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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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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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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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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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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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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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A 16-QAM 45-Gbps 7-m Wireless Link Using InP HEMT LNA and GaAs SBD Mixers at 220-GHz-Band
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作者 Yukun Li Yong Zhang +3 位作者 Chengkai Wu Jianhan Cui Huali Zhu Bo Yan 《China Communications》 SCIE CSCD 2021年第5期255-262,共8页
This paper presents a 220-GHz-band 7-m wireless link with a 45-Gbps transmission data rate by using 16 quadrature amplitude modulation(16-QAM).Super-heterodyne transceiver modules are developed for transmission and re... This paper presents a 220-GHz-band 7-m wireless link with a 45-Gbps transmission data rate by using 16 quadrature amplitude modulation(16-QAM).Super-heterodyne transceiver modules are developed for transmission and reception of the modulated signals,which consist of a Schottky barrier diodes(SBD)based sub-harmonic mixer(SHM),an InP HEMT low noise amplifier(LNA),a waveguide band-pass filter(BPF),and a 108-GHz local oscillator(LO)multiplier chain.The transmitter features a peak transmit power of 1.41 dBm,and the IF frequency varies from 5 GHz to 20 GHz.Besides,the receiver features a conversion gain of 9.3 dB in average and a noise temperature of 3052.8 K.The measured results indicate that the transceiver modules enable data transmission of a 45-Gbps 16-QAM signal with Signal-Noise-Ratio(SNR)from 11.59 dB to 15.36 dB in a 7-m line-of-sight channel. 展开更多
关键词 wireless link 16 quadrature amplitude modulation(16-QAM) super-heterodyne transceiver modules sub-harmonic mixer(SHM)
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Adaptive Turbo Equalization for Probabilistic Constellation Shaped Underwater Acoustic Communications
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作者 Xisheng Wu Yanbo Wu +1 位作者 Min Zhu Dong Li 《Journal of Beijing Institute of Technology》 EI CAS 2021年第3期280-289,共10页
To increase the spectral efficiency of the underwater acoustic(UWA)communication system,the high order quadrature amplitude modulations(QAM)are deployed.Recently,the prob-abilistic constellation shaping(PCS)has been a... To increase the spectral efficiency of the underwater acoustic(UWA)communication system,the high order quadrature amplitude modulations(QAM)are deployed.Recently,the prob-abilistic constellation shaping(PCS)has been a novel technology to improve the spectral efficiency.The PCS with high-order QAM is introduced into the UWA communication system.A turbo equal-ization scheme with PCS was proposed to cancel the severe inter-symbol interference(ISI).The non-zero a priori information is available for the equalizer and decoder before turbo iteration.A pri-ori hard decision approach is proposed to improve the detection performance and the equalizer con-vergence speed.At the initial turbo iteration,the relation between the a priori information and the probability of the amplitude of 16QAM symbols in one dimension is given.The simulation results verified the efficiency of the proposed method,and compared to the uniform distribution(UD),the PCS-16QAM had a significant improvement of the bit error rate(BER)performance with PCS-ad-aptive turbo equalization(PCS-ATEQ).The UWA communication experiments further verified the performance superiority of the proposed method. 展开更多
关键词 high order quadrature amplitude modulation probabilistic constellation shaping UWA multipath channel turbo equalization
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