到Hz级、多普勒变化率测量精度达到Hz/s级,显著提高了MPSK信号在大频率动态和低SNR环境下的测频精度和检测灵敏度。 展开更多
关键词 微弱Mpsk信号 大频率动态 低信噪比 高精度测频 快速傅里叶变换
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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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Analysis and optimization of power spectrum on EBPSK modulation in throughput-efficient wireless system 被引量:6
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作者 冯熳 戚晨浩 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期143-148,共6页
In order to satisfy increasingly greater demand for the performance of communication systems, a throughput efficient wireless system based on the extended binary phase shift keying (EBPSK) modulation is presented. S... In order to satisfy increasingly greater demand for the performance of communication systems, a throughput efficient wireless system based on the extended binary phase shift keying (EBPSK) modulation is presented. Simultaneously, corresponding analysis of power spectra is also given with a brief process. The optimal waveform is proposed without useful information loss, by removing linear spectra presenting periodic components. On this basis, the reasonable definition of bandwidth is discussed, which indicates that the EBPSK belongs to the category of the ultra narrow band (UNB) throughput-efficient communication. Meanwhile, the modulation parameters' effects on bandwidth, transmission rate and transmission performance are analyzed. Results illustrate the validity of theoretical analysis and spectrum optimization. Results also prove that this UNB system can obtain good bit error rate (BER) performance with high spectra efficiency. 展开更多
关键词 extended binary phase shift keying power spectrum ultra narrow band spectra efficiency
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伪随机调制序列的CP-EBPSK通信系统 被引量:8
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作者 张宇 应鹏魁 吴乐南 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2012年第2期209-213,共5页
为了紧缩通信系统的信号频谱,减少其线谱能量,引入了一种伪随机序列调制方法.该方法通过对连续相位扩展的二元相移键控(CP-EBPSK)通信系统进行改进,使发射端键控调制时段的相位变化受控于伪随机序列,从而使CP-EBPSK调制指数的符号随机化... 为了紧缩通信系统的信号频谱,减少其线谱能量,引入了一种伪随机序列调制方法.该方法通过对连续相位扩展的二元相移键控(CP-EBPSK)通信系统进行改进,使发射端键控调制时段的相位变化受控于伪随机序列,从而使CP-EBPSK调制指数的符号随机化,同时保持CP-EB-PSK通信系统其他组成部分不变.仿真结果表明,该方法可使调制信号占用的带宽仅为CP-EB-PSK通信系统带宽的一半,显著提高了频谱的利用率.即使在-60 dB带宽的苛刻要求下,当信号载频分别为30 MHz和2.4 GHz时,伪随机序列调制的CP-EBPSK通信系统以约35 dB的信噪比为代价,获得超过200 bit/(s.Hz)的频谱利用率,大幅度紧缩了频谱,提高了系统整体性能.同时,接收机冲击滤波器的特殊滤波效果导致解调器可不受调制符号随机化的影响,从而使得解调器的解调性能基本不变. 展开更多
关键词 伪随机序列 CP-EBpsk调制 冲击滤波器 频谱利用率 误码率
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基于单脉冲相关积累的PSK信号相位编码调制规律分析 被引量:6
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作者 魏跃敏 黄知涛 +1 位作者 王丰华 姜文利 《信号处理》 CSCD 北大核心 2006年第2期281-284,共4页
文章首先研究了如何通过单脉冲相关积累从PSK信号中提取相位跳变规律,在此基础上给出了相位编码序列恢复方法。为了提高算法的性能,采用多重相关积累对算法进行了改进。根据文章中研究得到的算法进行了仿真实验,仿真结果显示,算法具有... 文章首先研究了如何通过单脉冲相关积累从PSK信号中提取相位跳变规律,在此基础上给出了相位编码序列恢复方法。为了提高算法的性能,采用多重相关积累对算法进行了改进。根据文章中研究得到的算法进行了仿真实验,仿真结果显示,算法具有良好的低信噪比环境适应能力。 展开更多
关键词 单脉冲相关积累 相位跳变 相位编码序列
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一种基于时分的EBPSK多载波实现方式 被引量:2
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作者 张鹏 吴乐南 苗圃 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第2期227-231,共5页
为了实现扩展的二元相移键控(EBPSK)调制的多载波传输,提出了一种基于时分的EBPSK多载波实现方式.首先,利用叠加原理,通过观察冲击滤波器的输出波形,分析了多路EBPSK信号间干扰的原因;然后,给出了消除信号间干扰的具体思路,即将临道信... 为了实现扩展的二元相移键控(EBPSK)调制的多载波传输,提出了一种基于时分的EBPSK多载波实现方式.首先,利用叠加原理,通过观察冲击滤波器的输出波形,分析了多路EBPSK信号间干扰的原因;然后,给出了消除信号间干扰的具体思路,即将临道信号相对延迟,使各路载波的判决区域在时间上区分开,避免判决区域的碰撞;最后,通过仿真,对比了不同时间保护间隔下基于时分的EBPSK多载波与单载波的误码率性能.仿真结果表明,时间保护间隔为0时干扰较大,多载波的误码率性能较差.在合适的时间保护间隔下,多载波的误码率性能几乎与单载波一致.基于时分的EBPSK多载波实现方式能够有效消除各路EBPSK信号间的干扰,使得多路EBPSK信号同时传输且误码率性能损失不明显. 展开更多
关键词 扩展的二元相移键控 冲击滤波器 时分 多载波 EXTENDED BINARY phase shift keying (EBpsk)
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