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In this paper, we propose a novel structure using different code system division multiple access (DCSDMA) for an optical communication system and a design algorithm to increase the system capacity. This DCSDMA system can transmit two kinds of code systems (for example, the prime code of 7 and 3, respectively). This multicode architecture can improve the theoretical system capacity from P72 to P72+5∗P32. In this paper, we propose an optimal design method to find the simultaneous capacity X%∗72+Y%∗5∗32. X% and Y% are the successful percentages determined by the simulation results. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 291–295, 1999. [ABSTRACT FROM AUTHOR]

In FDTD simulations, the excitation sources can be divided into two categories: (i) the displacement-current source, which is generated by a time-varying electric field; (ii) the induced-current source, which exists in the lossy material. Currently, the latter source is the popular choice in most FDTD simulations. However, there are two problems with the use of this source: the time signal shape at the observation points is different from that of the input pulse, and an artificial DC component is introduced into the solution that prevents the solution from converging to zero. The objective of this paper is to investigate these excitation sources and to clarify some concepts in FDTD simulations. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 203–207, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20770 [ABSTRACT FROM AUTHOR]

In this paper, an efficient numerical simulation technique is introduced to extract the propagation characteristics of interconnects over lossy substrate structures. This approach is based on a compact-form FDFD method in conjunction with the two-step Lanczos (TSL) technique. The efficiency and accuracy of the algorithm are demonstrated through the simulation of several lossy transmission-line structures. [ABSTRACT FROM AUTHOR]

In this paper, the hybrid implicit–explicit finite-difference time-domain (HIE-FDTD) algorithm for a two-dimensional (2D) TE wave is extended to a full three-dimensional (3D) wave. The weakly conditional stability is verified by numerical simulation results. Numerical formulations of the 3D HIE-FDTD method are presented and simulation results are compared to those using the conventional 3D finite-difference time-domain method. High computation efficiency is obtained by introducing an unequal space increment in different dimensions in the HIE-FDTD method. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2291–2294, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21898 [ABSTRACT FROM AUTHOR]

An amplitude approaching algorithm (AAA) for the pattern synthesis of adaptive arrays is presented in this paper. Furthermore, the algorithm is amended by the Newton downhill method. Simulations show that the main lobe and side lobe can be controlled efficiently, and the algorithm converges more quickly and steadily. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 503–507, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10804 [ABSTRACT FROM AUTHOR]

The Thompson–FDTD method, which combines the differential-Thompson transformation involved in hydromechanics with the finite-difference time-domain (FDTD) technique, is introduced to simulate the electromagnetic scattering properties of arbitrarily shaped dielectric media in this paper. This method has at least two obvious advantages. First, it is able to transform an arbitrarily shaped body into a regular structure which accurately matches the boundary conditions; second, the mesh arrangement can be adjusted according to the scatterer's shape to achieve better numerical accuracy. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 28: 351–354, 2001. [ABSTRACT FROM AUTHOR]

The analysis and simulation of conformal microstrip antennas on arbitrary curved surfaces are always a difficult task. The complexity of the electromagnetic equations and the cost of real experiments plead in favor of new kinds of simulations. This paper presents a fast and accurate symbolic algorithm allowing the analysis and synthesis of spherical microstrip antennas. Comparison with experiments and theoretical results of other authors are discussed. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 20: 274–280, 1999. [ABSTRACT FROM AUTHOR]

The interconnections used in packaging of modern circuits introduce the delays that are comparable or even greater than the delays of gates. This causes the degradation of overall system performance. One may choose to solve the problem of delay by increasing the density of the system. This however, introduces the problem of "crosstalk." The analysis of delay and crosstalk in a system of interconnections requires the use of computer simulation. This paper introduces a very efficient and flexible timedomain analysis technique to predict the reflections and crosstalks. Numerical results show that this technique is indeed efficient and accurate in the transient analysis of general multiple coupled-line systems. The algorithm yields an equivalent linear hybrid n-port network for the interconnection system that facilitates the analysis of interconnections together with driving and receiving circuits with the aid of standard network analyzers like, for example, SPICE. [ABSTRACT FROM AUTHOR]

