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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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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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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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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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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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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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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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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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Maximal capacity nonorthogonal pulse shape modulation 被引量:8
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作者 Chen Zhaonan Wang Hongxing +1 位作者 Liu Xiguo Zhong Peilin 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第6期1699-1708,共10页
To improve spectral utilization of communication system, a novel nonorthogonal pulse shape modulation (NPSM) based on prolate spheroidal wave function (PSWF) is proposed. The modulation employs nonorthogonal PSWF ... To improve spectral utilization of communication system, a novel nonorthogonal pulse shape modulation (NPSM) based on prolate spheroidal wave function (PSWF) is proposed. The modulation employs nonorthogonal PSWF pulses to transmit information and it shows a higher capacity than traditional orthogonal modulations. The NPSM capacity under the constraint of finite input alphabet, which is determined by parameters of PSWF pulse, is derived. An optimiza- tion model for maximal capacity of NPSM is constructed and an exhaustive self-adapting gradient search algorithm for the model is proposed. A practical NPSM scheme with the maximal capacity is obtained by this search algorithm and it is proved to be superior to orthogonal signaling in the capacity. Our theoretical analysis is validated by numerical simulations and practical tests, and the results show that NPSM outperforms orthogonal modulations in the capacity and has a lower Peak-to-Average Power Ratio. 展开更多
关键词 capacity modulation ORTHOGONALITY Prolate spheroidal wave function quadrature amplitude modulation
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An improving energy efficiency cooperation algorithm based on Nash bargaining solution in selfish user cooperative networks
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作者 张闯 赵洪林 贾敏 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期181-187,共7页
A bandwidth-exchange cooperation algorithm based on the Nash bargaining solution (NBS) is proposed to encourage the selfish users to participate with more cooperation so as to improve the users' energy efficiency. ... A bandwidth-exchange cooperation algorithm based on the Nash bargaining solution (NBS) is proposed to encourage the selfish users to participate with more cooperation so as to improve the users' energy efficiency. As a result, two key problems, i.e. , when to cooperate and how to cooperate, are solved. For the first problem, a proposed cooperation condition that can decide when to cooperate and guarantee users' energy efficiency achieved through cooperation is not lower than that achieved without cooperation. For the second problem, the cooperation bandwidth allocations (CBAs) based on the NBS solve the problem how to cooperate when cooperation takes place. Simulation results show that, as the modulation order of quadrature amplitude modulation (QAM) increases, the cooperation between both users only occurs with a large signal-to-noise ratio (SNR). Meanwhile, the energy efficiency decreases as the modulation order increases. Despite all this, the proposed algorithm can obviously improve the energy efficiency measured in bits-per-Joule compared with non-cooperation. 展开更多
关键词 cooperation algorithm Nash bargaining solution(NBS) resource-exchange quadrature amplitude modulation(QAM)
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A 20.8-Gbps Dual-Carrier Wireless Communication Link in 220-GHz Band 被引量:4
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作者 Yinian Feng Bo Zhang +7 位作者 Chen Zhi Ke Liu Weilong Liu Fang Shen Chuanqi Qiao Jicong Zhang Yong Fan Xiaobo Yang 《China Communications》 SCIE CSCD 2021年第5期210-220,共11页
With the successful demonstration of terahertz(THz)high-speed wireless data transmission,the THz frequencies are now becoming a worth candidate for post-5G wireless communications.On the other hand,to bring THz commun... With the successful demonstration of terahertz(THz)high-speed wireless data transmission,the THz frequencies are now becoming a worth candidate for post-5G wireless communications.On the other hand,to bring THz communications a step closer to real scenario application,solving high data rate realtime transmission is also an important issue.This paper describes a 220-GHz solid-state dual-carrier wireless link whose maximum transmission real-time data rates are 20.8 Gbps(10.4 Gbps per channel).By aggregating two carrier signals in the THz band,the contradiction between high real-time data rate communication and low sampling rate analog-to-digital(ADC)and digital-to-analog converter(DAC)is alleviated.The transmitting and receiving front-ends consist of 220-GHz diplexers,220-GHz sub-harmonic mixers based on anti-parallel Schottky barrier diodes,G-band low-noise amplifiers(LNA),WR-4.3 band high-gain Cassegrain antennas,high data rates dual-DAC and-ADC baseband platform and other components.The low-density parity-check(LDPC)encoding is also realized to improve the bit error rate(BER)of the received signal.Modulated signals are centered at 214.4 GHz and 220.6 GHz with-11.9 dBm and-13.4 dBm output power for channel 1 and 2,respectively.This link is demonstrated to achieve 20.8-Gbps real-time data transmission using 16-QAM modulation over a distance of 1030 m.The measured signal to noise ratio(SNR)is 17.3 dB and 16.5 dB,the corresponding BER is 8.6e-7 and 3.8e-7,respectively.Furthermore,4K video transmission is also carried out which is clear and free of stutter.The successful transmission of aggregated channels in this wireless link shows the great potential of THz communication for future wireless high-rate real-time data transmission applications. 展开更多
关键词 communication systems millimeter-wave communication quadrature amplitude modulation(QAM) state circuits
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Joint synchronization estimation based on genetic algorithm for OFDM/OQAM systems 被引量:3
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作者 LIU Yongjin CHEN Xihong ZHAO Yu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期657-665,共9页
