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Digital Signal Processing for High-Speed THz Communications

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Chinese Journal of Electronics 2022年第3期31卷 534-546页

作者： yu jianjun WEI Yi School of Information Science and Technology Fudan University

The use of advanced digital signal processing(DSP) technology in the high-speed terahertz(THz) communication can effectively compensate the linear and nonlinear effects of the system and further improve the transmission performance of the system. This paper introduces the principle and application of advanced DSP algorithms such as probability shaping(PS)technology, Volterra series nonlinear compensation algorithm, Kramers-Kronig receiver, look-up table(LUT)pre-distortion compensation technology, pre-equalization and decision-directed least-mean-square equalization algorithm. Combined with DSP algorithms such as PS and LUT pre-distortion, using photon-assisted technology to successfully realize the wireless transmission of vector THz signals higher than 1 Tbit/s on the sub-THz band(D-band) 4 × 4 multiple input multiple output system.

关键词： Volterra series nonlinear compensation algorithm decision-directed least-mean-square equalization algorithm high-speed THz communications equalisers wireless channels photon-assisted technology least mean squares methods Kramers-Kronig relations look-up table pre-distortion compensation technology multiple input multiple output system advanced DSP algorithms radio receivers Volterra series high-speed terahertz communication MIMO communication probability Kramers-Kronig receiver transmission performance nonlinear effects signal processing advanced digital signal processing

Novel schemes to generate multi-level modulation formats for ultra-capacity coherent detection transmission systems

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Chinese Optics Letters 2010年第9期8卷 823-830页

作者： jianjun yu Xiang Zhou ZTE USA Inc. Iselin NJ 08830 USA and also with ZTE Inc. Beijing 100876 China AT&T Labs-Research Middletown NJ 07748 USA

We summarize several novel schemes to generate multi-level modulation formats for high capacity transmission system with high spectral efficiency. We show that multi-level 8QAM, 16QAM, 32QAM, and 64QAM （QAM： quatlrature amplitude modulation） optical signals can be generated by commercial optical and electrical devices. Employing these multilevel modulation formats, we have realized PDM-8QAM （PDM： polarization division multiplexing） 32 Tb/s and PDM-36QAM 64-Tb/s signals transmission over 580-and 320-km fibers, respectively.

关键词： Spectrum analyzers

Combining long-term and short-term user interest for personalized hashtag recommendation

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Frontiers of Computer Science 2015年第4期9卷 608-622页

作者： jianjun yu Tongyu ZHU Computer Network Information Center Chinese Academy of Sciences Beijing 100190 China State Key Lab of Software Development Environment B eihang University Beijing 100190 China

Hashtags, terms prefixed by a hash-symbol #, are widely used and inserted anywhere within short messages （tweets） on micro-blogging systems as they present rich sen- timent information on topics that people are interested in. In this paper, we focus on the problem of hashtag recommenda- tion considering their personalized and temporal aspects. As far as we know, this is the first work addressing this issue spe- cially to recommend personalized hashtags combining long- term and short-term user interest. We introduce three features to capture personal and temporal user interest： 1） hashtag textual information; 2） user behavior; and 3） time. We of- fer two recommendation models for comparison： a linear- combined model, and an enhanced session-based temporal graph （STG） model, Topic-STG, considering the features to learn user preferences and subsequently recommend person- alized hashtags. Experiments on two real tweet datasets illus- trate the effectiveness of the proposed models and algorithms.

关键词： recommendation hashtag time-sensitive userinterest

104-m wireless transmission of 4096-QAM for mobile backhaul based on delta-sigma modulation in 145 GHz

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Science China(Technological Sciences) 2023年第7期66卷 2155-2157页

作者： WANG MingXu yu jianjun Department of Communication Science and Engineering Key Laboratory for Information Science of Electromagnetic Waves(MoE)Fudan UniversityShanghai 200433China

This year,the global data traffic will grow up to 4.8 zettabytes annually,which is 11 times more than all data traffic generated in 2012 (437 exabytes)[1].The huge data traffic is mainly caused by video-intensive services,such as Internetof-Things (IoT),4 K/8 K *** high capacity and bandwidth requirement from the transport network to the core is a major challenge in the 5G ***,the millimeter wave (MMW) with a much wider bandwidth is a very important backhaul solution [2,3].

