Error performance of multi-branch dual-hop PF cooperative systems by Guangqiu LI, Jiayun DONG, Tao JIANG

“…Design of multi-branch dual-hop phase-only forward(PF)cooperative systems with continuous phase frequency shift keying(CPFSK)modulation needs to determine the number of branch and modulation index.The usual solution of determining the above parameters is the time-consuming and inefficient computer simulation.An efficient solution of determining these parameters is theoretical analysis method.Semi-analytical expressions for the average bit error rate(ABER)of multi-branch dual-hop PF cooperative systems in conjunction with discrimination detection CPFSK over time-selective Rayleigh fading channels was presented.Two cases with and without antenna selection at the relays and maximum-ratio combining(MRC)receive diversity at the destination were considered.The simulation results show that numerical calculation results and simulation results for the ABERs of PF，discrimination detection,CPFSK cooperative systems are consistent and show that the above ABER theory results of CPFSK cooperative systems can be used to design PF cooperative systems.…”
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Research on Design of Extending Orthogonal Space-Time Block Code by Adan Ding, Fei Long, Zhuoyue Li

“…The simulation results show that the bit error rate of the system is reduced and the signal-to-noise ratio gain of the system is improved by the two kinds of improved scheme, and compared with the scheme which is combined with antenna selection technology, the performance of the second scheme combined with adaptive power allocation is superior.…”
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Influence of thunderstorm cloud on the performance of satellite-to-ground quantum link and parameters simulation by Min NIE, Li SHI, Guang YANG, Chang-xing PEI

“…In order to investigate the effect of thunderstorm cloud on the performance of satellite-to-ground quantum link,according to the extinction cross section and the number concentration distribution function of the charged particle in the thunderstorm cloud,the relationships among the particle concentration,charge density and link attenuation of charged particles in atmosphere were established.The relationship between the atmospheric concentration of charged particles,the charge density on the average channel capacity,channel fidelity,channel survival function and bit error rate of quantum key distribution system were put out.The simulation results show that the thunderstorm cloud has a significant effect on the performance of the satellite-to-ground quantum link.So in order to improve the reliability of satellite-ground quantum communication,the system parameters should be adjusted according to the forecast of the thunderstorm cloud.…”
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Secure D2D underlaying cellular communication based on artificial noise assisted by Xiao-lei KANG, Xin-sheng JI, Kai-zhi HUANG

“…A secure communication scheme based on artificial noise assisted from base station(BS)was proposed to improve the system secrecy rate of the D2D underlaying cellular.Firstly,the system secrecy rate was modeled.Then the BS with multi-antennas added artificial noise(AN)in cellular user’s signal as well as designed beam vectors of the desired signal and artificial noise to maximize system secrecy rate.In the end,a joint optimization scheme based on the fairness constraint was introduced to optimize beam vectors of the desired signal,the power allocation for BS’s information signal and AN and the D2D power control.Simulation results show that the system ergodic secrecy rate can be improved 2.7 bit·s⁻¹·Hz⁻¹more than the schemes based on SVD and zero-forcing at most.…”
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Underwater acoustic communications based on differential chaos shift keying by Hongying DAI, Menglei CHEN, Weikai XU

“…As the most stringent and complicated channel,underwater acoustic (UWA) channels are featured by high multipath interference,time-frequency doubly spread,high noise,and narrow bandwidth.Due to time varying of underwater acoustic,it is difficult to trance and estimate channel state information (CSI).The underwater acoustic communication techniques based on orthogonal frequency division multiplex (OFDM) and spread spectrum were reviewed.Then,the characteristic of differential chaos shift keying (DCSK) was analyzed,and two multicarrier differential chaos shift keying modulations were proposed.Finally,over time-frequency doubly spread channel and underwater acoustic channel,the bit errors rate (BER) performances for two proposed schemes were presented and analyzed.Numerical results show that the proposed schemes own good robustness over underwater acoustic channels.…”
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OFDM transmission scheme with subcarrier supply index modulation by Yi GUO, Yiqing WANG, Yuanyuan FAN, Gang LIU

