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Semi-blind Adaptive Beamforming for High-throughput Quadrature Amplitude Modulation Systems 被引量:1
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作者 Lajos Hanzo 《International Journal of Automation and computing》 EI 2010年第4期565-570,共6页
A semi-blind adaptive beamforming scheme is proposed for wireless systems that employ high-throughput quadrature amplitude modulation signalling. A minimum number of training symbols, equal to the number of receiver a... A semi-blind adaptive beamforming scheme is proposed for wireless systems that employ high-throughput quadrature amplitude modulation signalling. A minimum number of training symbols, equal to the number of receiver antenna arrayts elements, are first utilised to provide a rough initial least squares estimate of the beamformer's weight vector. A concurrent constant modulus algorithm and soft decision-directed scheme is then applied to adapt the beamformer. This semi-blind adaptive beamforming scheme is capable of converging fast to the minimum mean-square-error beamforming solution, as demonstrated in our simulation study. 展开更多
关键词 BEAMFORMING minimum mean square error quadrature amplitude modulation semi-blind adaptive algorithm constant modulus algorithm soft decision-directed scheme.
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A 3-D Polarization Quadrature Amplitude Modulation Method and Constellation Mapping 被引量:2
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作者 SUN Xuehong ZHANG Haiying +1 位作者 ZENG Zhimin GUO Caili 《China Communications》 SCIE CSCD 2015年第10期16-26,共11页
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
关键词 polarization quadrature amplitude modulation minimum euclidean distance symbol error probability 3-D constellation
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A new tracking error detection method using amplitude difference detection for signal waveform modulation multi-level discs 被引量:1
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作者 严明铭 裴京 潘龙法 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期319-323,共5页
The sub-land/sub-pit affects the characteristic of the tracking error signal which is generated by the conventional differential phase detection (DPD) method in the signal waveform modulation multi-level (SWML) re... The sub-land/sub-pit affects the characteristic of the tracking error signal which is generated by the conventional differential phase detection (DPD) method in the signal waveform modulation multi-level (SWML) read-only disc. To solve this problem, this paper proposes a new tracking error detection method using amplitude difference. Based on the diffraction theory, the amplitude difference is proportional to the tracking error and is feasible to be used for obtaining the off-track information. The experimental system of the amplitude difference detection method is developed. The experimental results show that the tracking error signal derived from the new method has better performance in uniformity and signal-to-noise ratio than that derived from the conventional DPD method in the SWML read-only disc. 展开更多
关键词 signal waveform modulation multi-level technology tracking error amplitude difference
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Pilot-added carrier-phase recovery scheme for Nyquist M-ary quadrature amplitude modulation optical fiber communication system 被引量:1
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作者 张文博 潘董威 +3 位作者 宿晓飞 张晓光 席丽霞 唐先锋 《Chinese Optics Letters》 SCIE EI CAS CSCD 2016年第2期6-10,共5页
A new two-stage carrier-phase recovery scheme using a combination of an optical pilot-aided algorithm with the crossed constellation transformation algorithm for either square-framed or non-square-framed M-level- quad... A new two-stage carrier-phase recovery scheme using a combination of an optical pilot-aided algorithm with the crossed constellation transformation algorithm for either square-framed or non-square-framed M-level- quadrature amplitude modulation (QAM) Nyquist systems is proposed. It is verified in 32- and 128-QAM systems that it can provide high linewidth tolerance with little complexity. 展开更多
