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In the paper, the distributed voltage and current on the transmission lines are calculated first by the maxwell's equations combining with HFSS. Then the distributed capacitances and inductances are extracted by substituting the distributed voltage and current into traditional transmission line equations. Finally, the differences of voltage, current and circuit parameters of the three kinds of chamfered bent lines are analyzed by electromagnetic theory.

In this paper, a second order Koch fractal log-periodic dipole antenna (LPK2DA) with broadband is proposed. Koch iteration technique has been applied here in order to obtain a small physical size. And the overall size of the proposed antenna is 57.5×88.9×0.5 mm3. The antenna has a broadband which ranges from 2 GHz to 8 GHz. Furthermore, the antenna has end-fire radiation patterns along its horizontal axis, which is very suitable for receiving antennas and conformal applications.

The traditional transmission line equations are applied to analyze the circuit parameters of the ladder-type lossless microstrip lines. The distributed capacitance and inductance of the ladder-type microstrip lines are extracted. By changing the structural and electric parameters of microstrip lines, the variation of distributed circuit with different substrate dielectric constants and cutting angles of ladder-type lines are obtained. Three kinds of transition angle (0°, 45°, 60°) and three kinds of dielectric constant (3.9, 4.2, 4.5), which are commonly used parameters in actual interconnector design, are discussed.

The objective of this paper is to present a quad-band antenna for handset application includes the effects of a metallic ring and a hand. We show that it is necessary to co-design the antenna and the ring together, since the metal ring has a significant influence on the performance of the antenna. The effect of the hand on the efficiency of the composite antenna and metal ring is investigated and it is shown that the radiation efficiency of the phone degrades rather significantly when the phone is gripped by the hand.

This paper investigates the scheduling problem in the aluminum twin roll casting process. The ultimate goal is to determine the sequence of aluminum coils considering the sequence-dependent setup cost caused by alloy, width, thickness of the adjacent coils and the orders’ specifications. A mixed integer linear programming model considers both the makespan and total tardiness is proposed to describe the problem. Since this problem and the mathematical model are very complex, a scatter search based heuristic is designed to solve the problem. Computational experiments show that the proposed method could get better solutions than the CPLEX software package.

In this paper, a low-profile RFID tag antenna designed for applications in UHF band is proposed. The antenna has planar structure, and its overall size is 60 × 26 × 0.8mm2. It has larger inductive reactance than other tag antennas, so it's easier to match with the Philips U-CODE Gen 2 RFID chip whose input impedance is 43-J800Ω at frequency of 915MHz. Measured and simulated results of the proposed antenna are in good agreement.

A low-profile array antenna composed of 2-turn helices with pitch angle of 4o is designed for the direct broadcast from satellite (DBS), it has a frequency band ranging from 11.5GHz to 13.0GHz. The antenna elements are fed by a radial waveguide in which a traveling wave in transverse electromagnetic (TEM) mode is propagating. The exciting phase of each helical element can be adjusted by rotating mechanically the element around its axis. Promising performances of the antenna are predicted theoretically first, and then the experiments are done for verifying the efficiency of the design.

An ultra-wideband antenna based on rectangular tempered ridge waveguide is presented in this paper. It consisted of a ground plane and a rectangular tempered ridge waveguide shape radiator designed on FR4 substrate with dielectric constant 4.4 and thickness 1.6 mm. The antenna is successfully designed, implemented, and measured. Simulation and measurement results are given and compared. Both results show that the return loss of the antenna less than −10 dB cover the frequency band for UWB applications. Far field radiation patterns of the antenna in xoy plane and xoz plane at 3.5 GHz, 7 GHz and 10 GHz are given respectively.

