Switching Center Research Articles

Performance Analysis of High Data Rate Wavelength Division Multiplexed Passive Optical Networks (WDM-PON) for Mobile Backhaul Application

AbstractIn this work, we propose a sixteen channel wavelength division multiplexed passive optical network (WDM-PON) architecture which provides seamless connectivity between mobile switching center (MSC) and base transceiver stations (BTS) and also serves the fiber to the home (FTTH) users. WDM-PON based mobile backhaul network is considered to be a prime solution due to its quick deployment and reduced cost. Due to growing demand for connectivity and data transmission, the number of wavelengths are increasing day by day. The bit error rate (BER) performance is analyzed for the discrete data rates per wavelength (viz. 2.5 Gbps, 5 Gbps, 10 Gbps, 20 Gbps, and 40 Gbps) at discrete reach for 16 channel WDM-PON. The optical spectrum of sixteen channel WDM-PON is observed for different data rates at multiplexer output and the same is analyzed after fiber distance of 20 km. The fiber reach of the WDM-PON is varied, and its effect on the performance parameter like bit error rate (BER) and Quality Factor (Q-Factor) is observed on BER analyzer for the discrete data rates per wavelength. It is found that as data rate per wavelength increases, the error-free reach of the WDM-PON system decreases. Proposed WDM-PON architecture performs superior to the compared work under similar initial conditions.

Artificial immune system (AIS)-based location management scheme in mobile cellular networks

In this paper, we are proposing a bio-inspired location management (LM) technique for personal communication system (PSC). It is based on artificial immune system (AIS), with self-adaptation and self-update attributes to perform the location management, and helps to achieve better quality of service (QoS) and quality of experience (QoE) for the mobile users. Here, we are suggesting a modified mobile switching center (MSC) architecture, and an adaptive self-modified location management procedure. The proposed mobile switching center architecture has an advantage of rule-based and fact-based system to store the rules and facts related to location management procedure, and it shows the intelligent behavior of system. The mobile switching center calculates the best method for location management and the rule-based system trigged the rules to perform the techniques. The system stores the result (techniques for location management) in fact-based system for future use. The efficiency and effectiveness of the proposed techniques have been analyzed, and it observed that the proposed system has 45–50% improvement in performance over the current location management techniques. Here, we are using performance parameters such as signaling cost, database update cost, overhead measurement, and mobility management cost.

Recirculating Buffer and Arrayed Waveguide Grating-Based Switch for Optical Data Centers

Abstract Recently, an explosive growth has been observed in data traffic, which restricts the speed of exiting data communication network. To solve such problem, fiber optical-based optical communication is preferred choice. In this paper, a switch design is proposed to tackle contention problem in Optical Packet Switching (OPS) and data center networks. The proposed switch is compared with recently proposed switch design and advantages of proposed design are presented. To show superiority of the proposed design over earlier one, mathematical modeling is presented and expressions for noise figures and Bit Error Rate (BER) are derived. Using the mathematical framework, switch analysis is done in terms of BER and packet loss probability, and it has been found that power required for correct operation of the switch is lesser in comparison to earlier one. The effect of recirculation count on packet loss probability is detailed. The network layer analysis in terms of packet loss probability is also done using Monte Carlo simulation, and relation between physical and network layer parameters is also discussed.

A new green energy interface for telecommunications

ABSTRACTProviding electricity to telecom tower can be realised by hybrid green energy systems than extending a power line from grid. For a hybrid energy system, it is important to develop a converter to integrate different power sources and storage elements. Conventional systems use an individual converter for individual source thus leading to a relatively complex configuration, larger component count and reduced system efficiency. To address these issues green energy interface (GEI) converter is used. In this paper, a detailed component wise analysis and performance comparison between conventional and GEI converter using Matlab/Simulink is presented. GEI converter has linear and non-linear components. So, small signal model based on state space averaged model of the GEI topology is obtained. A lab level prototype for the GEI converter with programmable interface controller is implemented and tested under various input conditions to study the performance of the converter during seasonal changes. The simulation and experimental results showed that effective operation and control strategy of the hybrid power supply system.Abbreviations: BTS: base transceiver station; MSC: mobile switching centre; BSC: base station controller; CAPEX: capital expenditure; OPEX: operational expenditure; GEI: green energy interface

Method of optimum channel switching in equipment of infocommunication network in conditions of cyber attacks to their telecommunication infrastructure.