关键词 Algorithms amplitude modulation modulation Optical communication Optical fibers quadrature amplitude modulation
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Optimization of Mapping Rule of Bit-Interleaved Turbo Coded Modulation with 16QAM 被引量:1
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作者 费泽松 杨宇 +1 位作者 刘林南 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2005年第1期18-21,共4页
Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding perfor... Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation. 展开更多
关键词 binary Turbo coded modulation quadrature amplitude modulation (QAM) mapping rule in-phase and quadrature (I-Q) coded modulation
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Experimental performance evaluation of quadrature amplitude modulation signal transmission in a silicon microring 被引量:2
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作者 Chengcheng Gui Jian Wang 《Photonics Research》 SCIE EI 2016年第5期168-172,共5页
We comprehensively characterize the transmission performance of m-ary quadrature amplitude modulation(m-QAM) signals through a silicon microring resonator in the experiment. Using orthogonal frequency-division multipl... We comprehensively characterize the transmission performance of m-ary quadrature amplitude modulation(m-QAM) signals through a silicon microring resonator in the experiment. Using orthogonal frequency-division multiplexing based on offset QAM(OFDM/OQAM) which is modulated with m-QAM modulations, we demonstrate low-penalty data transmission of OFDM/OQAM 64-QAM, 128-QAM, 256-QAM, and 512-QAM signals in a silicon microring resonator. The observed optical signal-to-noise ratio(OSNR) penalties are 1.7 dB for 64-QAM,1.7 dB for 128-QAM, and 3.1 dB for 256-QAM at a bit-error rate(BER) of 2 × 10^(-3) and 3.3 dB for 512-QAM at a BER of 2 × 10^(-2). The performance degradation due to the wavelength detuning from the microring resonance is evaluated, showing a wavelength range of ~0.48 nm with BER below 2 × 10^(-3). Moreover, we demonstrate data transmission of 191.2-Gbit/s simultaneous eight wavelength channel OFDM/OQAM 256-QAM signals in a silicon microring resonator, achieving OSNR penalties less than 2 dB at a BER of 2 × 10^(-2). 展开更多
关键词 QAM Experimental performance evaluation of quadrature amplitude modulation signal transmission in a silicon microring OSNR BER OFDM WDM
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AN IMPROVED AND EFFICIENT DETECTION SCHEME FOR V-BLAST SYSTEMS WITH QAM MODULATION 被引量:1
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作者 Lin Huajiong Tang Youxi Shao Shihai 《Journal of Electronics(China)》 2008年第5期588-594,共7页
The paper proposed an improved Ordered Successive Interference Cancellation(OSIC) detection scheme for V-BLAST systems with square/rectangular Quadrature Amplitude Modulation(QAM) modulation.It utilizes an equivalent ... The paper proposed an improved Ordered Successive Interference Cancellation(OSIC) detection scheme for V-BLAST systems with square/rectangular Quadrature Amplitude Modulation(QAM) modulation.It utilizes an equivalent real-valued vector expression of relationship between transmit signals and received signals,exploits the constellation's product-form structure and can eventually make the order,in which components of the transmit signals vector are extracted,more "optimal" in some sense.Thereby,it can offer an improved error probability as compared to the conventional OSIC detection scheme.In addition,the paper also proposes an efficient projection al-gorithm to calculate nulling vectors in a simple recursive fashion in order to avoid the vast increase of complexity,which is due to the fact that the original complex N -dimensional data vector and M×N channel matrix are transformed into a real 2N -dimensional data vector and a real 2M ×2N channel matrix respectively.A scrutinous complexity analysis shows that the complexity increases by only 33% as compared to the conventional scheme. 展开更多
关键词 Multiple-Input Multiple-Output (MIMO) Ordered Successive Interference Cancellation (OSIC) quadrature amplitude modulation (QAM) Vertical Bell Labs Architecture of Layered Space-Time (V-BLAST)
