Advanced Materials Research Vol. 529

Abstract: To analyze the inhibition to SSN, we use the design and emulation tools from Ansoft Co., which are used in the optimization design on PDS, integrated with particular circuit designs. Firstly, the traditional means of adding Decoupling Capacitor is adopted to inspect and verify that increased decoupling capacitors will help to increase high frequency response. Secondly, we introduce a high impedance electromagnetic surface texture, which can be applied to decrease SSN. Lastly, we support that EBG is better than traditional adding decoupling capacitor.

Abstract: The Galileo E5 signal is by far the most sophisticated signal among all the signals used for Global Navigation satellite system. Galileo receivers capable of tracking E5 will benefit from much better performance in terms of measurement accuracy and multipath suppression. Compared with traditional receivers for BPSK or even BOC signals, E5(AltBOC) signal processing techniques requires much more challenging due to the stems of the extremely large bandwidth and inherently complex correlations. This paper aims to present the receiving methodology and the architecture of tracking. The architecture of the tracking channel is discussed alongside with related algorithms and impact of code tracking jitter is evaluated finally.

Abstract: In this research, a triangular two-dimensional (2D) photonic crystal (PC) was hypothetically introduced into the active layer of a PbS quantum dots (QDs) electroluminescent (EL) device. The attributes of the photonic band gap effect and diffraction effect were considered and evaluated for device performance improvement. We designed and optimized the 2D-PC structure parameters to enhance the emission intensity at wavelength 1124 nm. The optimal structure parameter of PC is determined by normalized radius of r/a=0.49 and lattice constant of a=540 nm when the thickness of PC slab h is 74 nm. The 3D stimulation view of light propagation validates and supports the proposed strategy. The results provide a theoretical prediction for ideal PbS QDs-based EL device.

Abstract: The compounds of Fe substitution of Cr in nanotructured Sr2Fe1-xCrxMoO6 (0≤x≤0.2) double perovskite have been prepared by sol-gel method. And the x-ray diffraction patterns of the samples show that the samples are in nanometer range. All the samples show a paramagnetic to ferromagnetic transition with temperature, and the Curie temprature increase with the increasing of x. The resistivity of the samples decrease with the increasing of temprature, and increase with the increasing of x.

Abstract: In this paper, a novel method for pulse integration in radar-probing system is proposed to yield a low sidelobe response. According to m-sequence widely used in spread spectrum communication system, a bipolar pulse sequence is designed in this paper. At the receiving end, the envelop-detected signal is processed by a corresponding algorithm which dilutes the range sidelobe influence much. Because of the good autocorrelation and cross-correlation properties, waveforms yield a low sidelobe response and major lobe to side lobe ratio can reach 30dB or more, which is easy to satisfy the practical requirements. Simulation results show the good performance of the proposed approach. Furthermore, the approach is compatible to the conventional radars and can also be applied to the upgrade of radar.

Abstract: RS-232-C and a modem together, the interface can connect all kinds of different types of micro computer, so that they can direct communication. Nowadays more popular FANUC series CNC system, and the machine is equipped with a 25 injection of RS-232-C asynchronous serial communication interface standards, connect the computer and programmer and peripherals. With MAX232 chip design of interface circuit DB9.

Abstract: An analytical model for field-plate (FP) optimization in high electron mobility transistor (HEMT) is reported. With the potential distribution in device’s channel being modeled in terms of physical parameters, the two critical parameters of FP, i.e., the insulator thickness and the FP length, are optimized respectively. Using the model, the optimization of the FP structure in a typical undoped AlGaN/GaN HEMT is described in detail.

Abstract: Aiming at the problem of the traditional stator current frequency spectrum analysis method cannot completely guarantee the accurate identification of stator winding inter-turn faults,the diagnosis method of stator winding inter-turn based on wavelet packet analysis (WPA) and Back Propagation (BP) neural network is put forward. The finite element model of the three-phase asynchronous motor which is based on Magnet is established, and analysis the magnetic flux density and current of the motor through simulation in normal and in the situation of short-circuit fault of stator winding inter-turn, the current signal of stator is analysised by wavelet packet , and the feature vector of frequency band energy is extracted as the basis to judge the state of induction motor running, and the motor state is identified by BP neural network, and the mapping from feature vector to the motor state is established. Simulation results show that: The diagnosis system of inter-turn fault based on WPA and BP neural network can effectively identify short-circuit fault between ratios. This is to say that the method has a high fault diagnosis rate.

Abstract: Inductive coupled power transfer system is based on the principle of electromagnetic induction to transfer power from the primary side to the secondary side of a loosely coupled transformer, which can transfer electricity wirelessly. The loosely coupled transformer has large leakage inductance, which reduces the power transfer efficiency. In order to reduce the leakage inductance, a capacitance is used at the primary side and secondary side of a loosely coupled transformer, which can increase the power transfer efficiency. For four different compensation structures, this paper analyses the coupling coefficient and the secondary quality factor’s influence on the voltage gain, current gain and transfer efficiency, and also compares different compensation structures