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Deng F.-S.,Wuhan University | He S.-Y.,Wuhan University | Chen H.-T.,Wuhan Maritime Communication Research Institute | Hu W.-D.,National University of Defense Technology | And 2 more authors.
IEEE Transactions on Antennas and Propagation | Year: 2010

Numerical simulation of vector wave scattering from three-dimensional (3-D) target and rough surface composite model is investigated with a 3-D multilevel UV method. Due to the adoption of RWG basis functions for accurate modeling of vector current, the oscillation of the interaction matrix elements brings difficulty to directly apply the UV decomposition method. Based on the reordering of the interaction strength and the sampling according to the characteristics distribution of the interaction, an EM- interaction-based sampling algorithm is developed for the accurate reconstruction of the far interaction submatrix with UV decomposition method. Combined with multilevel division of the total composite model, the 3-D multilevel UV method incorporating the new sampling algorithm is developed for vector wave scattering from 3-D complex target above or on a random rough surface. The 3-D multilevel UV method yields a complexity of $O(N\log N)$ for the setup time of the impedance matrix, the solve time of the matrix iterative solution and also for the memory requirements. The accuracy and the efficiency of the 3-D multilevel UV method is compared and validated with the full MOM method and the ACA method in the tested cases. Finally, the applications of a target above or on the rough surface, for example, a ship on the sea surface, have been accomplished and analyzed. © 2006 IEEE.

Pan X.,Beihang University | Xin Z.,CAS Institute of Computing Technology | Li G.,Wuhan Maritime Communication Research Institute
IEEE Transactions on Reliability | Year: 2015

The IEEE Standard 1624 provides a foundation for the assessment of organizational reliability capability (ORC). However, to better match the individual characteristics of different industries, this standard needs to be suitably clipped and adjusted, so as to develop customized models for the reliability capability evaluations of different organizations. To evaluate the ORC of China's aviation enterprises effectively, we propose a reliability engineering capability maturity model (RE-CMM) for China's aviation industry, with adequate consideration of the features closely associated with China's aviation enterprises and China's military standards. The proposed RE-CMM model is established on the theoretical basis of Capability Maturity Model Integration (CMMI), combined with the IEEE standard and China's military standards for Reliability, Maintainability, and Supportability (RMS). Structural equation modeling (SEM) is used to verify the validity of the RE-CMM model. We use a fuzzy method for the evaluation of reliability engineering capability. Detailed steps of reliability engineering capability assessment are also provided for the application of the model. Finally, a case study on a Chinese aviation enterprise is given to illustrate the model and method. © 2015 IEEE.

Li J.,Wuhan University | He S.,Wuhan University | Yu D.,Wuhan University | Deng F.,Wuhan Maritime Communication Research Institute | And 2 more authors.
Optics Express | Year: 2011

A numerical matching method (NMM) based on the framework of the uniform geometrical theory of diffraction (UTD) is proposed to build the spectral functions for computing the diffraction field by anisotropic impedance wedge at an arbitrary skew incidence. The NMM starts from the coupled integral equations before they are converted into the coupled difference equations as the classic Maliuzhinets methods. Then, the spectral function in the Sommerfeld integral representation of the longitudinal components of the EM field is expanded by a series about the spectrum and the skew incident angle with unknown coefficients. With respect to the oblique incident angle based on normal to the edge incidence or grazing to the edge incidence, the spectral function is derived numerically by solving a system of algebraic equations constructed from the coupled integral equations, after choosing the numerical matching regions on the wedge faces and setting a Sommerfeld numerical integration path. On the basis of the sampled incidences, the asymptotic waveform evaluation (AWE) technique is employed to deduce the spectral function at any other skew incidence in the whole angle space (0°-90°) rapidly. Finally, the UTD solutions are provided far beyond the applicability of the perturbation approach and the numerical examples provide a uniform behavior of the field with respect to the observation angle. © 2011 Optical Society of America.

Liu X.,Wuhan Maritime Communication Research Institute
2011 China-Japan Joint Microwave Conference Proceedings, CJMW 2011 | Year: 2011

U-slot patch antenna with feeding and short-circuiting pins in abnormal shape is suitable for wideband (WB) and ultra wideband (UWB) systems, as well as array applications. A new WB antenna with dual-port supporting multi-band is developed by application of unique shape and perfect performance of the U-slot patch antenna in a skillful two-layer structure. The simulation result and the test model of the antenna are presented. Comparison of results between simulation and test are also provided. © 2011 CJMW.

