Compact Dual-Band Bandpass Filter Using Stubs Loaded Ring Resonator

This paper presents a novel second-order dual-band bandpass filter (BPF) by using proposed stubs loaded ring resonator. The resonant behavior of proposed stubs loaded ring resonator is analyzed by even-/odd-mode method, which shows its multiple-mode resonant characteristic. Parameters sweep is done so as to give the design guidelines. As an example, a second-order dual-band BPF operating at 1.8/5.2 GHz for GSM and WLAN applications is designed, fabricated and measured. The fabricated filter has a very compact size of 0.05λg×0.15λg. Measured results also show that the proposed dual-band BPF has a better than 20 dB rejection upper stopband from 5.47 GHz to 12.56 GHz. Good agreement is shown between the simulated and measured results.

BENDING AND CRUMPLING DEFORMATION STUDY OF THE RESONANT CHARACTERISTIC AND SAR FOR A 2.4 GHZ TEXTILE ANTENNA

Over recent years, there has been an explosive growth of interest in the development of flexible wearable antennas due to rapid growth in Wireless Body Area Network (WBAN) applications. However, the antenna is subjected to deformation when being worn by users. Therefore, it is compulsory to analyze the absorption of electromagnetic (EM) radiation and the antenna performances as a function of the deformation conditions since the antenna is not in its normal flat conditions anymore. In this paper, two types of deformations; bending and crumpling are analyzed by means of CST Microwave Studio. The peak SAR10g demonstrates increment up to 65.7 % and 48.7 % under bending and crumpling deformation respectively. Moreover, the crumpling is more sensitive to the geometrical shape and composition of the exposed body area if compared to bending. Moreover, the detuning effects of the resonant frequency are more significant for crumpling cases.

Resonance Analysis of High-Frequency Electrohydraulic Exciter Controlled by 2D Valve

The resonant characteristic of hydraulic system has not been described yet because it is necessarily restricted by linear assumptions in classical fluid theory. A way of the resonance analysis is presented for an electrohydraulic exciter controlled by 2D valve. The block diagram of this excitation system is established by extracting nonlinear parts from the traditional linearization analysis; as a result the resonant frequency is obtained. According to input energy from oil source which is equal to the reverse energy to oil source, load pressure and load flow are solved analytically as the working frequency reaches the natural frequency. The analytical expression of resonant peak is also derived without damping. Finally, the experimental system is built to verify the theoretical analysis. The initial research on resonant characteristic will lay theoretical foundation and make useful complement for resonance phenomena of classical fluid theory in hydraulic system.

The Achievement of Dynamic Load Simulator of Servo Mechanism of Multiple DOF Thrust Vector

In order to better analyze the load resonant characteristic of thrust vector servo mechanism of spacecrafts, multiple DOF mathematical models were established. Combined with the need of simulated actual conditions for ground tests, a comprehensive load simulator containing mechanical and hydraulic load was presented. The simulation results show that, the dynamic characteristics of output load displacement of the simulator is in agreement with the characteristics of actual system. The simulation and experimental results verify the feasibility of this load simulator structure, which could provide design reference for developing equipment of thrust vector control system for ground tests.