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Improved dichotomous search frequency offset estimator for burst-mode continuous phase modulation
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作者 翟文超 李赞 +1 位作者 司江勃 柏均 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期584-591,共8页
A data-aided technique for cartier frequency offset estimation with continuous phase modulation (CPM) in burst- mode transmission is presented. The proposed technique first exploits a special pilot sequence, or trai... A data-aided technique for cartier frequency offset estimation with continuous phase modulation (CPM) in burst- mode transmission is presented. The proposed technique first exploits a special pilot sequence, or training sequence, to form a sinusoidal waveform. Then, an improved dichotomous search frequency offset estimator is introduced to determine the frequency offset using the sinusoid. Theoretical analysis and simulation results indicate that our estimator is noteworthy in the following aspects. First, the estimator can operate independently of timing recovery. Second, it has relatively low outlier, i.e., the minimum signal-to-noise ratio (SNR) required to guarantee estimation accuracy. Finally, the most important property is that our estimator is complexity-reduced compared to the existing dichotomous search methods: it eliminates the need for fast Fourier transform (FFT) and modulation removal, and exhibits faster convergence rate without accuracy degradation. 展开更多
关键词 frequency offset estimation Cramer-Rao bound dichotomous search continuous phase modulation
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A reduced state SISO iterative decoding algorithm for serially concatenated continuous phase modulation 被引量:1
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作者 SUN JinHua LI JianDong JIN LiJun 《Science in China(Series F)》 2007年第4期539-550,共12页
In this paper, serially concatenated continuous phase modulation (SCCPM) system is analyzed and a reduced state soft input soft output (SlSO) a posteriori probability algorithm is proposed. Based on the reduced st... In this paper, serially concatenated continuous phase modulation (SCCPM) system is analyzed and a reduced state soft input soft output (SlSO) a posteriori probability algorithm is proposed. Based on the reduced state sequence detection (RSSD), it has the more general form compared with other reduced state SISO algorithms. The proposed algorithm can greatly reduce the state number, thus leads to the computation complexity reduction. It also minimizes the degradation in Euclidean distance with decision feedback in the reduced state trellis. Analysis and simulation results show that the performance degradation is little with proper reduction scheme. 展开更多
关键词 concatenated codes continuous phase modulation (CPM) soft input soft output (SISO) Euclidean distance
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Fabrication of a large-aperture continuous phase plate in two modes using atmospheric pressure plasma processing 被引量:1
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作者 苏星 夏龙光 +4 位作者 刘刊 张鹏 李平 赵润昌 王波 《Chinese Optics Letters》 SCIE EI CAS CSCD 2018年第10期65-69,共5页
In order to fabricate a large-aperture continuous phase plate(CPP) using atmospheric pressure plasma processing(APPP) with high efficiency and precision, the position dwell mode and velocity mode were proposed and... In order to fabricate a large-aperture continuous phase plate(CPP) using atmospheric pressure plasma processing(APPP) with high efficiency and precision, the position dwell mode and velocity mode were proposed and the iterative calculation method was developed for the non-constant removal rate. Two 320 mm × 320 mm × 2 mm CPPs were fabricated with two processing modes. The experiment results show that the velocity mode is capable of significantly reducing the processing time and shape error. The total processing time is decreased from 13.2 h to 9.3 h, and the surface shape error is decreased from 0.158λ to 0.119λ(λ = 632.8 nm)(root mean square). 展开更多
关键词 Fabrication of a large-aperture continuous phase plate in two modes using atmospheric pressure plasma processing CPP
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THE TEMPERATURE ANALYSIS OF THE BILLET WITH PHASE CHANGE DURING CONTINUOUS CASTING
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作者 赵兴华 陈小弟 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第2期109-118,共10页
In this paper,the problem of 3-D steady heat conduction including the influenceof phase change on billets is turned into the 2-D transient problem by a suitable transformation technique. The effective specific heat ha... In this paper,the problem of 3-D steady heat conduction including the influenceof phase change on billets is turned into the 2-D transient problem by a suitable transformation technique. The effective specific heat has been employed to substitutefor the effect of the phase ceange.The computational formulation of finite element has been presented. And the careful disposal of the phase change region has also beengiven. 展开更多
关键词 continuous casting.phase change.temperature field
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DESIGN OF DIGITAL IMPACTING FILTER IN CP-EBPSK WITH RANDOM-POLAR COMMUNICATION SYSTEM 被引量:4
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作者 Jin Yi Wu Lenan +1 位作者 Chen Yifang Yu Jing 《Journal of Electronics(China)》 2012年第3期328-333,共6页
