Hsien-Wei Tseng

The Measurement and Analysis of WiMAX Base Station Signal Coverage

This paper presents the fleld trial measurement data of WiMAX base station; it includes the system coverage, signal strength and available transmission rate. Data consisting of real time images, VoIP internet telephone are transmitted through Skype software by using WiMAX, HSDPA (3.5G) and EDGE (2G) transmission techniques, and these data are connected to centrally equipped wireless monitoring servers to perform data monitoring and analysis. Finally, we make comparisons, analysis and discussions of these three transmission techniques from the measured and characterized data.

Using Genetic Algorithm with frequency hopping in device to device communication (D2DC) interference mitigation

Device-to-device communication (D2DC) is an important and challenge technique in the next generation of wireless communication that it can effectively reduce the load of base stations and simultaneously allows user equipment (UE) to proceed in direct communications. In D2DC, devices are very close among themselves and therefore the resulting interferences maybe quite serious, it becomes an important issue of how to properly select a UE owner so that when this UE owner searches for its associated communicating UEs in its service range they will suffer the least interference effect. In this paper, as UEs are distributed and clusters of UEs are formed in the D2D communication area; we propose to use K-Means to locating a UE around the cluster center as the UE Owner of the cluster. With this formation of UE clusters and UE owners they still have the chance to incur interferences among UE clusters due to they may be possibly use the same frequency band in their communications. Frequency hopping technique is then considered in this paper to further reduce the co-channel interference. In this paper it proposes to use Genetic Algorithm (GA) with frequency hopping technique to optimally select the number of frequency channels required in the system and then allocate these frequency channels to the UE clusters for their D2D communications. Simulations have been performed in a D2DC system with the proposed GA algorithm to reveal the effectiveness of the designed algorithm in the allocation of frequency channels to the clusters with minimum interference effect.

Design and implementation of subchannelization scheduler in IEEE 802.16 broadband wireless access systems

Abstract In this paper we propose a method of using a heuristic Genetic Algorithm (GA) to solve the Fast Fourier Transform subchannelization scheduling (FFTSS) problem in IEEE 802.16 broadband wireless access systems. In such a multi‐user transmission system with quality of service (QoS) requirements, data from different users should be quickly scheduled and transmitted within the shortest transmission time period. In this paper, we propose a GA‐based scheduler that will search the best configurations of the uplink and/or downlink sub‐frames in order to obtain the optimal system throughput as well as quality of services. Due to the slow convergence of conventional GAs, we design a novel hardware architecture to accelerate the processing speed of GA which is used for scheduling the Down Link (DL) sub‐frames. We then describe the procedure of using Field‐Programmable Gate‐Array (FPGA) to implement the designed hardware to verify the convergence of the algorithm. With this hardware implementation, the proposed method indeed helps us to construct a fast optimization tool to be applied in broadband wireless communication systems.

Applying Genetic Algorithms to the Data Traffic Scheduling and Performance Analysis of a Long-Term Evolution System

In this study it develops a superior transmission resource allocation method by using genetic algorithm. The convergence properties of genetic algorithm are employed to increase the transmission resource use efficiency of a base (station) to allow users to access wider bandwidth and to improve the system throughput and packet service rate. In this paper, it also studies the genetic algorithm convergent phenomena. The calculated system convergent time is significantly less than that of a long term evolution (LTE) frame duration. Finally, the system performances with and without implementing the genetic algorithm in resource allocations are simulated; their performances are compared to study the effectiveness of using the genetic algorithm in resource allocation.

ANALYSIS OF SYSTEM PERFORMANCE FOR AN OPTICAL CDMA SYSTEM IMPLEMENTED WITH SYNCHRONOUS RECEIVER

Abstract In this paper, we study and analyze the system performance of an optical code‐division multiplex access (CDMA) system implemented with synchronous receiver. In the traditional optical CDMA access system, optical signals emitted from users are transmitted at the same power level. When these signals arrive at the receiver terminal, due to different distances traveled for each signal from the transmitter to the receiver, they will be at different power levels. In this paper we propose a mechanism to estimate first the distance between a transmitter and a receiver and then from this distance information to estimate its associated time delay so as to shift the signal time frame structure and adjust its transmitting power level so that a synchronous receiving system is generated. Using the VPItransmissionMaker software the system performance of the proposed system is simulated, and the results show that the proposed synchronous receiving system gives better performance than a traditional synchronous transmitting system.

A Hybrid System with Petri Net and Fuzzy Theory

In this paper, we issue a hybrid system, which is integrated with the fuzzy system and Petri net models. We exploit the characteristics, imprecise or ambiguous information, of fuzzy theory to map the algorithm of crisp inputs and outputs, furthermore, model problems, product a nonlinear function, and final predict the next state transition of Petri net graphs. In order to quickly and precisely predict the result state, we use the Center of Area (COA) defuzzification method to infer the state transition for this hybrid system. Finally, we issue an example of washed-machine to illustrate this proposed hybrid system.

A method of measuring sleep quality by using PPG

Modern life is more busy than previous, after a busy day of work, sleep quality at night has become an important part of the next day that can working smoothly. With the development of wearable devices, people must go to the medical center to spend a whole day for sleep diagnosis in the past day, but now they have opportunity achieve a simple sleep quality measurement by using wearable devices.

A method of measurement sleep quality by using EEG

Due to the pressure of modern life and work, resulting in poor quality of sleep, insomnia and other issues, in order to find suitable for daily life can get sleep quality approach to further analysis to improve sleep quality. This paper contained a Bluetooth device through a single conductive layer measured by EEG brainwave of slow-wave signals to judge the quality of sleep during sleep. This paper use wearable module DAQ100 to measure the sleep cycle α, β, θ, δ four single conductive layer, and transmit this date to the cloud to do data analysis by Bluetooth device, to improve the sleep quality.

2.4-GHz (ZigBee) Indoor Intrusion Detection

In this era of the Internet of Things, many studies have proposed and implemented smart home technologies. This paper proposes a technique that involves using link quality index level variations among end devices to detect intrusion and an algorithm for estimating the possible intruder location. The IEEE 802.15.4 ZigBee technique was adopted as the platform for the wireless sensing technology used.

Eliminating motion artifacts in PPG

In this study, independent component analysis was employed to separate the independent components (i.e., PPG signals and noise) from the raw signals with motion artifacts. Subsequently, independent components containing PPG signals were selected and the locations of the PPG signal components on the frequency spectrum were analyzed. Next, the raw signals passed through a multi-bandpass filter specifically designed for this study to eliminate motion artifacts. For the experiment, motion artifacts were created using four types of finger movements: vertical finger movement, horizontal finger movement, rapid finger shaking, and random finger shaking. The study results included an independent component analysis of the independent components, the waveforms of the filtered PPG signals in the time and frequency domains, and the heart rate measurements.