“…To address the drawback that subcarrier activation pattern (SAP) of the orthogonal frequency division multiplexing with index modulation (OFDM-IM) cannot match the binary numbers which affects the system performance, the orthogonal frequency division multiplexing with subcarrier supply index modulation (OFDM-SSIM) transmission scheme was proposed.The index utilization of the system was improved and the spectral efficiency (SE) of the system was enhanced by adding the supply index.Also, as the subcarrier activation pattern of the proposed scheme match the binary numbers, low complexity log-likelihood ratio (LLR) detection was made easy to adopt and bit error rate (BER) performance was maintained good.Theoretical analysis and simulation results show that the proposed scheme effectively improves the SE and BER performance over classical OFDM-IM scheme in additive white Gaussian noise (AWGN) channels and Rayleigh fading channels.…”
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Decision-aided-based multiple blind PN code estimation algorithm of asynchronous CDMA signal by Zhaoyang QIU, Tianyun LI, Xiangming CHEN

“…Aiming at the problem of blind estimation of multi-user pseudo-code of multi-path asynchronous code division multiple access (CDMA) signal,using the finite element (FA) characteristic of transmitted symbol,a decision aid (DA) method based on maximum likelihood was proposed.A two-step iterative estimation structure for PN code,transmitted bit and channel was designed to realize the estimation of multiple user code in asynchronous CDMA system with superior performance.Moreover,the Cramer-Rao bound (CRB) of PN code estimation in asynchronous CDMA signal was derived to evaluate the performance of proposed method.Simulation indicates significant improvement in performance which is close to the theory bound of the proposed method compared to commonly-used iterative least square with projection (ILSP) method.The method can also achieve superior estimation when the user number increases.…”
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An Analytical Multimodulus Algorithm for Blind Demodulation in a Time-Varying MIMO Channel Context by Steredenn Daumont, Daniel Le Guennec

“…The adaptive-AMMA and adaptive-ASCMA achieve a lower residual intersymbol interference and bit error rate than those of the adaptive-ACMA and MMA.…”
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Sungai Batu Archaeological Complex (SBAC) in Kedah, Malaysia, as a sustainable heritage tourism product by Mohd Hasfarisham Abd Halim, Shyeh Sahibul Karamah Masnan, Mokhtar Saidin

“…To support heritage tourism, the data collected through field studies were processed into a 3-dimensional form via CorelDraw X7 (64-bit) and 3ds Max software. The Living Culture Gallery at the SBAC develops heritage tourism by applying digital technology such as VR, AR, hologram fans, and QR codes. …”
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One-way hash function construction based on Chen-type hyper-chaotic system and key-stream by REN Hai-peng, ZHUANG Yuan

“…Then, the cipher block chaining mode was used to generate the 128bit hash value for the plain-text with arbitrary length. …”
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Real-Time Multichannel Imaging Framework for Endoscopy, Catheters, and Fixed Geometry Intraoperative Systems by Rahul A. Sheth, Rabi Upadhyay, Ralph Weissleder, Umar Mahmood

“…Data are processed and saved as 12-bit files, matching the standards of clinical imaging. …”
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Non-holomorphic modular A4 symmetric scotogenic model by Takaaki Nomura, Hiroshi Okada, Oleg Popov

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Loop interference suppression based on space projection in full-duplex MIMO relays by Ji-song YANG, Hao LIU, Chen SUN

“…The system model including base station,full duplex MIMO relay and user station was established,and then obtained the loop interference matrix.While the case that loop interference signal's maximum multipath delay was greater than the symbol period was taken into account,signal space projection filters were designed to suppress the loop interference according to the space expanded by loop feedback interference matrix.Confronted the loop interference ma-trix full rank or not,filter design was based on subspace projection or null space projection algorithm.It was discussed that the projection algorithm how to influence the residual interference signal and the bit error rate of the relay station.Theoretical analysis and simulation results prove that the proposed space projection algorithm has ideal effect on sup-pressing loop interference.…”
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Algorithm based on randomly assigning filters to reduce PAPR in GFDM system by Miao ZHANG, Xianzhong XIE, Lei WU, Weijia LEI

