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Reflection-transmission Transition of Bright-Bright Solitons Collision in Two Species Condensates with Repulsive Interspecies Interactions

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Communications in Theoretical Physics 2012年第9期58卷 381-386页

作者：何章明王登龙丁建文颜晓红 Department of Physics Xiangtan University College of Electronic Science Engineering Nanjing University of Post&Telecommunication

Considering repulsive interspecies interactions,we study the dynamical properties of bright-bright solitons in two species Bose-Einstein condensates by using a variational approach combined with numerical *** is shown that the interactions between bright-bright solitons vary from repulsive to attractive interactions with the increasing their separating distances,and at equilibrium position the bright-bright solitons are ***,a transition from reflection-to transmission-collision is firstly observed,different from previous results of only reflection collision appearing *** results will be helpful for the experimental manipulating such solitons.

关键词： bright-bright solitons two species Bose-Einstein condensates collisions

System Integration of Terrestrial Mobile Communication and Satellite Communication——The Trends, Challenges and Key Technologies in B5G and 6G

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China Communications 2020年第12期17卷 156-171页

作者： Shanzhi Chen Shaohui Sun Shaoli Kang State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunication TechnologyBeijing 100191China

Mobile communication standards have been developed into a new era of B5G and *** recent years,low earth orbit(LEO)satellites and space Internet have become hot *** integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in *** paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within *** on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.

关键词： satellite communication terrestrial mobile communication system integration B5G 6G space internet

Analysis of reflected signal of quad rotor UAV based on model fitting in mobile communication system

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Journal of Systems Engineering and Electronics 2022年第1期33卷 97-104页

作者： LI Xiaohui FANG Cong FAN Tao School of telecommunication Engineering Xidian UniversityXi’an 710071China Guangzhou Institute of Technology Xidian UniversityGuangzhou 510555China

In view of the many scenes of unmanned aerial vehicle(UAV)detection,a third-party signal source is used to design a receiver to monitor the *** is of great significance to understand the reflection of the signal illuminating the *** the communication base station(BS)signal as the third-party signal source,and considering the complete transmission link,reflection changes and loss fading of the communication signal,this study conducts model fitting for irregular UAV targets,simplifying complex targets into a combination of simple ***,the influence of the dielectric constant of the target surface and the signal irradiation angle on the signal reflection is *** analysis shows that the simulation results of this model fitting method are consistent with the results of other literature,which provides theoretical support for the detection of low and slow small targets such as UAVs.

关键词： mobile communication signal quad rotor unmanned aerial vehicle(UAV) signal reflection model fitting

Research on Threshold Adjustment Algorithm in Adaptive Modulation and Coding

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The Journal of China Universities of Posts and telecommunications 2006年第2期13卷 15-19页

作者： FAN Chen CHEN Mei-ya SU Li-jun YANG Da-cheng School of telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

Adaptive Modulation and Coding （AMC） has gained a lot of attentions in the research of High Speed Downlink Packet Access （HSDPA）. The idea is to adapt the transmission to the fast changing channel conditions by the use of different Modulation and Coding Schemes （MCS）. This paper presents an adaptive AMC algorithm and introduces a theoretical analysis model in order to to investigate its throughput and Frame Error Rate （FER）. Subject to the given FER target, our numerical and link level simulation results both show that our algorithm outperforms other existing adaptive algorithms.

关键词： adaptive modulation and coding threshold adjust markov model HSDPA

Synthesis and photoluminescence properties of Nd_2O_3 nanoparticles modified by sodium bis(2-ethylhexyl) sulfosuccinate

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Chinese Physics B 2008年第12期17卷 4669-4672页

作者：任建华赵同刚刘建华孔娟贺加欣郭林 School of Electronic Engineering Beijing University of Posts and Telecommunication School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics

This paper reports that Nd2O3 nanoparticles modified by AOT（sodium bis（2-ethylhexyl） sulfosuccinate） were prepared using microemulsion method in the system of water and propanol/AOT/toluene. transmission electron microscopy shows that the Nd2O3 nanoparticles take the shape of sphere with 18 nm and 31 nm with different preparation. The organic sol of Nd2O3 nanoparticles is very stable at room temperature. X-ray diffraction results show that the product has hexagonal phase structure. Two ultraviolet emission band at 344 nm and 361 nm corresponding to the transition of ^4 D3/2→4 I9/2 and 2P3/2→^4I 11/2 or ^4D 3/2→ ^4 I 13/2 were observed.