Wang Y.,Harbin Engineering University | Liu J.,Harbin Engineering University | Liu J.,Wuhan Maritime Communication Research Institute
Journal of Convergence Information Technology | Year: 2012

In Mobile Ad hoc Networks(MANET), topological dynamic changes may lead to link failure frequently and consequent serious packets loss. Since traditional TCP protocol cannot distinguish between different types of packets loss and thus it incorrectly estimates network condition and blindly starts congestion control which will thus degrades the network performance. Therefore, a Dynamic Topology-Multipath AODV (DT-MAODV) applicable for dynamic topology environment is proposed to improve the performance of TCP in MANET in this paper. The AODV adopts link-disjoint path strategy to set up many backup routes. When a route breaks, it firstly takes advantage of available local backup paths to recover it in order to decrease frequency of route rebuilding. At the same time, data salvage mechanism is also introduced to increase delivery ratio of data packets. Simulation results indicate that DT-MAODV protocol can effectively decrease packet loss rate and improve throughput of TCP protocol compared with AODV and DSR.

Liu X.,Wuhan Maritime Communication Research Institute
2010 9th International Symposium on Antennas Propagation and EM Theory, ISAPE 2010 | Year: 2010

Microwave Low-profile E Shape Antenna is suitable for ultra wideband (UWB) communication system either independently or in array form. This article introduces the theory and experiment research of the UWB antenna model which can increase both of its impedance bandwidth and directional gain bandwidth. The simulation model and the test result are also presented. ©2010 IEEE.

Wu T.,Wuhan Maritime Communication Research Institute
Proceedings - 2015 IEEE 11th International Conference on ASIC, ASICON 2015 | Year: 2015

Elliptic curve point multiplication (ECPM) over prime fields has received much attention these years due to growing applications of public key cryptography. In this work we propose a parallel architecture to perform ECPM by Montgomery ladder algorithm. It consists of dual arithmetic cores carrying out pipelined modular multiplications, two-port block RAMs, the modular divider and the control unit. It can compute a 384-bit ECPM by 1.03 ms at 276 MHz in Xilinx Virtex-4 FPGA, costing 11883 slices, 26 DSPs, and 26 block RAMs(32×12). © 2015 IEEE.

Liu X.,Wuhan Maritime Communication Research Institute
2010 IEEE International Conference on Ultra-Wideband, ICUWB2010 - Proceedings | Year: 2010

Microwave U-slot patch antenna with a shorting pin is suitable for ultra wideband (UWB) communication system. This article introduces the simulation and the experiment of the UWB antenna model which increases its impedance bandwidth and gain bandwidth. The antenna bandwidth is expanded by the diversification designed for the shorting pin and the feed pin. The simulation model and the test result are also presented and the results are found in well agreement. The impedance bandwidth of the antenna is compared with that of reference [1]. The research has made big advancement in expanding antenna bandwidth. © 2010 IEEE.

Yang L.,Wuhan Maritime Communication Research Institute
Information Technology Journal | Year: 2013

In allusion to the problem of load balance, differentiated priority of service and guaranteeing the QoS performance of high priority service, a new route protocol for MANET-MDSRP (Mobile Differentiated Service Route Protocol) was proposed. MDSRP makes use of a new kind of route metric, EWDM (Expected Waiting Delay Metric). With this new metric the MDSRP can measure and evaluate the end-to-end delay of every candidate route and offer different strategies for service with different priorities. According to this mechanism, MDSRP can also balance the traffic load of networks to avoid the congestion in regional area. Analysis and simulation results had shown the feasibility and effectiveness of MDSRP.

Yuan L.,Wuhan Maritime Communication Research Institute
Proceedings - 2011 IEEE International Conference on Computer Science and Automation Engineering, CSAE 2011 | Year: 2011

Heterogeneous wireless network interconnection is one of the hot points of the current research. A novel interconnection strategy based on IP switching is put forward in this paper. The core modules are discussed seriously. And two interconnection methods, IP encapsulation and IP mapping, are proved effectiveness through the simulation results. © 2011 IEEE.

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