This paper investigates the problem of synchronization for offset quadrature amplitude modulation based orthogonal frequency division multiplexing(OFDM/OQAM) systems based on the genetic algorithm. In order to increas... This paper investigates the problem of synchronization for offset quadrature amplitude modulation based orthogonal frequency division multiplexing(OFDM/OQAM) systems based on the genetic algorithm. In order to increase the spectrum efficiency,an improved preamble structure without guard symbols is derived at first. On this basis, instead of deriving the log likelihood function of power spectral density, joint estimation of the symbol timing offset and carrier frequency offset based on the preamble proposed is formulated into a bivariate optimization problem. After that, an improved genetic algorithm is used to find its global optimum solution. Conclusions can be drawn from simulation results that the proposed method has advantages in the joint estimation of synchronization. 展开更多
关键词 offset quadrature amplitude modulation based orthogonal frequency division multiplexing(OFDM/OQAM) SYNCHRONIZATION joint estimation genetic algorithm
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Novel Mapping Design Criterion for BICM-ID with Square QAM Constellations 被引量:1
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作者 刘林南 费泽松 +1 位作者 赵胜辉 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2003年第4期385-389,共5页
Mapping design criteria of bit-interleaved coded modulation with iterative decoding (BICM-ID) with square 16QAM are analyzed. Three of the existing criteria are analyzed and compared with each other. Through the compa... Mapping design criteria of bit-interleaved coded modulation with iterative decoding (BICM-ID) with square 16QAM are analyzed. Three of the existing criteria are analyzed and compared with each other. Through the comparison, two main characters of the mapping design criteria are found. They are the harmonic mean of the minimum squared Euclidean distance and the average of Hamming distances with the nearest Euclidean distance. Based on these two characters, a novel mapping design criterion is proposed and a label mapping named mixed mapping is searched according to it. Simulation results show that mixed mapping performs better than the other mappings in BICM-ID system. 展开更多
关键词 bit-interleaved coded modulation with iterative decoding (BICM-ID) 16 quadrature amplitude modulation (16QAM) design criteria Hamming distance Euclidean distance
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Optimized LDPC differential-encoded 16QAM scheme for high-speed transmission systems 被引量:1
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作者 Zhanji Wu Xiang Gao Zhiyu Xiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期728-734,共7页
The 16-ary quadrature amplitude modulation (16QAM) is a high spectral efficient scheme for high-speed transmission systems. To remove the phase ambiguity in the coherent detection system, differential-encoded 16QAM ... The 16-ary quadrature amplitude modulation (16QAM) is a high spectral efficient scheme for high-speed transmission systems. To remove the phase ambiguity in the coherent detection system, differential-encoded 16QAM (DE-16QAM) is usually used, however, it will cause performance degradation about 3 dB as compared to the conventional 16QAM. To overcome the performance loss, a serial concatenated system with outer low density parity check (LDPC) codes and inner DE-16QAM is proposed. At the receiver, joint iterative differential demodulation and decoding (ID) is carried out to approach the maximum likelihood performance. Moreover, a genetic evolution algorithm based on the extrinsic information transfer chart is proposed to optimize the degree distribution of the outer LDPC codes. Both theoretical analyses and simulation results indicate that this algorithm not only compensates the performance loss, but also obtains a significant performance gain, which is up to 1 dB as compared to the conventional non-DE-16QAM. 展开更多
关键词 quadrature amplitude modulation (QAM) low density parity check (LDPC) code genetic evolution (GE) algorithm iterative demodulation and decoding (ID) extrinsic information transfer (EXIT) chart.
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ASYMPTOTIC PERFORMANCE ANALYSIS OF ARBITRARY RECTANGULAR QAM OVER FADING CHANNELS 被引量:1
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作者 Lei Xianfu Fan Pingzhi Mathiopoulos P. Takis 《Journal of Electronics(China)》 2009年第6期794-797,共4页
In this paper,the asymptotic performance of arbitrary rectangular Quadrature Amplitude Modulation (QAM) signals over fading channels is investigated. A novel unified asymptotic average Symbol Error Probability (SEP) e... In this paper,the asymptotic performance of arbitrary rectangular Quadrature Amplitude Modulation (QAM) signals over fading channels is investigated. A novel unified asymptotic average Symbol Error Probability (SEP) expression is derived in terms of diversity and coding gain. The validity and accuracy of the analytical result are verified by means of computer simulations. Furthermore,the results presented are very easy to be extended to the systems with multi-channel diversity receivers. 展开更多
关键词 quadrature amplitude modulation (QAM) Fading channel Symbol Error Probability(SEP)
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Symbol Detection Based on Temporal Convolutional Network in Optical Communications
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作者 Yingzhe Luo Jianhao Hu 《China Communications》 SCIE CSCD 2022年第1期284-292,共9页
Deep learning(DL)is one of the fastest developing areas in artificial intelligence,it has been recently gained studies and application in computer vision,automatic driving,automatic speech recognition,and communicatio... Deep learning(DL)is one of the fastest developing areas in artificial intelligence,it has been recently gained studies and application in computer vision,automatic driving,automatic speech recognition,and communication.This paper uses the DL method to design a symbol detection algorithm in receiver for optical communication systems.The proposed DL based method is implemented by a non-causal temporal convolutional network(ncTCN),which is a convolutional neural network and appropriate for sequence processing.Meanwhile,we adopt three methods to realize the training process for multiple signal-to-noise ratios of the AWGN channel.Furthermore,we apply two nonlinear activation functions for the noise robustness to the proposed ncTCN.Without losing generality,we apply the ncTCN-based receiver to the 16-ary quadrature amplitude modulation optical communication system in the simulation experiment.According to the experiment results,the proposed method can obtain some bit error rate performance gain compared to some conventional receivers. 展开更多
关键词 deep learning optical communicaitons quadrature amplitude modulation symbol detection
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