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10 Gb/s 16-quadrature amplitude modulation signal delivery over a wireless fiber system by using a directly modulated laser for electrical/optical conversion
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作者 赵伦 余建国 《Chinese Optics Letters》 SCIE EI CAS CSCD 2015年第6期1-4,共4页
We propose and experimentally demonstrate a novel scheme to realize electrical/optical (E/O) conversion on the receiver side of a wireless fiber integration system at the W band. At the receiver, a directly modulate... We propose and experimentally demonstrate a novel scheme to realize electrical/optical (E/O) conversion on the receiver side of a wireless fiber integration system at the W band. At the receiver, a directly modulated laser (DML) is used to realize E/O conversion. The received 85 GHz wireless millimeter-wave (mm-wave) signal is first down-converted into a 10 GHz electrical intermediate-frequency (IF) signal to overcome the insufficient band- width of the subsequent DML. Then, two cascaded electrical amplifiers (EAs) are employed to boost the elec- trical IF signal before it is used to drive a DML. By using this scheme, we transmit a 10 Gb/s 16 quadrature amplitude modulation (16QAM) signal over a 10 m wireless link, and then deliver it over a 2 km single-mode fiber-28 (SMF-28) wire link with a bit error ratio (BER) that is less than the hard-decision forward error correction threshold of 3.8× 10^-3. Our experimental results show that the DML is good device to be used for the E/O conversion of a 16OAM signal. 展开更多
关键词 Detector circuits Error correction Millimeter waves modulation Optical communication Oscillators (electronic) quadrature amplitude modulation Single mode fibers
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Iterative Demodulation and Decoding Scheme with 16 QAM
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作者 刘林南 匡镜明 +1 位作者 李鸣 费泽松 《Journal of Beijing Institute of Technology》 EI CAS 2006年第3期311-315,共5页
Iterative demodulation and decoding scheme is analyzed and modulation labeling is considered to be one of the crucial factors to this scheme. By analyzing the existent mapping design criterion, four aspects are found ... Iterative demodulation and decoding scheme is analyzed and modulation labeling is considered to be one of the crucial factors to this scheme. By analyzing the existent mapping design criterion, four aspects are found as the key techniques for choosing a label mapping. Based on this discovery, a novel mapping design criteflon is proposed and two label mappings are searched according to it. Simulation results show that the performance of BICM-ID using the novel mappings is better than the former ones. The extrinsic information transfer (EXIT) chart is introduced and it is used to evaluate the proposed mapping design criteria. 展开更多
关键词 bit-interleaved coded modulation with iterative decoding (BICM-ID) 16 quadrature amplitude modulation (16QAM) design criteria extrinsic information
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Enhanced quadrature signaling-based cooperative transmission with full rate and full diversity
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作者 芦涛 葛建华 +1 位作者 杨烨 高洋 《Journal of Central South University》 SCIE EI CAS 2014年第5期1881-1886,共6页
Quadrature signaling-based cooperative transmission is an efficient and simple scheme to obtain spatial diversity.However,this scheme causes date rate loss compared with direct transmission.In this work,our focus is o... Quadrature signaling-based cooperative transmission is an efficient and simple scheme to obtain spatial diversity.However,this scheme causes date rate loss compared with direct transmission.In this work,our focus is on recovering from the data rate loss while simultaneously achieving spatial diversity.Particularly,an enhanced quadrature signaling-based cooperative scheme was designed,which can realize full-rate transmission by using the signal space diversity(SSD)technique.Then,accurate bit error rate(BER)expression for the full-rate scheme was derived over independent and non-identically distributed(INID)Rayleigh fading channels.Specifically,a closed-form BER expression is obtained,which is quite tight over the whole SNR range,and thus allows for rapid and efficient evaluation of system performance under various channel conditions.Moreover,an asymptotic approximation of the BER was derived to show that the full-rate scheme can achieve full diversity.Simulation results verify the tightness of the analysis and show that the full-rate scheme significantly outperforms the traditional quadrature signaling-based scheme by about 2 dB with the same complexity order. 展开更多