To solve the difficulty of designing digital impacting filter in the receiver of random-polar modulated Extended Binary Phase Shift Keying with Continuous Phase (CP-EBPSK), a design method based on Quantum-behaved Par... To solve the difficulty of designing digital impacting filter in the receiver of random-polar modulated Extended Binary Phase Shift Keying with Continuous Phase (CP-EBPSK), a design method based on Quantum-behaved Particle Swarm Optimization (QPSO) algorithm is proposed. Firstly, QPSO is introduced elaborately, and the basic flow of QPSO is also given. Then, the demodulation principle of digital impacting filter in the communication system of CP-EBPSK with random-polar is demonstrated, and QPSO is utilized to design the digital impacting filter, which also takes the effect of finite word length into consideration when implemented by hardware. Finally, the proposed method is simulated. Simulation results show that the digital impacting filter designed by new method can derive satisfied demodulation performance. 展开更多
关键词 Extended Binary phase Shift Keying with continuous phase (CP-EBPSK) Digital impacting filter Quantum-behaved Particle Swarm Optimization algorithm (QPSO) DEMODULATION Effect of finite word length
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Improved iterative convergence method in Q-ary LDPC coded high order PR-CPM
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作者 Danfeng Zhao Yanbo Sun Rui Xue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第3期541-548,共8页
The Q-ary low-density parity-check(LDPC) coded high order partial response continuous phase modulation(PR-CPM) with double iterative loops is investigated. This scheme shows significant improvements in power and b... The Q-ary low-density parity-check(LDPC) coded high order partial response continuous phase modulation(PR-CPM) with double iterative loops is investigated. This scheme shows significant improvements in power and bandwidth efficiency, but at the expense of long iterative decoding delay and computational complexity induced by the improper match between the demodulator and the decoder. To address this issue, the convergence behavior of Q-ary LDPC coded CPM is investigated for the Q=2 and Q〉2 cases, and an optimized design method based on the extrinsic information transfer chart is proposed to improve the systematic iterative efficiency. Simulation results demonstrate that the proposed method can achieve a perfect tradeoff between iterative decoding delay and bit error rate performance to satisfy real-time applications. 展开更多
关键词 iterative detection convergence low-density paritycheck(LDPC) code continuous phase modulation(CPM) extrinsic information transfer chart
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Assessment of Health-Related Quality of Life of Tuberculosis Patients in Fako Division, South-West Region of Cameroon
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作者 Benjamin D. Thumamo Pokam Pius Fokam +2 位作者 Theophile Nana Njamen Prisca Wabo Guemdjom Anne E. Asuquo 《Journal of Tuberculosis Research》 2020年第3期93-110,共18页
<b>Background: </b>Tuberculosis (TB) caused by <i>Mycobacterium tuberculosis </i>is one of the top 10 causes of death worldwide. Despite the global impact of TB and treatment received, a gap pe... <b>Background: </b>Tuberculosis (TB) caused by <i>Mycobacterium tuberculosis </i>is one of the top 10 causes of death worldwide. Despite the global impact of TB and treatment received, a gap persists between treatment and quality of life of the patients especially in resource limited countries. This study therefore evaluated the health related quality of life of TB patients and the different factors influencing their quality of life at the post intensive phase of their treatment in the Fako division of the South-West Region of Cameroon. <b>Methods: </b>A hospital based cross sectional study was carried out in 4 tuberculosis treatment centers, namely two regional (Buea and Limbe) and two district (Tiko and Muyuka) hospitals in Fako Division between June and July 2017. One hundred and sixty-seven TB patients were enrolled in the study and relevant information from them was gathered using the SF-36 questionnaire. Various aspects such as their perception of the disease, their socio-demographics and socio-economics conditions were evaluated. <b>Results: </b>Of the 167 participants enrolled in the study, 95 (56.9%) were male and 72 (43.1%) were female. One hundred and thirty-three (79.6%) of the 167 participants were affected by pulmonary tuberculosis and 34 (20.4%) by extra-pulmonary tuberculosis. Fifty-five (32.9%) were HIV positive and 90 (53.9%) had been receiving treatment for 4 - 6 months, 73 (43.7%) for 1 - 3 months and 4 (2.4%) for 7 - 9 months. The lowest and highest scores were recorded on the role limitation due to emotional problems scale (30.54 ± 35.36), and on the social functioning scale (47.68 ± 16.33) respectively. There was a significant difference (p = 0.021), between pulmonary and extra pulmonary tuberculosis (49.15 ± 16.08 vs. 41.91 ± 16.25) on the social functioning. Financial difficulty restraining drug collection affected the general health perception (p = 0.003), vitality (p = 0.007), emotional well-being (p < 0.001) and social functioning (p = 0.05) of the patients. Low income affected the vitality (p = 0.039), emotional well-being (p = 0.015), role limitations due to physical (p = 0.046) and emotional (p = 0.003) problems of the patients. Equally, the HIV status affected their vitality (p < 0.001) and emotional well-being (p = 0.011). <b>Conclusion:</b> The quality of life of the TB patients in the study area was generally poor. Counselling of diagnosed TB patients and provision of financial assistance through a social package can improve the acceptance of the disease during their treatment period to avoid default and relapse. 展开更多