On the basis of the mathematical graph theory, the method of optimum switching of infocommunication networks in the conditions of cyber attacks is developed. The idea of representation of a set of possible ways on the graph in the form of the multilevel tree ordered by rules of algebra of a logic theory is the cornerstone of a method. As a criterion of optimization, the maximum of network transmission capacity to which assessment Ford- Falkerson's theorem is applied is used. The method is realized in the form of a numerical algorithm, which can be used not only for design, but also for operational management of infocommunication networks in conditions of violation of the functioning of their switching centers.

On spatially disjoint lightpaths in optical networks

The core network in the information communication technology infrastructure is based on the optical fiber technology. The core network is of prime importance because it connects all the central offices in the wired communication networks and the mobile switching centers in the wireless communication networks. The optical link between two network nodes is a lightpath, which offers very high speed, low loss, lower cost, highly reliable, secure and very high capacity, end-to-end communication over a very long distance. Any damage to a lightpath in the event of a disaster may lead to massive service interruptions and financial losses for the network operators. Therefore, survivable routing in these networks is very important. Generally, the survivability is ensured by having a backup lightpath to keep communication intact because the primary and the backup light paths are always disjoint. However, they may still fail simultaneously in the event of a large-scale disaster, if their separation distance in the physical plane is small. Hence, the spatial distance between the disjoint lightpaths should also be taken into consideration when establishing the lightpaths. Our contributions in this paper are twofold: (1) a routing algorithm is proposed for provisioning a pair of link-disjoint lightpaths between two network nodes such that their minimum spatial distance (while disregarding safe regions) is maximized, and (2) another routing algorithm is proposed for provisioning a pair of link-disjoint lightpaths such that the path weight of the primary lightpath is minimized, subject to the constraint that the backup lightpath has some particular geographical distance from the primary lightpath. Through extensive simulations, we show that our first algorithm can provide maximum survivability against spatial-based simultaneous link failures (due to the maximized spatial distance), whereas the second algorithm can tune the spatial distance between the lightpaths keeping in view the target survivability requirements and the path weight for the primary lightpath.

QUEUEING MODEL FOR SOFT HANDOFF ANALYSIS IN CDMA BASED WIRELESS CELLULAR NETWORK

The most important feature of the mobile network is mobility. Good and continuous service in cellular mobile network can be achieved by using the procedure of handoff (or handover) from one cell to another. Soft handoff is very important feature of cellular Code Division Multiple Access (CDMA) system. In CDMA system a mobile stations (MSs) within a soft handoff region use multiple radio channels and receive their signals from multiple base stations simultaneously. In CDMA cellular system, all cells can also share the same frequency. During handoff procedure, the signaling and voice information from multiple base stations are combined at the mobile switching center (MSC). During the handoff procedure, voice and signaling information must be sent to multiple base stations and the mobile station must combine the results. Within the overlapping area (which is developed by the adjacent cells) of cells, a handset can connect to multiple base stations. In this research paper, a new soft handoff scheme for CDMA cellular network is proposed and investigated. Here we introduce the concept of overlap region between adjacent cells and develop an analytical model for soft handoff in CDMA system. In developed soft handoff model, the balking and reneging behaviors of handoff calls have also considered. Different performance measures of the soft handoff model have developed.

Minimising network cost by employing sliding window method at mobile switching centres in GSM network

The cost effort of a global system for mobile communications (GSM) network is to be minimised for meeting effectively and efficiently the service requirements of ever increasing mobile subscriber's base. The period of temporary storage of subscribers' profiles in visitor location register (VLR) at a mobile switching centre (MSC) affects the cost of GSM network. This research study proposes a sliding window method for determining the storage period of profiles in VLR that minimises the network cost of GSM network. Further, this study examined and evaluated the computational efforts on proposed method. The proposed method proves to be better than the reported set intersection method.

