Paper Title, Authors, Abstract (Issue 1, Volume 1, 2007)

Pages

QCIF Images Performance Analysis Over Adaptive Modem
Mohamed Fourati, Lamia Chaari, Nouri Masmoudi, Lotfi Kamoun

Abstract: This article proposes, modulation study with multi-levels QoS analysis, which can be used to perform physical layer functions for new generation systems. The 3G wireless systems, the wireless LANs, and the wireless MAN have included different modulation schemes as a means to provide a higher data rate. Based on the perceived Signal-to-Noise Ratio (SNR) of the immediately previous frame in the frame exchange process, provisioning of service delivery are dynamically varied by selecting links that can use higher bandwidth modulation schemes. In this paper, we considered different images classes and different modems schemes to provide a study of the physical-layer link speed effect on high-layer network performance based on different QoS parameters that depend in class and type of multimedia traffic. In our work, we have considered basics modulation techniques used in mobile and wireless systems. Based on this analysis an adaptive modulation scheme for SDR is proposed to pick the constellation size that offers the best reconstructed image quality for each average SNR. Simulation results of image transmissions confirm the effectiveness of our proposed adaptive modulation scheme.
 

Intra/inter algorithm for B frame processing in H.264/AVC encoder
Zoran M. Milicevic and Zoran S. Bojkovic

Abstract: The H.264/AVC video coding standard aims to enable significantly improved compression performance compared to all existing video coding standards. In order to achieve this, a robust rate-distortion optimization (RDO) technique is employed to select best coding mode. This paper presents combined (intra and inter prediction) fast mode decision algorithm for H.264/AVC. The objective is to reduce the computational complexity of the encoder without significant rate-distortion performance degradation. The choose method reduces the computational time savings for B picture up to 42 %, when using modification H.264/AVC encoder with negligible loss of rate-distortion performance.

    Paper Title, Authors, Abstract (Issue 2, Volume 1, 2007)

Pages

Graham?s anomalies in case of parallel computation electromagnetic phenomena
J. Ko?ota, J. Smykowski, and S. St?pie?

Abstract: Parallel computing becomes common tool to accelerate long-lasting electromagnetic computations. In some cases their realization does not bring an expecting gain. In this paper the authors present the results of the simulations from application created in order to show selected anomalies in parallel computing. The way of parallel system implementation is presented on the basic of direct graph model with the set of precedence constraints. The Graham?s anomalies are discussed during optimization tasks scheduling issue, towards makespan criterion. The research was focused on three most frequently applied cases during acceleration the computations i.e. shortened tasks times execution, add additional computational power and reduction of selected precedence constraints. All phenomena are discussed and presented with the usage of Gantt?s charts.
 

Estimating resource requirements for distributed Network Management applications in mobile
Filippo Neri

Abstract: he current centralized Network Management approach in mobile networks may lead to problems with being able to scale up when new customer services and network nodes will be deployed in the network. This consideration has prompted a research activity to find alternative application architectures that could overcome the limits of the current centralized approaches. In this paper, we describe the PIRR methodology we have developed to measure resource requirements for distributed applications in mobile networks and the experimental findings of its application to new Network Management applications.he current centralized Network Management approach in mobile networks may lead to problems with being able to scale up when new customer services and network nodes will be deployed in the network. This consideration has prompted a research activity to find alternative application architectures that could overcome the limits of the current centralized approaches. In this paper, we describe the PIRR methodology we have developed to measure resource requirements for distributed applications in mobile networks and the experimental findings of its application to new Network Management applications.
 

Adaptive Radio Resource Management in Heterogeneous Wireless Networks
Yao-TienWang and Chung-MingOu

Abstract: In this paper, adaptive channel management approach fuzzy neural networks in heterogeneous wireless networks (ACM-FNN) is presented to efficient resource allocation, and admission control schemes are needed to guarantee quality-of-service (QoS) for differentiated services. The channel management in a two-tier such as micro cell or macro cell wireless networks. Effective reliability and efficiently schemes are also needed to make network services more reliable and efficient. In a wireless networks for uneven traffic load may occur creating a hot spots. So the two-tier wireless cellular system should be able to cope with such traffic load in certain cells. To keep the handoff calls in a two-tier wireless networks at an acceptable level with low mobility users should undergo handoff calls at micro cell boundaries, and hight mobility users should undergo hand off calls at macro cell. In wireless network, the calls arrival rate, the call duration , the mobility speed and the communication overhead between the base station and the mobile switch center are vague and uncertain. Therefore, we propose a new efficient channel allocation scheme in heterogeneous wureless networks based on ACM-FNN. The proposed scheme exhibits better learning abilities, optimization abilities, robustness, and fault-tolerant capability thus yielding better performance compared with other algorithms. The results show that our algorithm has lower new calls blocking rate, lower call handoff calls dropping rate, less update messages overhead, and shorter channel acquisition delays.
 