关键词： millimeter IoT video

Recent Progress in High-speed and High Spectral Efficiency Optical Transmission Technology

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China Communications 2010年第3期7卷 24-34页

作者： Zhou Xiang yu jianjun AT＆T Labs-Research Middletown NJ 07748 USA ZTE USA Inc.NJ USA ZTE Inc. Shenzhen 518057 Guangdong Province P. R. China

Increasing the spectral efficiency and per channel data rate have historically been shown to be the most cost-effective method to meet the need of ever growing capacity demand in the core network. In this paper we review recent progress in high-speed and high-spectral-efficient optical transmission technology. We discuss spectrally efficient modulation and detection technologies that have been experimentally explored for future 100-Gb/s and above optical transmission system. Emerging methods aiming at extending system reach for noise and nonlinearity-stressed high spectral efficiency optical transmission systems have also been reviewed. We show that spectrallyefficient multilevel coding coupled with polarization multiplexing and digital coherent detection has the potential to enable 400Gb/s per channel WDM system operating with existing 50GHzspaced WDM infrastructure at a spectral efficiency of 8b/s/Hz.

关键词： optical modulation format coherent detection fiber and DSP

Demonstration of 5.12-Tbps THz-over-fiber transmission in 80 channel WDM system

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Science China(Technological Sciences) 2023年第5期66卷 1480-1482页

作者： ZHAO Li LONG Jianyu DING JunJie yu jianjun Department of Communication Science and Engineering Fudan UniversityShanghai 200433China

The arrival of 5G and the incoming 6G era demand ultralarge-capacity and long-distance transmission for wired and wireless *** adequate bandwidth,the terahertz(THz)-wave(0.3 THz–10 THz)is very promising and has the ability to carry ultra-high-speed signals[1–7].However,there has been little research on THz-over-fiber technology until ***,it is extremely competitive and challenging to achieve the potential THz-over-fiber communication for the 6G technology in the near future.

关键词： fiber WDM carry

ORDER DECISION MAKING BASED ON DIFFERENT STATEMENT STRATEGIES UNDER STOCHASTIC MARKET DEMAND

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Journal of Systems Science and Systems Engineering 2013年第2期22卷 171-190页

作者： Jiangtao WANG Liwen WANG Fei YE Xuejun XU jianjun yu School of Business Administration South China University of Technology Economics and Management School of Beihang University

Based on the stochastic market demand, this paper considers the order decision-making strategies of the supply chain by introducing statement strategies. Consequently, the time-variant variance in the demands of the market is incorporated into the model. The retailer simultaneously determines the purchase time （i.e., lead time） and order quantity, and the manufacturer determines the statement strategy and the reserved profit rate. The results show that the no overtime statement strategy can induce the retailer to place more orders in advance by limiting the available order quantity within the available time. Finally, we also adopt numerical examples to support the conclusion of this paper.

关键词： Stochastic demand cost-oriented statement strategy lead time

Recent progress on high-speed optical transmission

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Digital Communications and Networks 2016年第2期2卷 65-76页

作者： jianjun yu Junwen Zhang Key Laboratory for Information Science of Electroma1netic Waves (EOM). Fudan University. Shanghai 200433. China ZTE (TX) Inc. Morristown NJ 07920 USA

The recently reported high spectral efficiency （SE） and high-baud-rate szgnal transmission are all Daseo on digital coherent optical communications and digital signal processing （DSP）. DSP simplifies the re- ception of advanced modulation formats and also enables the major electrical and optical impairments to be processed and compensated in the digital domain, at the transmitter or receiver side. In this paper, we summarize the research progress on high-speed signal generation and detection and also show the progress on DSP for high-speed signal detection. We also report the latest progress on multi-core and multi-mode multiplexing.

关键词： Coherent optical detectionModulation formatCapacityOptical fiber communication

Demonstration of record-high 352-Gbps terahertz wired transmission over hollow-core fiber at 325 GHz

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Science China(Information Sciences) 2022年第2期65卷 241-242页

作者： Min ZHU Jiao ZHANG jianjun yu Xiaohu YOU National Mobile Communications Research Laboratory Southeast University School of Information Science and Technology Fudan University

Terahertz (THz) waves,extending from 0.1 to 10 THz,are attracting extensive attention in the interdisciplinary fields of electronics and *** THz band offers a larger available bandwidth,which can meet the Tbps transmission capacity for 6G wireless ***,it could enable high-resolution sensing and imaging to implement Internet of Things (Io T) for trillion communicating devices,owing to the short wavelength compared to the microwave system[1].

关键词： THz communication THz hollow-core fiber optical-THz-optical communication advanced multi-dimension multiplexing techniques THz in-depth coverage