关键词 bit error rate cooperative diversity quadrature amplitude modulation signal space diversity
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Turbo-Coded Modulation of EVRC Speech Encoder with Unequal Error Protection for Fading Channels
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作者 阿哈麦德 潘志文 +1 位作者 高西奇 尤肖虎 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期150-156,共7页
The Enhanced Variable Rate Codec (EVRC) is a standard for the Speech Service Option 3 for Wideband Spread Spectrum Digital System, which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Persona... The Enhanced Variable Rate Codec (EVRC) is a standard for the Speech Service Option 3 for Wideband Spread Spectrum Digital System, which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Personal Communications Systems). This paper investigated the combination of turbo codes with Unequal Error Protection (UEP) and 16-QAM modulation for EVRC codec of Rate 1 to get power and bandwidth efficient coding scheme. The results show that the UEP system outperforms the Equal Error Protection (EEP) one by 1.45 dB at BER of 10 -5. 展开更多
关键词 enhanced variable rate codec (EVRC) turbo codes unequal error protection (UEP) quadrature amplitude modulation (QAM)
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基于JDA-BP网络的MQAM信号调制识别
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作者 张承畅 李晓梦 +3 位作者 李吉利 王艺培 黄彦豪 罗元 《实验技术与管理》 CAS 北大核心 2024年第5期31-37,共7页
针对小样本条件下由信号调制识别准确率低和信道环境变化导致调制识别网络性能下降的问题,提出了一种基于联合分布适配-反向传播神经网络(JDA-BP)调制识别方法。通过改变信道环境生成概率分布不同的多进制正交振幅调制(MQAM)信号,提取M... 针对小样本条件下由信号调制识别准确率低和信道环境变化导致调制识别网络性能下降的问题,提出了一种基于联合分布适配-反向传播神经网络(JDA-BP)调制识别方法。通过改变信道环境生成概率分布不同的多进制正交振幅调制(MQAM)信号,提取MQAM信号的瞬时统计特征和高阶累积量组成样本,构建3个概率分布不同的数据集,使用联合分布适配(JDA)算法缩小数据集间的特征差异,并将适配后的数据集送入BP神经网络进行训练和测试。对比实验表明,在目标域为小样本的条件下,该文方法针对源域和目标域概率分布不同的情况,能有效地减小概率分布距离,信号调制识别平均准确率可达73.25%;相比于比未使用JDA-BP方法,调制识别准确率平均提高了6.80%。 展开更多
关键词 联合分布适配 多进制正交振幅调制 调制识别 反向传播神经网络
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基于锁模光学频率梳的高速数据传输 被引量:1
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作者 刘琪华 梅佳雪 +2 位作者 王金栋 张福民 曲兴华 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第4期178-185,共8页
大数据时代网络数据流量的爆炸式增长给通信系统的容量和数据传输速率带来极大的挑战.本文基于锁模光学频率梳的宽光谱范围和高相位相干性提出了一种高频正交幅度调制信号生成方法,通过电光调制器对光学频率梳进行幅度相位整形并下变频... 大数据时代网络数据流量的爆炸式增长给通信系统的容量和数据传输速率带来极大的挑战.本文基于锁模光学频率梳的宽光谱范围和高相位相干性提出了一种高频正交幅度调制信号生成方法,通过电光调制器对光学频率梳进行幅度相位整形并下变频至射频域,生成携带编码信息的高速、高阶、低相位噪声的调制信号,再结合锁模光学频率梳窄线宽、多波长的特性,仅使用单个激光器即可实现基于波分复用技术的大规模并行高速通信.仿真验证了该方案的可行性,随后在100 m的自由空间光链路中使用光子微波信号进行16元正交幅度调制通信实验,实现了误码率低于10^(–6)的14 Gbit/s数据传输. 展开更多
关键词 锁模光学频率梳 微波光子学 空间光通信 正交幅度调制
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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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基于轻量化RF算法的高阶QAM信号OSNR估计方法
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作者 张明烨 欧洺余 +1 位作者 倪钱 朱宏娜 《光通信技术》 北大核心 2024年第3期64-67,共4页
针对光信噪比(OSNR)估计复杂度高、计算量大的问题,提出了一种基于轻量化随机森林(RF)算法的高阶正交幅度调制(QAM)信号OSNR估计方法。该方法通过将不同OSNR的高阶QAM信号映射为不同的星座图数据集,并利用这些数据集来训练RF模型,从而实... 针对光信噪比(OSNR)估计复杂度高、计算量大的问题,提出了一种基于轻量化随机森林(RF)算法的高阶正交幅度调制(QAM)信号OSNR估计方法。该方法通过将不同OSNR的高阶QAM信号映射为不同的星座图数据集,并利用这些数据集来训练RF模型,从而实现OSNR的快速估计。仿真结果表明:采用基于轻量化RF算法估计64QAM和128QAM信号的OSNR,在系统OSNR真实值为5~30 d B时,2种调制格式的OSNR估计准确率均接近100%;64QAM信号OSNR估计值的平均绝对误差(MAE)为0.08 d B,128QAM的MAE为0.12 d B,比基于长短期记忆(LSTM)算法的信号OSNR估计结果更准确。 展开更多
关键词 光纤通信 随机森林 光信噪比 高阶正交幅度调制
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Neural network equalization based on delta-sigma modulation
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作者 刘博 任建新 +3 位作者 吴翔宇 陈帅东 毛雅亚 赵利 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第4期8-13,共6页