Computationally Efficient Analytical Crosstalk Noise Model in RC Interconnects
P.Chandrasekhar and Rameshwar Rao

Abstract: This paper presents an accurate, fast and simple closed form solution to estimate crosstalk noise between two adjacent wires, using RC interconnect model in two situations: simple resistance as driver and short channel CMOS inverter as a driver. The salient features of our proposed models include minimization of computational overhead, elimination of adjustment step to predict the peak amplitude and pulse width of the noise waveform. Numerical calculations are compared with SPICE simulation and other metrics by plotting the noise voltage verses time. Based on our proposed models, we derive analytical delay models due to RC interconnect in each case. Finally we formulate energy dissipation of the RC coupled interconnects in both the cases using our proposed metrics. Experimental results indicate that our models are closely comparable with SPICE simulation, with an average estimation error of 3.366%.
 

Cooperative System for 4G Wireless Communication Networks
Ying-Hong Wang, Hui-Min Huang and Chin-Yung Yu

Abstract: Various services supports are the principal requirements of the Fourth Generation (4G) system; therefore, the need to improve integration of heterogeneous networks is significant. This paper amends EVOLUTE (a project of Information Society Technologies (IST)) to strengthen mobility management. This paper uses Multicast-based Mobility (M&M) to aid Cellular IP (CIP) in micro-mobility management. The aim of this paper is to produce complete integration of heterogeneous networks to support fine-fit mobility management for seamless handoff. The cooperative M&M/CIP is suitable for macro-mobility management, proposed by EVOLUTE, to support real-time and non-real-time data flow in micro-mobility management. Simulation results prove that the proposed system achieves good performance than other existed methods.
 

Human exposure assessment in the vicinity of 900 MHz GSM base station antenna
Mimoza Ibrani ? Pllana, Luan Ahma, Enver Hamiti

Abstract: Daily exposure to GSM electromagnetic fields has raised public concern of possible adverse health effects to people living in the vicinity of base station antennas. International guidelines and standards established for limiting human exposure to electromagnetic fields are given in two categories: Basic restrictions (SAR, induced current density and induced power density) and Reference levels (free space electric field intensity, magnetic field intensity and power density). In order to check compliance for both categories, in this paper are presented measurements of incident electric field and obtained results are used for numerical prediction of SAR. Measurements of field strength and power flux density are performed on locations few meters away from base station antenna, in different levels, with and without usage of mobile phones, during day and in peak hours of GSM system usage. Results are compared with ICNIPR Guidelines, IEEE and CENELEC standards
 

Embedding wireless sensors in UPnP services networks
Radu Dobrescu, Matei Dobrescu, Maximilian Nicolae and Dan Popescu

Abstract: The goal of the equipment which is proposed for research and developed in an experimental version is to associate a typical WSN (wireless sensor networks) node architecture with the UPnP services architecture, in order use TCP/IP and WEB technologies to manage sensor networks without a specific configuration. The sensor management software architecture uses UPnP and WSN technologies and allows interactions between UPnP Control Points and wireless sensors networked in the ambient environment. Even if the sensor devices are embedded systems with limited resources, the proposed software package allows direct interactions with UPnP services.
 

A method of improving SCR for millimeter wave FM-CW radar without knowledge of target and clutter statistics
Fumio Nishiyama, and Hideo Murakami

Abstract: Frequency-modulated-continuous-wave (FM-CW) radars transmit a waveform whose frequency changes linearly in time. Received echoes of these radars can be categorized into two types due to either targets or clutter. Generally, the received target signals have a stronger correlation with respect to different carrier frequencies than that of the received clutter signals. This paper discusses a method of improving signal-to-clutter ratio (SCR) for millimeter wave FM-CW radar based on this statistical difference between the target and the clutter. The method first approximates an autocorrelation function from received signals using a numerical averaging. A power spectrum of received signals is obtained by taking discrete Fourier-transform of this autocorrelation. A target power spectrum is estimated from the power spectrum of received signals exploiting the statistical difference, and a matched filter is then designed from this target power spectrum. The matched filter is used to improve SCR. Performance of the method is analyzed and evaluated experimentally for 60GHz band FM-CW radar. The simulation shows that the proposed method improves SCR better than competing with other methods.
 