Minimising network cost by employing sliding window method at mobile switching centres in GSM network

The cost effort of a global system for mobile communications (GSM) network is to be minimised for meeting effectively and efficiently the service requirements of ever increasing mobile subscriber's base. The period of temporary storage of subscribers' profiles in visitor location register (VLR) at a mobile switching centre (MSC) affects the cost of GSM network. This research study proposes a sliding window method for determining the storage period of profiles in VLR that minimises the network cost of GSM network. Further, this study examined and evaluated the computational efforts on proposed method. The proposed method proves to be better than the reported set intersection method.

New protection principle for smart grid with renewable energy sources integration using WiMAX centralized scheduling technology

The Benefit integration of distributed energy resources (DER) into distribution grid or large-scale renewable energy sources (RES) into transmission systems faces a considerable challenge to existing power system protection. In such case the coordination system of the protection is failed completely. The features given in the current standard of IEEE 802.16 solve the problem between the local and wide-area networks by providing an advanced system for metropolitan environments. This feature can be addressed to solve many traditional protection problems. The paper produces new protection solution to identify the faulted zone properly using IEEE 802.16 wireless protocol. Selecting 802.16 as a mesh mode will help allocation of minislots handling the centralized and distributed scheduling mechanisms. This is the first time of applying such technology in the protection system. The idea has the feature of protecting the grid as “Unit-Area” instead of “Multi-Area”. Principle of one protected zone instead of multi protection zones is used. The system consists of a base station, switching center and Intelligent Electronic Devices (IEDs). An accurate and proper decision is obtained based on shared information rather than stand alone relay decision.

Prospects for modulating the CD40/CD40L pathway in the therapy of the hyper-IgM syndrome.

The critical role of the CD40/CD40L pathway in B-cell proliferation, immunoglobulin (Ig) isotype switching and germinal center formation has been studied and described extensively in previous literature. Interruption of the CD40/CD40L signal causes hyper-IgM (HIGM) syndrome, which has been classified and recognized as a group of rare inherited immune deficiency disorders. Defects in CD40 and CD40L interactions or in downstream signaling molecules, including activation-induced cytidine deaminase, uracyl-DNA-glycosylase, NF-κB and DNA repair enzymes, result in an increased level of serum IgM and a significantly decreased or absent level of IgA, IgG and IgE that is accompanied by severe recurrent infections and autoimmune diseases. Many genetic defects in HIGM have been identified and, as a result, it is possible for patients to be definitively diagnosed by gene sequencing and to delineate the immunological features of the patients. Modifying the CD40/CD40L signaling pathway may offer the possibility of restoring the normal serum Ab production and curing the immunodeficiency. Hematopoietic stem cell transplantation has achieved a high rate of success using a sibling donor. In addition, successful examples of treating other immunodeficiencies using gene therapy indicated that there was a possibility of eradicating HIGM with this approach. In this review, we summarize the current drugs and a variety of therapeutic approaches for the treatment of the HIGM syndrome by interfering with the defective CD40/CD40L pathway.

Nonlinearity and chaos in wireless network traffic

The natural complexity of wireless mobile network traffic dynamics has been assessed in this article by tracing the presence of nonlinearity and chaos in the profile of daily peak hour call arrival and daily call drop of a sub-urban local mobile switching centre. The tools like Recurrence Plot and Recurrence Quantification Analysis (RQA) has been used to reveal the probable presence of non-stationarity, nonlinearity and chaosity in the network traffic. Information Entropy (IE) and 0–1 test have been employed to provide the quantitative support to the findings. Both the daily peak hour call arrival profile and the daily call drop profile exhibit non-stationarity, determinism and nonlinearity with the former one being more regular while the later one is chaotic.

