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Efficient electronic entanglement concentration assisted by single mobile electrons

Chinese Physics B 2013年第11期22卷 178-182页

作者：盛宇波周澜 Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education College of Mathematics & Physics Nanjing University of Posts and Telecommunications

We present an efficient entanglement concentration protocol （ECP） for mobile electrons with charge detection. This protocol is quite different from other ECPs for one can obtain a maximally entangled pair from a pair of less-entangled state and a single mobile electron with a certain probability. With the help of charge detection, it can be repeated to reach a higher success probability. It also does not need to know the coefficient of the original less-entangled states. All these advantages may make this protocol useful in current distributed quantum information processing.

关键词： quantum communication entanglement entanglement concentration

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Survival prediction in diffuse large B-cell lymphoma patients: multimodal PET/CT deep features radiomic model utilizing automated machine learning

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JOURNAL OF CANCER RESEARCH AND CLINICAL ONCOLOGY 2024年第10期150卷 452页

作者： Chen, Jianxin Lin, Fengyi Dai, Zhaoyan Chen, Yu Fan, Yawen Li, Ang Zhao, Chenyu Nanjing Univ Posts & Telecommun Key Lab Broadband Wireless Commun & Sensor Network Minist Educ Nanjing Peoples R China

PurposeWe sought to develop an effective combined model for predicting the survival of patients with diffuse large B-cell lymphoma (DLBCL) based on the multimodal PET-CT deep features radiomics signature (DFR-signature).Methods369 DLBCL patients from two medical centers were included in this study. Their PET and CT images were fused to construct the multimodal PET-CT images using a deep learning fusion network. Then the deep features were extracted from those fused PET-CT images, and the DFR-signature was constructed through an Automated machine learning (AutoML) model. Combined with clinical indexes from the Cox regression analysis, we constructed a combined model to predict the progression-free survival (PFS) and the overall survival (OS) of patients. In addition, the combined model was evaluated in the concordance index (C-index) and the time-dependent area under the ROC curve (tdAUC).ResultsA total of 1000 deep features were extracted to build a DFR-signature. Besides the DFR-signature, the combined model integrating metabolic and clinical factors performed best in terms of PFS and OS. For PFS, the C-indices are 0.784 and 0.739 in the training cohort and internal validation cohort, respectively. For OS, the C-indices are 0.831 and 0.782 in the training cohort and internal validation ***-signature constructed from multimodal images improved the classification accuracy of prognosis for DLBCL patients. Moreover, the constructed DFR-signature combined with NCCN-IPI exhibited excellent potential for risk stratification of DLBCL patients.

关键词： Multimodal fusion Deep features Automated machine learning Radiomics signature Diffuse large B-cell lymphoma

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Hybrid Indoor Localization Method Based on Signal Subspace Fingerprint Database 17

Hybrid Indoor Localization Method Based on Signal Subspace F...

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2017 17th IEEE International Conference on communication Technology (ICCT 2017)

作者： Weigang Wang Wenrui Wang Kexue Sun School of Electronic Science and Engineering Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and sensor network technology ministry of education

ISBN: (纸本)9781509039456;9781509039449

To solve the localization problem of multipath propagation in complex indoor circumstance, a localization method of signal subspace matching based on fingerprint database is proposed by using small antenna array in the indoor environment. Compared to the RSSI, the signal subspace fingerprint can obtain better effect by utilizing more space information. The received signal from each array is firstly processed with self-correlation and it's eigenvalue decomposed to create the signal subspace fingerprint. Location is then determined by the smallest angle between the received signal subspace and the fingerprint database. Simulation results show that the proposed algorithm has made a great improvement in localization accuracy.

关键词： indoor localization fingerprint database subspace matching hybrid localization

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Transmit correlation effect on SIC-ZF receiver for V-BLAST system

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Science in China(Series F) 2009年第12期52卷 2290-2295页

作者： GUO HaiYou ZHOU ZhiGang HU HongLin Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China Shanghai Research Center for Wireless Communications Shanghai 200335 China

It has been shown that transmit correlation causes a signal-to-noise ratio （SNR） loss in the zero forcing （ZF） receiver for V-BLAST （Vertical Bell labs LAyered Space-Time） system. In this paper, we investigate the transmit correlation effect on the ZF receiver with successive interference cancellation （SIC）. We show that such an unfavorable condition leads to twofold effects on the performance degradation. In addition to the immediate SNR loss, the transmit correlation can increase the propagation factor to spread decision error significantly. These two effects are evaluated analytically. We derive the probability density function （pdf） of the effective SNR at each decoded stream, and hence accurately quantify the SNR loss. We also calculate the decision error propagation factor in terms of its second moment. In particular, we show that transmit correlation can cause a stable component of error propagation which does not decline during the SIC procedure. Finally, we conduct the simulation to verify the analytical results.