    Paper Title, Authors, Abstract (Issue 3, Volume 1, 2007)

Pages

A Harmonical Model for Approximating the Identity in Min-Plus Convolution
Ming Li and Wei Zhao

Abstract: Min-plus convolution is an algebra system that has applications to computer networks. Mathematically, the identity of min-plus convolution plays a key role in theory. On the other hand, the mathematical representation of the identity, which is computable with digital computers, is essential for further developing min-plus convolution (e.g., de-convolution) in practice. However, the identical element in min-plus convolution is defined as infinity over infinite interval, making digital computation of the identity difficult because digital computers only provide finite range of numbers for numerical computations. Consequently, the issue of numerical approximation of the identical element is worth discussing. This paper proposes a harmonic model for finite approximation of the identical element in the min-plus convolution.
 

A Note on Statistically Detecting Tampered Type Attacks
Ming Li and Wei Zhao

Abstract: Information integrity of communication data is crucial to e-business systems. An adversary may delete or insert packets into a normal communication data series in e-business systems to destroy information integrity to produce deserters (likely informal, this paper uses the term tamped type attacks to specifically describe those that attackers detect or insert packets into a normal data series). Consequently, a security issue in an e-business system is how to detect tamped type attacks. From a view of intrusion detection systems, statistic methods of intrusion detection are increasingly paid attention to [1-3]. This short paper gives a method for statistically real-time detection of tampered type attacks. The method is based on power spectra of monitored traffic time series with finite length. The detection probability is derived. A case study is demonstrated with a real-traffic series to suggest that the present method can be used to give an alarm at the early stage of intrusions.
 

VHDL Modeling of the CSMA/CA
W.L. Pang, K. W. Chew, Florence Choong, E.S. Teoh

Abstract: The wireless communication is highly deployed due to it convenience of mobility. The wireless local area network, WLAN is dominated by IEEE802.11 standard. All the new notebooks are equipped with the IEEE802.11 b WLAN. It becomes one of the main focuses of the WLAN research. Most of the researches are simulation based due to high cost required for the hardware implementation. The IEEE802.11b standard contains two major operations, the Distribution Coordination Function (DCF) and Point Coordination Function (PCF). The main core of the IEEE802.11b, the CSMA/CA and the IEEE802.11b Physical and MAC are modeled in this paper using VHDL. The VHDL is defined in IEEE as a tool of creation of electronics system because it supports the development, verification, synthesis and testing of hardware design, the communication of hardware design data and the maintenance, modification and procurement of hardware[2]. The CSMA/CA is modeled to 3 major blocks in VHDL, the CSMACA, Random Generator and counter. The CSMA/CA is successfully modeled with a total of 58 pins and it used 15% of the total logic elements of the APEXTM 20KE FPGA. The CSMA/CA can support the operation frequency up to 50MHz.
 

FPGA Realization of Open/Short Test on IC
W.L. Pang, K. W. Chew, Florence Choong, C.L. Tan

Abstract: IC (Integrated Circuitry) testing requires the very advanced and sophisticated Advance Test Equipment (ATE) that costs multi million USD. The cost of IC testing is increasing yearly and it will exceed the cost of manufacturing in future. The manufacturers are interested to lower down the manufacturing cost. Low cost tester is one of the options to reduce the manufacturing cost. The low cost FPGA realization of Open/Short Test on IC is introduced to reduce the IC test cost. The open short test is selected, because it is the first IC test. The Very High Speed Integrated Circuit Hardware Description Language (VHDL) is used to model the Open/Short Test on IC and the design is capable to perform the open/short test.
 

Scrutinizing Behavior of a Dynamic Framed Slotted Anti-collision Algorithm for RFID Systems
Xu Huang

Abstract: Radio frequency identification systems with passive tags dramatically increase the ability of an organization to acquire a vast array of data about the location and properties of any entity that can be physically tagged and wirelessly scanned within certain technical limitations. However, if multiple tags are to be identified simultaneously, messages from the tags can collide and cancel each other out. One of the popular anticollision algorithms is the ALOHA-type algorithm, which is simple and has good performance when the number of tags to be read is reasonable small. In this paper we extended our previous research [8, 17] to build a more efficient dynamic framed slotted ALOHA for passive tags in RFID systems under the condition titled ?maximum efficiency? [8]. Also the behavior of the ALOHA for RFID passive tags is investigated, which facilitates the future relevant research projects.
 