A novel CoMP-ROF communication network system based on photonic decuple frequency and optical delay interference

A novel multidirectional low cost coordinated multi-point radio over fiber communication system architecture based on photonic decuple frequency and optical delay interference is proposed and deduced theoretically. At the switching center station, the multi-order photonic millimeter wave is generated by a double arm Mach-Zehnder optoelectronic modulator, and the characteristics of the multi-order photonic millimeter wave are analyzed and verified. At the base station (BS), two photonic millimeter signals are demodulated by an optical delay interferometer. The one photonic millimeter signal is used for generating fifth order upper spectrum band and fifth order lower spectrum band via an optical filter, and then the electronic millimeter signal with 30 GHz is generated by photonic decuple frequency technique. The other photonic millimeter signal is separated into two optical signals via an optical splitter, which are used for generating the third order lower spectrum band signal and the third order upper spectrum band signal respectively. After transmitting 30 km in a SSMF, the clear eye diagram and the good bit error rate are obtained for downlink signal, uplink signal and BS to BS link signal. Thanks to the photonic decuple frequency technique, the cost of the local oscillator with ultra-high frequency is greatly reduced at the BS. Because of no laser optical source, the complexity of the BS is simplified. Owing to the coordinated multi-point technique, ultra-high speed transmitting between the mobile station and the BS can become a reality on the edge of the cell.

Analysis of Signal Intelligence for Wireless Communication Systems

This paper deals about developing things that could be done with signal intelligence of wireless communication systems. It is mainly focused on connection drop problems. Most of people in this generation are using different types of mobile devices for various purposes. Here mobile means anything in motion. Now-a-days we experience lot of increase in data traffic during signal transmission between networks. The drop-connection problems and data losses are common. The situation has been improved from this decade. We still facing big problems in network hardware & managing traffic. Hence, we need to smartly manage traffic, data load and rectify errors in hardware systems in transmitter, receiver. Keywords: MSC - Mobile Switching Center; BTS - Base Transceiver Station; LTE - Long Term Evolution

Performance evaluation of mobile communication system with reliability measures

Purpose – The purpose of this paper is to evaluate performance of mobile communication system with reliability measures. Design/methodology/approach – The mobile communication system consists of a mobile station (MS), base transceiver station (BTS), base station controller (BSC) and the mobile switching center. The MS is connected to BTS, BTS is connected to BSC and BSC is connected with the mobile switching system. With the help of these stations working, the authors have developed a mathematical model using Markovian approach. Findings – Using the supplementary variable technique, the Laplace transformations and Markov process theory, the reliability indices of the mobile communication system are determined. Originality/value – In the present work, the authors have developed a mathematical model based on a mobile communication system.

Application Research of Mobile Database Model Based on Ad Hoc Network

Mobile database is a kind of distributed database which is able to support mobile computing. For traditional mobile database model, there are some problems in Ad hoc network such as significant increase in the number of transaction conflicts, in communication costs, etc. Therefore, it is necessary to improve the traditional mobile database model. The paper aims at proposing algorithms of data synchronization and transaction redo etc. to enable mobile host to get access to the database efficiently and correctly. The experimental results show that the new mobile database model has good stability. 1. Preface With the development of network technology, information technology and database technology, mobile application has gradually changed people's life and work. However, as a main support of mobile application -- mobile database is able to meets the needs of getting the information that one needs anytime and anywhere. That is to say a new era has opened up and it would have gradual impact on us in every aspect. Traditional mobile database model mainly includes server, mobile support node and mobile host. The traditional mobile database has the following problems: the location of the mobile node is not fixed, the network communication is not symmetrical, and disconnections of the network occur frequently, the storage capacity and the processing ability are limited. However, the network based on traditional mobile database model has a large number of basic communication facilities such as base stations, mobile switching centers, etc., and most of them have been built around the city. Therefore, it is not necessary to consider too much about the effects of environment. As a multi-hop, centerless, self-organizing wireless network, Ad hoc network is adopted mostly because the environment or other factors are not conducive to laying infrastructure or the infrastructure has been damaged. In reality, one of the typical applications of Ad hoc network is for the investigation teams to perform field missions, to help disaster relief, and mine surveying, etc. In Ad hoc network, in view of the reasons such as limited capacity of energy and storage of the mobile host, limited bandwidth, and frequent disconnections with the master server, etc., it will bring about a lot of problems to apply the traditional database model to Ad hoc networks, it is necessary to improve the traditional mobile database model to accommodate Ad hoc network. Many experts have done in-depth study on mobile database, including Mallikharjuna Rao, N. Naidu, etc. who have applied fuzzy database to mobile database model, thus it solved the problem of uncertain data storage, improved the performance of mobile database model; Le Gruenwald, Shankar M. Banik, who also provides the methods of