关键词： error propagation (EP) successive interference cancellation (SIC) transmit correlation V-BLAST zero forcing (ZF)

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Compressed ghost imaging based on differential speckle patterns

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Chinese Physics B 2020年第2期29卷 294-300页

作者： Le Wang Shengmei Zhao Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications(NUPT)Nanjing 210003China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology(NUPT) Ministry of EducationNanjing 210003China

We propose a compressed ghost imaging scheme based on differential speckle patterns,named *** the scheme,a series of bucket detector signals are acquired when a series of random speckle patterns are employed to illuminate an unknown *** the differential speckle patterns(differential bucket detector signals)are obtained by taking the difference between present random speckle patterns(present bucket detector signals)and previous random speckle patterns(previous bucket detector signals).Finally,the image of object can be obtained directly by performing the compressed sensing algorithm on the differential speckle patterns and differential bucket detector *** experimental and simulated results reveal that CGI-DSP can improve the imaging quality and reduce the number of measurements comparing with the traditional compressed ghost imaging schemes because our scheme can remove the environmental illuminations efficiently.

关键词： ghost imaging compressed sensing differential speckle patterns differential bucket detector signals

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External Electric Field Effect on Hydrogenic Donor Impurity in Zinc-Blende InGaN Quantum Dot

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Chinese Physics Letters 2008年第8期25卷 3017-3020页

作者：姜黎明王海龙吴慧婷龚谦封松林 College of Physics and Engineering Qufu NormM University Qufu 273165 Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Micro-system and Information Technology Chinese Academy of Sciences Shanghai 200050

The binding energy of a hydrogenie donor impurity in zine-blende （ZB） InGaN quantum dot （QD） is calculated in the framework of effective-mass envelope-function theory using the plane wave basis. It is shown that the donor binding energy is highly dependent on the impurity position, QD size and the external electric field. The symmetry of the electron probability distribution is broken and the maximum of the donor binding energy is shifted from the centre of QD in the presence of the external electric field. The degenerating energy levels for symmetrical positions with respect to the centre of QD are split. The splitting increases with the increase of QD height while the splitting increases up to a maximum value and then decreases with the increase of QD radius.

关键词： the power-law exponents precipitation durative abrupt precipitation change

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Asymptotically maximum likelihood detection for subcarrier mapping-induced cyclostationary signatures in cognitive radio networks

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INTERNATIONAL JOURNAL OF communication SYSTEMS 2013年第8期26卷 1011-1027页

作者： Jiang, Yonglei Hu, Honglin Chinese Acad Sci Shanghai Res Ctr Wireless Commun WiCO Shanghai Inst Microsyst & Informat Technol SIMIT Key Lab Wireless Sensor Network & Commun Shanghai Peoples R China

In cognitive radio networks based on orthogonal frequency division multiplexing, the subcarrier mapping-induced cyclostationary signatures are utilized for robust network coordination. However, the effect of network coordination depends on the reliable detection of such cyclostationary signatures. Moreover, doubly selective fading increases the difficulty of reliable detection. In this paper, we first derive an exact covariance matrix to characterize the statistics of the cyclostationary signatures induced by subcarrier mapping. Using the exact covariance matrix rather than its estimation adopted in conventional algorithms, we propose an asymptotically maximum likelihood detection algorithm. The detection performance of the proposed asymptotically maximum likelihood detection algorithm is analyzed and evaluated both in flat fading and doubly selective fading channels. Simulation results show that the proposed algorithm outperforms the conventional low-complexity single-cycle signature detection algorithm in terms of less observation period or smaller mapping set size. Copyright (c) 2011 John Wiley & Sons, Ltd.