A Method of Improving SCR for Millimeter Wave FM-CW Radar Without Knowledge of Target and Clutter Statistics
Fumio Nishiyama and Hideo Murakami

Abstract: Frequency-modulated-continuous-wave (FM-CW) radars transmit a waveform whose frequency changes linearly in time. Received echoes of these radars can be categorized into two types due to either targets or clutter. Generally, the received target signals have a stronger correlation with respect to different carrier frequencies than that of the received clutter signals. This paper discusses a method of improving signal-to-clutter ratio (SCR) for millimeter wave FM-CW radar based on this statistical difference between the target and the clutter. The method first approximates an autocorrelation function from received signals using a numerical averaging. A power spectrum of received signals is obtained by taking discrete Fourier-transform of this autocorrelation. A target power spectrum is estimated from the power spectrum of received signals exploiting the statistical difference, and a matched filter is then designed from this target power spectrum. The matched filter is used to improve SCR. Performance of the method is analyzed and evaluated experimentally for 60GHz band FM-CW radar. The simulation shows that the proposed method improves SCR better than competing with other methods.
 

FPGA Implementation of RSA Encryption Engine with Flexible Key Size
Muhammad I. Ibrahimy, Mamun B.I. Reaz, Khandaker Asaduzzaman and Sazzad Hussain

Abstract: An approach to develop the FPGA of a flexible key RSA encryption engine that can be used as a standard device in the secured communication system is presented. The VHDL modeling of this RSA encryption engine has the unique characteristics of supporting multiple key sizes, thus can easily be fit into the systems that require different levels of security. A simple nested loop addition and subtraction have been used in order to implement the RSA operation. This has made the processing time faster and used comparatively smaller amount of space in the FPGA. The hardware design is targeted on Altera STRATIX II device and determined that the flexible key RSA encryption engine can be best suited in the device named EP2S30F484C3. The RSA encryption implementation has made use of 13,779 units of logic elements and achieved a clock frequency of 17.77MHz. It has been verified that this RSA encryption engine can perform 32-bit, 256-bit and 1024-bit encryption operation in less than 41.585us, 531.515us and 790.61us respectively.
 

Adaptive Quantization of Wavelet Packet Coefficients for Embedding and Extraction of Digital Watermarks
Chi-Man Pun and I-Kuan Kong

Abstract: In this paper, a robust digital image watermarking approach of embedding and extraction of digital watermarks using adaptive quantization of wavelet packet coefficients was proposed. The original image is decomposed by discrete wavelet packet transform and the dominant wavelet coefficients are selected for watermark embedding from each sub-band except the lowest frequency one. Then, each watermark bit is adaptively embedded with different strength into the selected wavelet packet coefficients based on the odd or even value after quantization. Experimental results show that the proposed method is effective for copyright verification and robust to various common attacks such as Gaussian noise, JPEG compression, and without original image as references.
 

UCAIPM: Ubiquitous Computing Agile Information Protection Mechanism
Daoqing Sun and Qiying Cao

Abstract: In order to improve the security of ubiquitous computing system, UCAIPM, a new novel ubiquitous computing agile information protection mechanism is presented. The protected information includes the identity, location, activity of the entities and their neighbors, the service resource like the currently available devices, the schedule like the developing history of the entities and their neighbors. The SPKI-based authorization technology is used in the mechanism to solve the identification validation, security communication and the security level division. The D-S Evidence Theory is used to compute the trust value for deciding the trust level from the service provider to the ingoing user.
 

Cipher Text to Be Transmitted and Cryptanalysis in Network Security
Tsang-Yean Lee, Huey-Ming Lee, and Nai-Wen Kuo

Abstract: In this paper, we propose an encryption algorithm to encrypt plaintext to cipher text. We divide plaintext into numeric and non-numeric fields, also, we pack the numeric fields to produce packed numeric table and combine it with symbol fields to produce the new plaintext. We apply the basic computing operations, e.g., inserting dummy symbols, rotating, transposition, shifting and complement, in the proposed algorithm to encrypt plaintext to cipher text. The produced the cipher text which contains the plaintext, relative data and tables of encryption is transmitted to the receiver through the network. We also propose the cryptanalysis about these algorithms. It can be shown that the proposed algorithm is more secure in network security.
 

Cavity Dynamics of a Figure of Eight Fiber laser
Zheng Zheng, Muddassir Iqbal, Tian Yu

Abstract: Pulse propagation in a birefringent medium carries due weightage and importance in passive modelocking of fiber lasers. We carried out study of nonlinear effects in birefringent medium by simulating pulse propagation using adaptive step size method, which is globally an efficient algorithm for solving Schrodinger type equations using split step Fourier method. Nonlinear optical loop mirror was realized; the results hereby are used in forming a figure of eight fiber laser using NOLM.
 