关键词： Nd2O3 nanocrystals photoluminescence spectrum surface modification

Switchable instantaneous frequency measurement by optical power monitoring based on DP-QPSK modulator

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Chinese Physics B 2022年第4期31卷 336-347页

作者： Yu-Lin Zhu Bei-Lei Wu Jing Li Mu-Guang Wang Shi-Ying Xiao Feng-Ping Yan Institute of Lightwave Technology Key Laboratory of All Optical Network and Advanced Telecommunication of EMCBeijing Jiaotong UniversityBeijing 100044China

We propose and analyze an instantaneous frequency measurement system by using optical power monitoring technique with improved *** primary component adopted in the proposal is a dual-polarization quadrature phase shift keying(DP-QPSK) modulator which is used to modulate the microwave signal that has a designed time delay and phase *** generated optical signal is sent to polarization beam splitter(PBS) in DP-QPSK *** to the complementary transmission nature of polarization interference introduced by PBS,the frequency information is converted into the optical power and the relationship between the amplitude comparison function(ACF) and microwave frequency to be measured is ***,the frequency of the microwave signal can be easily measured through monitoring the optical powers of the two output ports of the ***,by adjusting the direct current(DC) biases of the DP-QPSK modulator instead of changing the electrical delay,the measurement range and resolution can be *** this paper,the basic principle of the instantaneous frequency measurement system is derived in detail,and simulation has been performed to investigate the resolution,the measurement range,and the influence of imperfection *** proposed scheme is wavelength-independent and its measurement range is switchable,which can avoid the laser wavelength drifting problem and thus greatly increasing the system flexibility.

关键词： microwave photonics DP-QPSK modulator instantaneous frequency measurement

Uplink NOMA signal transmission with convolutional neural networks approach

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Journal of Systems Engineering and Electronics 2020年第5期31卷 890-898页

作者： LIN Chuan CHANG Qing LI Xianxu School of Electronic and Information Engineering Beihang UniversityBeijing 100191China State Grid Information and telecommunication Branch Beijing 100761China

Non-orthogonal multiple access(NOMA), featuring high spectrum efficiency, massive connectivity and low latency, holds immense potential to be a novel multi-access technique in fifth-generation(5G) communication. Successive interference cancellation(SIC) is proved to be an effective method to detect the NOMA signal by ordering the power of received signals and then decoding them. However, the error accumulation effect referred to as error propagation is an inevitable problem. In this paper,we propose a convolutional neural networks(CNNs) approach to restore the desired signal impaired by the multiple input multiple output(MIMO) channel. Especially in the uplink NOMA scenario,the proposed method can decode multiple users' information in a cluster instantaneously without any traditional communication signal processing steps. Simulation experiments are conducted in the Rayleigh channel and the results demonstrate that the error performance of the proposed learning system outperforms that of the classic SIC detection. Consequently, deep learning has disruptive potential to replace the conventional signal detection method.

关键词： non-orthogonal multiple access(NOMA) deep learning(DL) convolutional neural networks(CNNs) signal detection

ISSAMAC: a High Speed MAC Protocol for B3G Systems

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The Journal of China Universities of Posts and telecommunications 2006年第1期13卷 53-59页

作者： GU Xue-lin TIAN Hui YANG Ning ZHANG Ping ZHANG Ping College of telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

Based on a discussion of the requirements for the multiple acess control protocol of beyond thlrd-generation mobile systems, we in this paper articulate the needs of the new multiple acess control protocol with support of high-speed transmission and guaranteed quality of service, for voice, video and audio. In light of these, we present the design of a new multiple acess control protocol, called intelligent slot-subcarriered assignment multiple acess control protocol, to support multiple service categories and to yield high spectral efficiency. Our simulation results verify that intelligent slot-subcarriered assignment multiple acess control protocol can not only provide low delays for the real-time traffic by using bandwidth reservation and effectual scheduling, but also make full use of the limited bandwidth by using a dynamic sub-carrier assignment algorithm.

关键词： B3G multiple acess control QoS OFDMA MIMO

Concurrent streaming over heterogeneous wireless networks:technology and realization

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The Journal of China Universities of Posts and telecommunications 2018年第5期25卷 49-59,66页

作者： Zhu Xiaorong Dong Tiancai Wang Yong College of telecommunication and Information Engineering Nanjing University of Posts and Telecommunications School of Electrical Engineering Nanjing Institute of Industry Technology

Some emerging services such as augmented/virtual reality need high data rates. Whereas,the existing 2 nd generation（ 2 G）,the 3 rd generation（ 3 G） and the 4 th generation（ 4 G） networks cannot provide such high transmission rates. To meet these requirements,the technology and the realization of a‘virtual super terminal＇that can perform the concurrent streaming of video via the cooperation of multiple heterogeneous terminals are introduced. The proposed algorithm uses concurrent streaming scheduling algorithm,buffer overhead and packet delivery method,and packet loss prevention and recovery method to improve the performances of the *** measurements show that compared with the scheme without cooperative transmission the proposed design can significantly increase system throughput and decrease packet delay.

关键词： heterogeneous networks virtual terminal muhi-termlnal cooperation video streaming