In this paper, a Quasi-Yagi antenna with a simplified feeding network is proposed. The impedance bandwidth, radiation patterns and gain of the proposed antenna are studied by the Finite Difference Time Domain (FDTD) method. The simulated and measured results show that the accomplished bandwidth of the antenna can cover a frequency range from 4.64 GHz to 6.25 GHz, which involves the two WLAN bands of 5.15 GHz to 5.25 GHz and 5.75 GHz to 5.85 GHz. Within the frequency band, the radiation characteristic of the antenna exhibits a good performance, and the maximum gain is about 7.2 dB. The antenna is easy to integrate with the microwave circuits and other solid devices.

A novel planar monopole antenna fed by a coplanar waveguide (CPW) for wireless communications in the wireless local-area network (WLAN) bands is studied, which is analyzed by the Finite Difference Time Domain Method (FDTD). The bandwidths defined by return loss less than −10 dB of the proposed antenna are about 1.21 GHz, from 2.27 to 3.48 GHz, and about 1.88 GHz, from 5.12 to 7 GHz. They can cover the frequency bands of 2.4, 5.2, and 5.8 GHz of WLAN. The antenna has been constructed and tested, and both theoretical and experimental results are presented and discussed.

A microstrip wide slot antenna with a notched frequency band is proposed. The antenna is with an E-shaped radiation patch and is fed by microstrip line, and to realize the band notching function, an E-shaped slot is cut in the E-shaped radiation patch. The Finite Difference Time Domain method is used in the analysis and the results of the FDTD are essentially in agreement with the experimental results. The antenna shows a low return loss within the UWB frequency band, excepting for the notched band from 4.98 to 5.57 GHz which is assigned to the wireless local area network systems. In addition to small size, the antenna also exhibits stable far-field pattern and omnidirectional radiation characteristics in horizontal plane.

A novel printed multi-band planar monopole antenna for mobile handsets is proposed and analyzed by the finite difference time domain method (FDTD). The radiating patch of the proposed antenna is designed jointly with the shape of ground plane. The proposed antenna with 36 mm in height and 50 mm in width was fabricated and tested, and its operating bandwidth defined by voltage standing wave ratio (VSWR) less than 2.5 covers the global system for mobile communication (GSM, 890-960 MHz), global positioning system (GPS, 1575.42 MHz), digital communication system (DCS, 1710-1880 MHz), and personal communication system (PCS, 1850-1990 MHz). Design details and experimental results are also presented and discussed.

A new structure of ultra-wideband antenna is proposed. The antenna consists of a ring strip connecting with two triangle patches as the ground, and a rectangular patch connecting with a strip as the radiator and feeding line. The antenna is fed by a coplanar waveguide. Simulated results gotten by FDTD method are given and compared with the experimental results. The results show that the antenna can cover a bandwidth from 2.8 to 11 GHz for return loss less than -10 dB.

A novel three-band printed monopole antenna is proposed, which is composed of three stacked T-shaped monopoles with different sizes, and is analyzed by using the Finite Difference Time Domain Method (FDTD). The proposed antenna was fabricated and tested. The simulated and experimental results of impedance bandwidths of the antenna can meet the demand of WLAN operations in the 2.4, 5.2, and 5.8 GHz bands. The antenna has a simple profile, and can easily be fed by 50 Ω microstrip line. Moreover, simulated and experimental results with different parameters of the antenna are given.

This paper introduces dual-mode bandpass filter with cross couplings and absorbing resonators. The responses of six electrical resonators & two absorbing resonators and eight electrical resonators are simulated. It is shown that the cross coupling and absorbing resonator can improve the cutoffs at the edge of the passband evidently. An L-band filter composed of three physical cylindrical waveguide cavities and one absorbing cavity was made and tuned. The experimental result is in good agreement with the simulation.

A novel high-power combiner/divider with compensation circuit is presented in this paper. The isolating resistor between two dividing ports in conventional Wilkinson power divider is replaced by a structure of coax balun transformer. With this coaxial structure, the bandwidth of this novel combiner is three times wider than a conventional one. It can be used in broadband and high-power combination. Simulation results of the conventional Wilkinson combiner, a bisection combiner and the novel combiner are given and compared in this paper.