Cross-Layer Optimization in OFDM Wireless Communication Network

The wide use of OFDM systems in multiuser environments to overcome problem of communication over the wireless channel has gained prominence in recent years. Cross-layer Optimization technique is aimed to further improve the efficiency of this network. This chapter demonstrates that significant improvements in data traffic parameters can be achieved by applying cross-layer optimization tech- niques to packet switched wireless networks. This work compares the system capacity, delay time and data throughput of QoS traffic in a multiuser OFDM system using two algorithms. The first algorithm, Maximum Weighted Capacity, uses a cross-layer design to share resources and schedule traffic to users on the network, while the other algorithm (Maximum Capacity) simply allocates resources based only on the users channel quality. The results of the research shows that the delay time and data throughput of the Maximum Weighted Capacity algorithm in cross layer OFDM system is much better than that of the Maximum Capacity in simply based users channel quality system. The cost incurred for this gain is the increased complexity of the Maximum Weighted Capacity scheme

Development of iSpeak: A voice activated Relationship Management System

A constant source of frustration for subscribers of mobile telephony in Nigeria is the quality of customer care service. The ubiquitous IVR systems deployed by service providers often ends in long and winding texting of digits that terminate in calls to agents with poor CRM attitudes. Automation of most of the functions of the human agent goes a long way in mitigating this problem. This paper describes iSpeak – a system designed to reduce the human–to–human (H2H) interaction in the complaint-lodging and solution provision process to a minimal level where it is not possible to eradicate it totally by a replacement with human–to–system (H2S) interactivity. iSpeak has an inherent capacity for improving the efficiency and drastically cutting CRM cost of corporate organizations. This comes with the attendant advantage of improved business-customer relationship. Keywords – Automatic Speech Recognition, Customer Care Service, Speech-control, Customer Voice Model, Voice Print, Voice Recognition

Power Line Communication Technologies: Modeling and Simulation of PRIME Physical Layer

Power Line Communications is a relatively new area of telecommunication. PLC employs full duplex methods for transmitting data over power lines as medium of transmission of electrical signals over a grid. PLC technologies are used in advanced meter reading, home automation and Public street lighting. Several PLC technologies classified based on the operational frequency range, are explored in this paper. PRIME is a new NBPLC system, which uses OFDM in its physical layer, for power line communication in the last mile. This work also focused on PRIME’s physical specifications, which was modeled in MATLAB/SIMULINK. In this paper, the performance of PRIME when its data is modulated using DQPSK and 4-QAM in four (4) channel models is shown.

Modeling and Simulation of a University LAN in OPNET Modeller Environment

Academia has peculiar networking needs that must be satisfied for effective dissemination of knowledge. The main purpose of a campus network is efficient resource sharing and access to information among its users. A key issue with designing and implementing such Local Area Networks (LAN) is its performance under ever increasing network traffic, and how this is affected by various network metrics such as latency and end-to-end delay. Implementation of network systems is a complex and expensive task; hence network simulation has become essential and has proven to be cost effective and highly useful for modeling the desired characteristics and analyzing performance under different scenarios. As well as providing useful prognosis of future network performance based on current expansion dynamics. We present in this paper the simulation and analysis of the Covenant University campus LAN in the OPNET Modeler environment

Satellite Communications: Impact on Developing Economies

Access to information and communication infrastructure greatly enhances economic growth. When a reliable and affordable medium for information exchange is available, previously unanticipated developments ensue. Most areas in developing countries are sparsely populated and highly rural. Satellite communication is an excellent option for meeting this and many other pressing communication needs of developing economies. This paper examines the impact of satellite communication on developing economies, using popular examples as case study

Comparative Analysis of Routing Internet Protocol and Open Shortest Path First Protocols Using QUALNET

Reliability is a major consideration in Network Design and Implementation in order to cater for link failures. Link failure is a frequent occurrence in Networks and Communications Systems, and the speed at which this disruption is noticed and (or) fixed varies. The use of dynamic routing means in case of link failure, the routers are able to learn alternate routes via periodic updates about the network topology and link states from its neighbors. This report shows how to simulate and study how dynamic routing protocols such Link state and Distance-vector routing protocols respond to link failures and restart, their performance is compared using Qualnet

Comparative Analysis of Scheduling Techniques in Downlink LTE Using MATLAB-Based LTE MACLAB Simulator

Traffic scheduling plays an important role in LTE technology by assigning the shared resources among users in the most efficient manner. This research compares the performance of three types of scheduling algorithms namely: Round Robin, best Channel Quality Indicator (CQI) and Proportional Fair (PF) schedulers representing the extreme cases in scheduling. The scheduling algorithms performances on the downlink were measured in terms of throughput and block error rate using a MATLAB-based system level simulation

DESIGN AND IMPLEMENTATION OF A VIRTUAL COMPUTING ENVIRONMENT FOR SCHOOLS AND OFFICES

Aderemi, Adeyemi

Neural-Encoded Fuzzy Models for Load Balancing in 3GPP LTE

Post third generation (3G) broadband mobile networks such as HSPA+, LTE and LTE-Advanced offer improved spectral efficiency and higher data rates using innovative technologies such as relay nodes and femto cells. In addition, these networks are normally deployed for parallel operation with existing heterogeneous networks. This increases the complexity of network management and operations, which reflects in higher operational and capital cost. In order to address these challenges, self-organizing network operations were envisioned for these next generation networks. For LTE in particular, Self-organizing networks operations were built into the specifications for the radio access network. Load balancing is a key self-organizing operation aimed at ensuring an equitable distribution of users in the network. Several iterative techniques have been adopted for load balancing. However, these iterative techniques require precision, rigor and certainty, which carry a computational cost. Retrospect, these techniques use load indicators to achieve load balancing. This paper proposes two neural encoded fuzzy models, developed from network simulation for load balancing. The two models use both load indicators and key performance indicators for a more informed and intuitive load balancing. The result of the model checking and testing satisfactorily validates the model