Applied Mechanics and Materials Vols. 336-338

Abstract: This paper focuses on design aspect of communication network for feeder automation applications. First, the business functional requirements of feeder automation and the supporting communication technologies are reviewed. Then, based on typical loop sectionalizing feeder connecting scheme, the communication infrastructure using Ethernet Passive Optical Networks (EPONs) is presented, and the redundant PON architecture is adopted.

Abstract: WirelessHART, a kind of wireless mesh communication network that suits process automation, are widely used in the industrial fields. Routing algorithm performance directly determines sensor nodes how to transfer and control data, and the effective data rate. The algorithm which affects the energy consumption and lifetime of the whole sensor network is the core content of the network layer. WirelessHART network layer routing algorithm includes Source Route and Graph Route. In this paper, WirelessHART routing algorithm is simulated using nesC language in the TinyOS, and then compares with AODV protocol. And the data of experiment show the application advantage of WirelessHART Graph Route.

Abstract: Channel allocation based on multi-interface is a very important and difficult problem. Network throughput needs to be maximized while full consideration should be given to interference reduction and network connectivity. To solve this problem, the extended conflict graph was utilized to establish the link interference matrix; the frequency assignment technique in spectrum management based on greedy algorithm was introduced for channel allocation, and a channel assignment algorithm based on minimum interference was proposed. The algorithm fully considered link interference situation, and selected the link which currently suffers the minimum interference. For the selected link, select the idle channels when there are sufficient channels; select the channels with least potential interference when there are no idle channels. Based on this strategy, the link interference is effectively reduced, the number of links that can work simultaneously is increased, which fully maintained the connectivity of the network and effectively improved network throughput. Simulation results show that this scheme can effectively improve the performance of overall network.

Abstract: In a novel infrared/microwave co-aperture simulator design, tetrad of antenna array was adapted to synthesize the microwave target or interference signal. Based on the analysis of the influence of channels amplitude and phase errors on simulation precision of target position, a feed network and its control process was put forward. In the control process, the phase of the four channels signals fed to tetrad of antenna array was kept constant while adjusting the amplitude. To guarantee the position simulation accuracy, the amplitude and phase unbalance of the four channels was measured and revised in advanced in control process, and an iterative algorithm was designed to improve the position simulation accuracy at the same time.

Abstract: The technology of infrared wireless communication offers us a wireless connection and communication mode that is low cost, high speed and short distance. IrDA infrared data association brings forward IrDA infrared communication protocol that is the base of a large number of equipments, interlink with infrared data interface. This paper introduces IrDA standard and the frame structure of IrDA standard. An improve analysis is presented linking processor of IrLAP.

Abstract: This paper presents an architecture for 32-bit datapath Advanced Encryption Standard(AES) IP core based on FPGA. It uses finite state machine, and supports encryption, decryption and key expansion. The round-key is calculated before the beginning of encryption and decryption. It consumes less hardware resources. It is implemented on Cyclone II FPGA EP2C35F672C6, which consumes less than 55% logic elements of the resources. The IP core can operate at a maximum clock frequency of 100 MHz. Compared with 128-bit datapath AES, it can interface with CPU easily.

Abstract: In this paper, the new 4-moduli set {2²ⁿ, 2²ⁿ⁺¹-1, 2ⁿ+1, 2ⁿ-1} with 6n-bit DR, which is appropriate for RNS applications. An efficient algorithm for residue-to-binary conver­sion is derived based on New Chinese remainder theorem II (New CRT-II). Next, the converter hardware is also designed to achieve average 36.6% performance saving in terms of the Area× Delay when comparing with the latest converter with 4-moduli set under the same DR require­ment.

Abstract: Actual reflector antenna always has a deformation which has a serious influence on antenna performance. Establishing the equation of the distorted reflector surface is important for calculating antenna performance and precise control. A new best-fitting method based on least square method is submitted in this paper. This method depart from the ideal parabolic equation, and use the distance between the deformation point and the correspondent fitting point to establish the least square error condition equations, though which the six parameters can be got to determine the geometry position of the deformed parabolic accurately. Matrix operation can make the algorithm easy to realize in computer. Nan-shan 25m antennas finite element model is established in ANSYS program, and its result is analyzed compared with another method, confirmed the operability and accuracy of this algorithm.

Abstract: During the operation of transmission line communication system, the software failure is a very important and difficult issues. The event, usually requires a manual reset troubleshooting by climbing the pylons. This article describes the hardware watchdog technology , which can obtain high reliability and effectively reduce the cost of equipment maintenance for communication devices.

Abstract: In this paper, an improved kernel independent component analysis (KICA) algorithm is proposed for multi-user detection (MUD). In this algorithm, a new hybrid kernel function is adopted. In addition, the bat algorithm is applied to the optimizing process of independent component separation. Simulation results show that the new hybrid kernel function performs better in MUD than other kernel functions, and the improved KICA with bat algorithm has the smallest bit error rate (BER) when compared with classical FastICA and KICA algorithms.