Cavity Dynamics of an Actively Modelocked Fiber Ring Laser
Muddassir Iqbal, Zheng Zheng

Abstract: With growing demand of bandwidth, modelocked fiber lasers are mandatory for having smooth and efficient communication systems. We have simulated and analyzed the cavity dynamics of an actively modelocked fiber ring laser for Gaussian pulse as well as under soliton conditions. In order to do full justification with nonlinear as well as dispersive effects, we have optimized the algorithm using a previously explored approach. We had explored nonlinear phenomena in various type of fibers using the said approach. Results are compared with conventional method and found in coherence. Novelty lies in optimization of algorithm in order to get precise and accurate results.
 

Research of the ARP Spoofing Principle and a Defensive Algorithm
Yang Liu, Kaikun Dong, Lan Dong, Bin Li

Abstract: During the network communication process, attacker carry on ARP spoofing by using the disadvantage of the ARP(Address Resolution Protocol) protocol, this phenomenon is seriously threaten the LAN security. This paper will introduce the commonly used ARP spoofing methods such as internal/external network sniffing, interception, malicious attack and so on. It presents the Matching IP method, Data monitor method, Echo time method, ARP response analysis method, software tools detecting method as well as the new method of ARP cache updating, using switching equipment to control and other strategy and presents the algorithm to keep ARP spoofing away and maintain network security.
 

Glasses for ion-exchange technology
F. Rehouma and K. E. Aiadi

Abstract: Integrated ion exchanged devices on glass seems to be as one of the most promising technologies for the development of optoelectronic field. That is due to the potentiality of glass material, facility and flexibility of the fabrication process, the cost of the elaborated devices and the high performances of these components. In this paper, a review on glasses used for ion exchanged structures is given. The structure and the influence of the composition on the glass properties are presented. The ion exchange technology is described. The relation between the glass compositions and the exchanged ions is treated. Some compositions of glasses suited to this technology and the characteristics of elaborated structures are given. Finally selection criteria of glasses adapted to this technology are proposed.
 

    Paper Title, Authors, Abstract (Issue 4, Volume 1, 2007)

Pages

An Effective Routing Algorithm for Real-Time Applications
Hazem M. El-Bakry, Nikos Mastorakis

Abstract: It is highly desirable to protect data traffic from unexpected changes as well as provide effective network utilization in the internetworking era. In this paper the QoS management issue that utilizing the active network technology is discussed. Such algorithm is based on the proposed work presented in [15]. Active networks seem to be particularly useful in the context of QoS support. The Active QoS Routing (AQR) algorithm which is based on On-demand routing is implemented incorporating the product of available bit rate and delay for finding the best path for dynamic networks using the active network test bed ANTS. It is inferred that with background traffic, the AQR finds alternative paths very quickly and the delay and subsequently the jitter involved are reduced significantly. In this paper the variant of AQR implemented is demonstrated to be more useful in reducing the jitter when the overall traffic in the network is heavy and has useful application in finding effective QoS routing in ad-hoc networks as well as defending DDoS attacks by identifying the attack traffic path using QoS regulations. The main achievement of this paper is the fast attack detection algorithm. Such algorithm based on performing cross correlation in the frequency domain between data traffic and the input weights of fast time delay neural networks (FTDNNs). It is proved mathematically and practically that the number of computation steps required for the presented FTDNNs is less than that needed by conventional time delay neural networks (CTDNNs). Simulation results using MATLAB confirm the theoretical computations.
 

Markovian Chain Analysis in ALOHA for Satellite Applications
Mario Reyes-Ayala, Edgar Alejandro Andrade-Gonzalez, Jose Alfredo Tirado-Mendez and Hildeberto Jardon Aguilar

Abstract: In this paper, the average delay in ALOHA is calculated for digital satellite system. The main parameters to analyze the system are the throughput, the average number of retransmission and the average packet delay. A complete mathematical analysis is presented where a Markov Chain is used.
 

OFDMA in High-speed Mobile Systems, Pilots and Simulation Problems
Miriam Bank, Michael Bank, Motti Haridim, Boris Hill

Abstract: A proposal is put forward for an innovative method of multiple access, termed Frequency Bank Signal (FBS). The major advantage of FBS is that the error probability is almost non-sensitive to, either, the Doppler Effect, separate signal delay or to the negative effect of reflected signals. In addition, FBS signals do not require special pilots or equalization signals. Two methods, based on Frequency stuffing and time stuffing, for simulation of OFDMA systems are proposed. Both methods are characterized by enhance resolution and allow for monitoring of the influence of impairments such as orthogonality disturbance, non-ideal synchronization and jitter in the receiver.