In this paper, three-dimensional optical computerized tomography in the case of severely incomplete projection data is discussed theoretically and experimentally. An orthogonal projection method has been proposed for optical tomography in the case of severely incomplete data. Some comparative numerical simulations and experimental results of traditional sampling method and the new method are given. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 57–59, 2001. [ABSTRACT FROM AUTHOR]

A compression algorithm is presented for discrete representations of boundary-integral operators. The algorithm relies on an expansion of the unknown surface currents in a numerically determined basis of functions that are simultaneously localized to small regions on a large target while also satisfying global boundary conditions. It is shown that the resulting local–global solution (LOGOS) modes provide efficient approximations of the impedance matrix at low to moderate frequencies. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 236–240, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21135 [ABSTRACT FROM AUTHOR]

The aggressive space mapping (ASM) algorithm is applied to the optimization design of LTCC filters. The partial element equivalent circuit (PEEC) method is utilized as a coarse model. Low-pass and band-pass LTCC filters are designed with HFSS and IE3D adopted as the fine models, respectively. Conductor thickness is taken into account, since it is fairly large with respect to dielectric height. Only a few instances of fine-model simulation are needed. [ABSTRACT FROM AUTHOR]

We propose a new and efficient numerical algorithm to simulate DWDM transmission systems amplified by backward multi-wavelength-pumped Raman amplifiers. In this model, system impacts caused by dispersion, nonlinearity, and ASE are considered, and calculated results have satisfying accuracy. As an application, we model a 64 × 10 Gb/s Raman broadband multi-span system, and arrive at some useful conclusions. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 35: 333–337, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10599 [ABSTRACT FROM AUTHOR]

ABSTRACT A novel unequal spacing multipulses technology for pulse Laser Radar was proposed in this article. Data accumulation technology is an efficient method to improve signal-to-noise ratio due to different statistical characteristics between the echo signal and the noise. Traditional multipulses technology using equal spaces multipulses always leads to outputs once the time window has pulses no matter the number of pulses. We proposed a method using unequal spaces multipulses technology to improve the poor performance of the equal space multipulses technology, that is, if and only if the time window had special number pulses, the novel system would have output signal. We discussed the method to generate unequal spacing multipulses serials first, and then the algorithm to deal with the echo signals was also illustrated. Both simulation and experimental results showed the validity of our algorithm. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1614-1620, 2015 [ABSTRACT FROM AUTHOR]

The matrix rotation technique is applied to the three-dimensional (3-D) multilevel fast multipole algorithm (MLFMA) at very low frequencies (LF) to save the storage without increasing the order of the floating-point operations. Some symmetrical properties of the translation matrices along the z-direction for the 3-D LF–MLFMA and the static MLFMA are also derived to further reduce the memory requirements. Numerical results shown that the order of errors introduced by the matrix rotation is much smaller than the order of errors from the plain LF–MLFMA or plain static MLFMA. The implementation of the matrix rotation technique does not change the precision order of the LF–MLFMA and the static MLFMA for fixed truncation of multipole expansions. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 26: 105–110, 2000. [ABSTRACT FROM AUTHOR]

A normalized three-dimensional (3-D) multilevel fast multipole algorithm (MLFMA) with a computational complexity of O(N) for very low-frequency (LF) problems is developed. This 3-D LF-MLFMA can be used not only independently for very low-frequency cases or very small structures compared to the wavelength, but also to solve large-scale structures with rapidly varying areas when merged with a general dynamic algorithm. From the LF–MLFMA, a more explicit and succinct representation of the static MLFMA is also derived. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 26: 43–48, 2000. [ABSTRACT FROM AUTHOR]