关键词： cognitive radio network coordination spectrum sensing cyclostationary signature subcarrier mapping maximum likelihood detection doubly selective fading

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Cyclostationarity-Based Frequency Synchronization for OFDM Systems Over Doubly-Selective Fading Channels

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wireless PERSONAL communicationS 2012年第2期66卷 461-472页

作者： Tian, Jinfeng Jiang, Yonglei Hu, Honglin Chinese Acad Sci Key Lab Wireless Sensor Network & Commun SIMIT Shanghai Peoples R China Shanghai Res Ctr Wireless Commun WiCO Shanghai 200335 Peoples R China

Orthogonal frequency division multiplexing (OFDM) systems are highly sensitive to carrier frequency offset (CFO), especially in doubly-selective fading environment. Cyclostationarity-based blind synchronization methods are appealing in high-data-rate applications and low signal-to-noise regions. However, the cyclostationarity has not been exploited for frequency synchronization of OFDM systems under doubly-selective fading channels. In this paper, we derive the close-form second order cyclic statistics of the received OFDM signal in presence of CFO, by modeling the doubly-selective fading channel with basis expansion model. Both transmitter-induced cyclostationarity and doubly-selective channel information are contained in the derived cyclic moments, and they are efficiently utilized for CFO estimation. Simulation results demonstrate that the proposed estimator provides significant improvements on frequency synchronization performance.

关键词： OFDM Frequency synchronization Cyclostationarity Doubly-selective fading channels

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TOA Localization in DDM-NLOS Propagation Environments: A Robust Optimization Approach

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2024年第12期73卷 19708-19720页

作者： Long, Yu Luo, Mei Sun, Hui Qin, Shuang Sichuan Normal Univ Key Lab Wireless Sensor Network Coll Phys & Elect Engn Univ Sichuan Prov Chengdu 610101 Peoples R China

In the presence of occlusion, the non-line-of-sight (NLOS) error has been proven to satisfy a distance-dependent model (DDM). However, existing DDM-based Time-of-Arrival (TOA) localization methods overfit due to their dependence on the exact linear coefficients in the model or assume that the linear coefficients are the same in all paths. In response to the defect, we represent the linear coefficients in matrix form and resort to robust optimization. Subsequently, we construct a second-order cone (SOC) programming with the linear coefficients matrix. To obtain a tractable robust optimization problem, we first convert the SOC constraint to a semi-definite cone (SDC) constraint using the Schur complement. Then, we decompose the SDC constraint with auxiliary variables. For the nonconvexity introduced by the linear coefficients matrix, we use Cauchy-Schwarz inequality and norm compatibility to eliminate the linear coefficients matrix. Finally, we convert a non-convex problem into a solvable semi-definite programming (SDP) problem. This study considers the linear coefficients as matrix variables, making the estimates accurate in densely cluttered environments and independent of precisely priori information about the linear coefficients. Simulations and experiments show better localization accuracy in complex environments than state-of-the-art algorithms.

关键词： Accuracy Location awareness Distance measurement Optimization Upper bound Matrix decomposition Matrix converters wireless localization non-line-of-sight propagation distance-dependent model robust optimization

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Improving the Performance of Practical Decoy-State Measurement-Device-Independent Quantum key Distribution with Biased Basis Choice

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communications in Theoretical Physics 2018年第9期69卷 331-336页

作者： Chun-Hui Zhang Chun-Mei Zhang Qin Wang Institute of Signal Processing Transmission Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network TechnologyNanjing University of Posts and TelecommunicationsMinistry of EducationNanjing 210003China

Statistical fluctuations are unavoidable in realistic quantum key distribution (QKD) due to finite-size effect. Based on the four-intensity proposal on measurement-device-independent QKD (MDI-QKD) in [Phys. Rev. A93 (2016) 042324], we particularly analyze the scenario that only three intensities are used, namely a three-intensity decoy-state MDI-QKD with biased basis choice. After performing full parameter optimization method, simulations results demonstrate that this scenario can obtain distinct enhancement compared with the conventional unbiased threeintensity decoy-state method, e.g. Xu et al.’s [Phys. Rev. A 89 (2014) 052333]. Furthermore, results also show that it works more efficiently by using HSPS than using WCS at longer transmission distance.

关键词： measurement-device-independent quantum key distribution statistical fluctuations biased basis choice

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