Advanced Materials Research Vols. 765-767

Abstract: The Ultra Wideband signal with multiple multipath component and use the Rake receiver can combine energy of multipath components. Using Rake reception, the performance of three kinds of receiving methods is compared with binary Ultra Wideband signal using the Maximal Ratio Combining (MRC), and got the simulation results.

Abstract: The quality of sleep has a great relationship with health. The result of sleep stage classification is an important indicator to measure the quality of sleep. It was found that the symbolic transfer entropy about wake and the first stage of non-rapid eye movement sleep reflect on the changes of sleep stage. And it was confirmed by T test and multi-samples experiments. The symbolic transfer entropy can apply into automatic sleep stage classification. By Multi-parameter analysis it could achieve a higher accuracy of sleep stage classification.

Abstract: The femtocell technology has spurred much interest both in research field and industrial area. There would be a widespread employment of femtocell access points (FAPs) in residential environment in near future. However, in a typical residential buildings with two rows of apartments which have femtocell access points (FAPs) installed and a long and narrow corridor in between, the Signal to Interference Plus Noise Ratio (SINR) of macrocell signal for passengers would be degraded dramatically that practical communicaitons would be impossible. It seems that access to nearby FAPs would be the only plausible solution. However, access to the strongest pilot FAP maybe inefficient in this dense FAPs employment environment. In this thesis, comparisons between different downlink access methods for FAPs based on OFDMA in dense employment residential environment have been made and their respective data rate and outage probability have been achieved.

Abstract: GNSS navigation has its own advantages which make researchers focus on how to effectively receive and process GNSS signals. This typically needs to utilize flexible specialized radio frequency front-ends, and we need to investigate novel software solutions. Due to the good performance of the Galileo E5 signal, the study of its acquisition, tracking and multipath mitigation has become increasingly significant. This paper has developed a customized 100MHz wide-band GNSS front-end. Three wide-band datasets of Galileo E5 signal were collected for case study. Final acquisition and tracking results of Galileo E5a signal successfully verified this customized RF front-end usability. It offers great potential for further studying the multi-constellation GNSS compatibility and interoperability to achieve high accuracy and continuity of GNSS navigation.

Abstract: It is difficult to study the characteristics of high speed optical communication system due to the complexity and high-cost in configuration. In this paper, aiming to overcome the weakness above, the performance of a 10Gbps optical communication system with single channel is investigated by simulation. Then, based on the outputs of RZ and NRZ codes modulated, an extensive comparison is developed in terms of spectrums, noises, eye diagrams and bit error rate.

Abstract: A hybrid M-ary spread spectrum (SS) communication scheme which combined with orthogonal SS and CPSK technique is proposed. Based on dual orthogonal SS, every SS code is treated as original code to adopt CPSK modulation, the unattached synchronous code is chosen to achieve system synchronization. At the receiver, A circular correlator based on transform domain processing is employed to de-spread the received signals. Compared with M-ary SS and CPSK, the proposed scheme is able to obtain higher bandwidth efficiency, stronger anti-intercept capability, and better synchronous performance. The Monte-Carlo simulation results demonstrate that the proposed scheme can achieve better synchronous and bit error rate (BER) performance under additional white gauss noise channel models.

Abstract: To prevent medical errors or even accidents, our solution is to design the closed-loop application based on Radio Frequency Identification (RFID) technology in the Hospital Information System (HIS). We focus on the information improvement for doctor's order based on RFID. The whole closed-loop process starts from the initial collection of the patient's information, through confirmation of the unique identification of the patient, and to the finishing of the doctor's order at last. The final information is written back into HIS. Medical staff can collect and deal with the patient's information straightly through the system, thereby guarantee maximal medical information correctness. The system design of the closed-loop process of the doctors order includes new workflow and its wireless system architecture based on RFID in the ward environment.

Abstract: Hybrid free space optical/radio frequency communication systems improve reliability of links. However, independent communication subsystems increase the system complexity, weight, size, and power consumption. Based on microwave photonics, a unified hybrid free space optical/radio frequency communication system design is proposed. The communication subsystems share antenna, modulator, and demodulator to simplify system structure. Operating principle is expounded by theoretical reference, and 3dB theoretical loss is found in millimeter-wave communication mode.

Abstract: Its based on the voice value-added business booming and combined with the value-added service of mobile and network so that the fixed telephone intelligent voice service system is put forward in the paper. The system is constituted with voice rafting business and fixed telephone business like we chat, which is constructed by voice acquisition, number identification, voice feedback and customer information processing module. The rafting business is devoted to solve the difficulty that the users have communication impediment in different time domain. And the business is used availably for work and amusement through orientation conveying or not. The applied range of we chat is broadened because of the fixed telephone business like we chat. The fixed telephone business like we chat is realized by the store-and-forward way to achieve the communication with real time and different time domain. The birth of the new business model will bring consumers the different experience and feelings. The general control scheme, general structure, software modules, business content and running process are included in the paper of the detailed content, and then make the analysis of the dominance of the IVSS (Intelligent Voice Service System).

Abstract: To deal with the demodulation problem of rolling bearing defect vibration signal in heavy noise, a new method based on time-delayed correlation algorithm and ensemble empirical mode decomposition (EEMD) is presented. Introduced the time-delayed autocorrelation de-noising principle. After the discretization and unbiased estimation of the original signals autocorrelation function , de-noising pretreatment is implemented by appending a rectangle window. Then an envelope signal can be obtained by the first Hilbert transform. After the EEMD decomposition, some interested intrinsic mode functions (IMFs) can be collected. By making the second Hilbert transform of the IMFs, we can get the local Hilbert marginal spectrum from which the defects in a rolling bearing can be identified. By repeated analysis of simulation signals and actual rolling bearings defect vibration signal, the results show that the proposed method is more effective than direct modulation or only time-delayed correlation demodulation or combine time-delayed correlation with EMD demodulation in de-noising and diagnosing the rolling bearing's defect information.