We propose a neural network equalization delta-sigma modulation(DSM)technique.After performing DSM on the multiorder quadrature amplitude modulation(QAM)orthogonal frequency division multiplexing(OFDM)signal at the tr... We propose a neural network equalization delta-sigma modulation(DSM)technique.After performing DSM on the multiorder quadrature amplitude modulation(QAM)orthogonal frequency division multiplexing(OFDM)signal at the transmitting end,neural network equalizer technology is used in the digital signal processing at receiving end.Applying this technology to a 4.6 km W-band millimeter wave system,it is possible to achieve a 1 Gbaud 8192-QAM OFDM signal transmission.The data rate reached 23.4 Gbit/s with the bit error rate at 3.8×10^(-2),lower than soft-decision forward-error correction threshold(4×10^(-2)). 展开更多
关键词 multi-order quadrature amplitude modulation W-BAND delta-sigma modulation neural network equalization nonlinear compensation
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A novel dynamic step size LMS optimization scheme for interference reducing in FBMC-QAM
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作者 DONG Qiyang MA Tianming +1 位作者 JIANG Xiaoxiao MA Honglei 《High Technology Letters》 EI CAS 2024年第3期290-296,共7页
Filter bank multicarrier quadrature amplitude modulation(FBMC-QAM)will encounter inter-ference and noise during the process of channel transmission.In order to suppress the interference in the communication system,cha... Filter bank multicarrier quadrature amplitude modulation(FBMC-QAM)will encounter inter-ference and noise during the process of channel transmission.In order to suppress the interference in the communication system,channel equalization is carried out at the receiver.Given that the con-ventional least mean square(LMS)equilibrium algorithm usually suffer from drawbacks such as the inability to converge quickly in large step sizes and poor stability in small step sizes when searching for optimal weights,in this paper,a design scheme for adaptive equalization with dynamic step size LMS optimization is proposed,which can further improve the convergence and error stability of the algorithm by calling the Sigmoid function and introducing three new parameters to control the range of step size values,adjust the steepness of step size,and reduce steady-state errors in small step sta-ges.Theoretical analysis and simulation results demonstrate that compared with the conventional LMS algorithm and the neural network-based residual deep neural network(Res-DNN)algorithm,the adopted dynamic step size LMS optimization scheme can not only obtain faster convergence speed,but also get smaller error values in the signal recovery process,thereby achieving better bit error rate(BER)performance. 展开更多
关键词 filter bank multicarrier quadrature amplitude modulation(FBMC-QAM) adap-tive equalization least mean square(LMS) dynamic step size
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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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基于自适应联合调制的massive MIMO-OFDM相位噪声消除方案
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作者 聂尧 吴思睿 +2 位作者 周心雨 范祥林 吴欢 《电声技术》 2024年第6期142-146,共5页
极化状态是信号的固有属性,具有对相位噪声不敏感的特性,利用极化状态承载信息的极化调制能消除相位噪声。但极化调制需要2根天线发送和接收,在相位噪声功率较小或无相位噪声时,遍历容量性能较差。为解决此问题,提出一种自适应联合调制... 极化状态是信号的固有属性,具有对相位噪声不敏感的特性,利用极化状态承载信息的极化调制能消除相位噪声。但极化调制需要2根天线发送和接收,在相位噪声功率较小或无相位噪声时,遍历容量性能较差。为解决此问题,提出一种自适应联合调制方案。该方案结合了正交振幅调制(Quadrature Amplitude Modulation,QAM)和极化调制,并通过自适应调整QAM调制和极化调制阶数的方法,提升不同相位噪声功率时的遍历容量。仿真结果表明,该方案的遍历容量性能优于极化调制和QAM调制方案。 展开更多
关键词 极化调制 正交振幅调制(QAM) 联合调制 遍历容量 相位噪声
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一种5G FBMC-16QAM抗干扰系统仿真研究
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作者 李明辉 《天津科技》 2024年第3期36-39,共4页
为了解决5G通信系统中存在的干扰问题,提出一种将多载波技术(FBMC)与正交幅度调制(QAM)技术相结合的方法,可以更好地解决相邻子载波干扰问题,并提高功率效率、降低带外衰减。进而设计一种基于5G FBMC系统的16QAM调制解调器,并通过星座图... 为了解决5G通信系统中存在的干扰问题,提出一种将多载波技术(FBMC)与正交幅度调制(QAM)技术相结合的方法,可以更好地解决相邻子载波干扰问题,并提高功率效率、降低带外衰减。进而设计一种基于5G FBMC系统的16QAM调制解调器,并通过星座图和FBMC-16QAM调制解调数据的误码率仿真曲线进行分析与比较,结果表明:随着信噪比的增加,误码率逐渐降低。此外,在信噪比相同的情况下,随着进制数的增加,误码率也逐渐增加。 展开更多
关键词 多载波技术(FBMC) 正交幅度调制(QAM) 抗干扰
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