Measurement of Mobile Switching Centres Throughput in GSM Network Integrating Sliding Window Algorithm with a Single Server Finite Queuing Model

The sliding window algorithm proposed for determining an optimal sliding window does not consider the waiting times of call setup requests of a mobile station in queue at a Mobile Switching Centre (MSC) in the Global System for Mobile (GSM) Communication Network. This study proposes a model integrating the sliding window algorithm with a single server finite queuing model, referred to as integrated model for measurement of realistic throughput of a MSC considering the waiting times of call setup requests. It assumes that a MSC can process one call setup request at a time. It is useful in determining an optimal sliding window size that maximizes the realistic throughput of a MSC. Though the model assumes that a MSC can process one call setup request at a time, its scope can be extended for measuring the realistic throughput of a MSC that can process multiple call setup requests at a time.

Degenerate Hopf bifurcations in a family of FF-type switching systems

The theory of Hopf bifurcation for switching systems is different from that for smooth systems because the nonsmoothness may produce more limit cycles. Although some results were obtained and several versions of order were given for switching weak foci, few works were found for switching centers or the general relationship between order and cyclicity. In this paper we study degenerate Hopf bifurcations in a family of FF-type switching systems, whose unperturbed upper system and lower one both have the same equilibrium of linear center type on the sole switching line. We use fractional orders to uniform the concept of order of weak foci for both the smooth case and the switching one and generally discuss the relationship between the order of weak foci and the cyclicity and give the uniform upper bound for the cyclicity in terms of the Bautin depth of the ideal generated by the switching Lyapunov quantities. Moreover, we investigate the independence of those switching Lyapunov quantities. We finally apply our results to a family of switching quadratic Bautin systems and prove that the cyclicity is at least 5 and 8 in the cases of weak foci and centers respectively.

A bidirectional WDM‐PON‐ROF communication network architecture based on optical sextuple frequency

ABSTRACTA unusual bidirectional low cost WDM‐PON‐ROF communication network architecture using optical sextuple frequency which is based on photoelectron coherent modulation through a Double‐Arm‐Mach‐Zehnder‐Modulator with a number of different wavelength characteristics is provided and analyzed theoretically. After transmitting more than 25 km in a standard single mode fiber, the clear eye‐diagram and good bit error rate are obtained for wireless signal, wired signal and upstream signal communication. In this communication network architecture, because of no laser source, the base‐station (BS) is not complicated, and because of the optical sextuple frequency signal, the ultra high frequency of the local oscillator is greatly reduced. Compared with recent schemes, the outlays of switching center and BS are greatly decreased. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2079–2083, 2015

The Accuracy of Small Area Sampling of Wireless Telephone Numbers.

The value of telephone surveys for assessing effects at geographic areas is impacted by increasing wireless telephone use. Highly accurate landline samples may be drawn for national, state, county, or even smaller areas; however, wireless samples have less geographic precision. This requires additional data collection effort and screening costs in order to ensure the appropriate geographic area is surveyed. In this paper, we examine the accuracy of wireless sample frame from the 2010-2011 National Flu Surveys. We illustrate differences and variations in wireless sampling accuracy for different geographic areas, focusing on variability by area in placement of wire centers related to residences. Our results suggest that the accuracy of wireless sampling may be dependent on differences in geographic areas with the accuracy of wireless sampling decreasing as the level of geographic aggregation gets more specific; landline accuracy remains relatively stable regardless of geographic specificity. To explain this phenomenon, we examine patterns of geographic dispersion of wireless telephone numbers related to telephone switch centers and geographic area. Based on the evidence from these surveys we present several options to estimate the geographic specificity of an area prior to sampling.