“…As an alternative of the fifth generation mobile communication system waveforms,generalized frequency division multiplexing(GFDM)which has more advantages over OFDM has been trusted into the limelight.Nevertheless,GFDM still suffers from a high peak to average power ratio(PAPR).Considering that different filters have their own phase-frequency characteristics,a new algorithm based on randomly assigning filters to reduce PAPR in GFDM(RAF-GFDM)was proposed.According to the feature of GFDM system that the filter structure could be selected flexibly,different filters were assigned to subcarriers randomly to adjust the phase congruency due to signals superimposition.Additionally,this method can suppress PAPR effectively without causing signal distortion.Theoretical analysis and simulation results demonstrate that the proposed algorithm does not bring additional calculation costs while reducing PAPR and almost has no effect on the bit error rate(BER),and it may provide a higher application value.…”
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Improved Maximum Likelihood S-FSK Receiver for PLC Modem in AMR by Mohamed Chaker Bali, Chiheb Rebai

“…Because of the hostile communication environments of power line channel, a new design approach is carried out for an S-FSK demodulator capable of providing lower bit error rate (BER) than standard specifications. …”
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Joint vibrotactile coding for machine recognition and human perception by Ying FANG, Yiwen XU, Tiesong ZHAO

“…In order to accurately transmit the content meaning of vibrotactile signals and achieve intelligent recognition and signal reconstruction, a joint vibrotactile coding scheme for machine recognition and human perception was proposed.At the encoding end, the original three-dimensional vibrotactile signals were converted into one-dimensional signals.Then the semantic information of the signals was extracted using a short-time Fourier transform before being effectively compressed and transmitted.At the decoding end, a fully convolutional neural network was used to intelligently recognize based on the semantic information.The difference between the original signals and the reconstructed signals based on semantic information was used as compensation for the semantic information, and the quality of the reconstructed signals was gradually improved to meet human perceptual needs.The experimental results show that the proposed scheme achieve tactile recognition with semantic information at a lower bit rate while improving the compression efficiency of tactile data, thus satisfying human perceptual needs.…”
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Pilot-assisted non-cyclic prefixed SFBC-OFDM by REN Shu-bo, SHANG Yong, GUO Jun-qi, XIANG Hai-ge

“…Simulation results show that the proposed system based on the recursive algorithm achieves lower bit error rate （BER） and higher information data transmission rate than the traditional cyclic prefixed STBC-OFDM system with least square （LS） or iterative LS channel estimation algorithm.…”
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Simulation of transmission characteristics of oceanic wireless optical communication systems based on orbital angular momentum multiplexing with space-time coding by Xiaoli YIN, Tong ZHENG, Zhiwen SUN, Zhaoyuan ZHANG

“…In order to mitigate the crosstalk caused by oceanic turbulence in the underwater wireless orbital angular momentum multiplexing optical communication system, the application of space-time coding technology in the system was studied.Based on Rytov approximation, the covariance method and interpolation method were used to simulate correlated random phase screens and then the influence of time-varying oceanic turbulence channel on orbital angular momentum signal was studied.The transmission characteristics of orbital angular momentum multiplexing optical communication system with space-time coding was analyzed by simulation.The phase structure function of the time-varying phase screens and the detection probability distribution of the beam carrying the orbital angular momentum through the time-varying simulation channel were in line with theoretical expectations.The simulation results show that the space-time coding technology can effectively mitigate the influence of ocean turbulence on the system bit error rate.…”
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Etude d’un phénomène de discrimination esthétique : la « naquez » au Mexique by Philippe Schaffhauser

“…Finally, if every Mexican is « a little bit naco », and each considers his neighbor or brother-in-law to be more so, it is worth pointing out that this matter of aesthetic tastes is a universal datum.…”
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Novel Chaos Secure Communication System Based on Walsh Code by Gang Zhang, Niting Cui, Tianqi Zhang

“…A multiuser communication scheme which is a hybrid of Walsh code with DCSK and CDSK is proposed to improve low data transmission rate of Differential Chaos Shift Keying (DCSK), poor bit error ratio (BER) performance of Correlation Delay Shift Keying (CDSK), and disadvantage of orthogonality in traditional multiuser DCSK. …”
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