关键词 TUBERCULOSIS Quality of Life Continuation phase of Treatment SF-36 Questionnaire South West Region Cameroon
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Preliminary Study of Reconstruction of a Dynamic System Using an One-Dimensional Time Series
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作者 彭永清 朱育峰 严绍瑾 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1994年第3期277-284,共8页
This paper concerns the reconstruction of a dynamic system based on phase space continuation of monthly meantemperature iD time series and the assumption that the equation for the time-varying evolution of phase space... This paper concerns the reconstruction of a dynamic system based on phase space continuation of monthly meantemperature iD time series and the assumption that the equation for the time-varying evolution of phase space statevariables contains linear and nonlinear quadratic terms. followed by the fitting of the dataset subjected to continuation so as to get, by the least square method. the coefficients of the terms, of which those of greater variance contribution are retained for use. Results show that the obtained low-order system may be used to describe nonlinear properties of the short range climate variation shown by monthly mean temperature series. 展开更多
关键词 Monthly mean temperature Time series phase space continuation Dynamic system
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A Nonlinear Time-lag Differential Equation Model for Predicting Monthly Precipitation
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作者 彭永清 严绍谨 王同美 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第3期319-324,共6页
This paper investigates the nonlinear prediction of monthly rainfall time series which consists of phase space continuation of one-dimensional sequence, followed by least-square determination of the coefficients for t... This paper investigates the nonlinear prediction of monthly rainfall time series which consists of phase space continuation of one-dimensional sequence, followed by least-square determination of the coefficients for the terms ofthe time-lag differential equation model and then fitting of the prognostic expression is made to 1951-1980 monthlyrainfall datasets from Changsha station. Results show that the model is likely to describe the nonlinearity of the allnual cycle of precipitation on a monthly basis and to provide a basis for flood prevention and drought combating forthe wet season. 展开更多
关键词 Monthly rainfall phase space continuation Time-lag differential equation
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A STUDY OF DYNAMIC SYSTEM ESTABLISHMENT IN EOF-CONTINUATION PHASE SPACE
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作者 朱育峰 彭永清 +1 位作者 严绍瑾 张勤 《Acta meteorologica Sinica》 SCIE 1996年第1期52-60,共9页
For the EOF decomposition continuation phase space, the least square method is applied under the condition of orthogonal basis to find coefficients of all quadratic nonlinear terms of a state evo- lution equation such... For the EOF decomposition continuation phase space, the least square method is applied under the condition of orthogonal basis to find coefficients of all quadratic nonlinear terms of a state evo- lution equation such that a dynamic system that indicates the evolution features of a weather/cli- mate system in a limited area can be formulated. The scheme is compared with that for phase space continuation by time series drift. Results show that the dynamic system established in terms of the present method is likely to give more precise and realistic description of evolution of the weather/ climate system. 展开更多
关键词 empirical orthogonal function (EOF) decomposition phase space continuation dynamic system reconstruction
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Low-complexity detection based on maximum cumulative measure and Laurent decomposition for multi-h CPM signal
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作者 Zheng Zhidong Yu Yanming +2 位作者 Liu Ning Yuan Honggang Lou Ning 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2022年第6期64-72,共9页
In order to solve the problem of high computational complexity in demodulation for multi-h continuous phase modulation(CPM) signal, a maximum cumulative measure combing with the Laurent decomposition(MCM-LD) scheme is... In order to solve the problem of high computational complexity in demodulation for multi-h continuous phase modulation(CPM) signal, a maximum cumulative measure combing with the Laurent decomposition(MCM-LD) scheme is proposed to reduce the number of the grid states and the required number of matched filters, which degrades the demodulation complexity at the receiver.The advanced range telemetry(ARTM) Tier Ⅱ CPM signal is adopted to evaluate the performance in simulation. The results show that, compared with the traditional maximum likelihood sequence detection(MLSD), MCM-LD can respectively reduce the numbers of grid states and matched filters from 256 to 32 and 128 to 48 with negligible performance loss, which effectively degrades the computational complexity for multi-h CPM signal. 展开更多
关键词 multi-h continuous phase modulation(CPM) Laurent decomposition(LD) maximum cumulative measure(CM) low-complexity demodulation
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