Electrical/electronics Engineering

Quality of service is a vital performance indicator that is used in determining the efficiency of an industry in terms
of services rendered. Delivering excellent service is a winning strategy. Quality service sustains customers' confidence and is
essential for a competitive advantage. In telecommunication system, accessibility, retainability and connection (voice) quality
are three major factors used in evaluating quality of service of an operator. Etisalat , as one of the leading
telecommunication industry in Nigeria, it is expected that maximum satisfaction be derived by their customers in regards to
any service(s) paid for. This paper has therefore aimed at suggesting on how to improve on the quality of services rendered
by Etisalat Nigeria.

This paper is on the performance evaluation of convolutional encoders of different rates with consraint length 7 and
viterbi decoders. Shannon’s capacity theory has shown that it is theoretically possible to transmit information over a channel at
any rate with an arbitrary small error probability. Path loss and path fading can introduce errors to the signal during
propagation, thus channel coding is introduced to overcome these problems. Convolutional codes are non blocking codes that
can be designed to either correct or detect errors. The approach adopted in this research was to use information from various
technical journals, research data and world-wide user’s experiences to evaluate configurable rate convolutional encoder with
Viterbi decoder from a mother code rate 1/2 and a constraint length 7 with other higher rates of 2/3, 3/4 and 5/6 to ascertain
their performances. The Convolutional encoders have proved to be a veritable tool for reducing the effects of noisy transmission
channels.

Nigeria as fondly called the ‘giant’ of Africa has experienced series of insurgency attacks in the recent past. These
attacks have claimed many lives and properties worth billions of naira destroyed. The recent abduction of over 200 Chibok
school girls by the dreaded Bokoharam groups has provoked the entire world to seek for an alternative means of combating this
negative menace. The big question comes to our mind; “WHERE DO WE GO FROM HERE”. The solution to this question is
not too difficult to arrive at this point in time. Radar technology is the answer. Radar means Radio Detection and Ranging. It is a
means of getting information about distant objects or target, by flinging electromagnetic waves at them and analyzing the
echoes. The basic principle behind radar is simple - extremely short bursts of radio energy (traveling at the speed of light) are
transmitted, reflected off a target and then returned as an echo. This paper aims at exploring the use of Radar systems in tacking
insurgency in Nigeria

Regular monitoring of the condition of transformer is not only economical, but also adds to increased reliability. In the
past, maintenance of transformers was done based on a pre-determined schedule. With the advancement of communication
technology now it is possible to receive fault information of transformer through GSM technology. This paper presents the
implementation of Global Systems for Mobile Communication (GSM) in detecting fault in microcontroller based power
transformer. The design was achieved with microcontroller and other integrated circuit. The microcontroller thus monitors the
phases of the distribution lines from the transformer for power failure, over-voltage, under-voltage and total power outage. At
fault detection, the system will automatically send a notification message to the power station management, about the conditions
of the transformer, its location and the transformer site code for easy location and quick response for possible power restoration.

This paper is on the Technical Assessment between Worldwide Interoperability for Microwave Access (WiMAX) and Wireless Fidelity (Wi-Fi). WiFi and WiMAX are closely evaluated and compared. The technical performance evaluation of the two technologies are done based on the information obtained from research works, reports, journals, with more emphases on range and coverage, Scalability, frequency band, Channel Bandwidth, Bandwidth Efficiency, Radio Technique, Security, Mobility, Quality of Service (QoS) etc. From the result obtained from this study, it is concluded that WIMAX technology, although new points out to be better in terms of mobility, bandwidth efficiency, scalability, security, channel bandwidth, and Maximum Coverage.

This research paper focuses on Wireless Underground Sensor Networks (WUSNs). Wireless Underground Sensor Networks (WUSNs) is a specialized kind of WSN that mostly focuses on the exploit of sensors at the subsurface area of the soil. It can be used to monitor a variety of conditions, such as soil properties for agricultural applications and toxic substances for environmental monitoring, border patrol, and infrastructure monitoring. They are deployed completely below ground and do not require any wired connections. Each device contains all necessary sensors, memory, a processor, a radio, an antenna, and a power source. The benefits of WUSNs are seen in Timeliness of data, Reliability, Coverage density, Concealment, Ease of deployment. The Soil Subsurface Wireless Communication (SSWC) channel model is essential for the development of cross-layer communication solutions for WUSNs and for the development of underground to aboveground and aboveground to underground channel models for WUSNs. The results from this research confirm that the wireless underground channel exhibits a smaller attenuation at low burial depths, presents a high degree of temporal stability compared to its air counterpart, and is negatively affected by the volumetric water content (VWC) of the soil.

The purpose of this paper is to analyze Internet
network Security breaches as it affects computer systems.
As cost-effective and quick-to-deploy as the Internet is, there
is one fundamental problem – security. Some of the
―vehicles‖ that hackers use to conduct these illegitimate
activities are Trojan horse programs , Backdoor and Remote
administration , Unprotected Windows shares , Mobile Code ,
Cross-Site Scripting, Email Spoofing , Email-born Virus ,
Hidden File Extensions, Packet sniffing etc. To lessen the
vulnerability of the internet network Security breaches, there
are many products available. These tools include Encryption,
IPSec, Identification and Access Anti‐Malware Software,
Secure Socket Layer, intrusion‐detection, firewalls.

This research paper is on the
technical
performance evaluation between Global System for Mobile
Communication (GSM)
and Code Division Multiple Access
(CDMA)
technology. GSM and CDMA are
the two dominant
technologies for mobile communication. Both technologies have
the same goal of dividing the finite Radio Frequency (RF)
spectrum between the multiple users.
The technical performance
evaluation of the two technologies are
done
based on the
information obtained from research works, reports, journals,
with more emphases on
global reach, data transfer speed,
security factors, clarity, traffic, capability, compatibility,
spectrum frequencies, radiation exposure etc.
GSM uses timesharing
protocol techniques, while CDMA uses spread spectrum
techniques
for its transmission.
The outcome of this technical
evaluation
shows that CDMA is a better technology as compared
to GSM.

This research is on the analysis of data security approach for digital computers. The three basic security factors to consider are Confidentiality, Integrity and Availability, while the concepts relating to the people who can access a particular data are authentication, authorization and non-repudiation. The method of cryptography helps in securing information on the internet. Private and public key encryption ensure that only the intended recipient can read confidential information or have access to data. This research analysis has aimed to act as a gadfly for future researchers to rely on.

This paper evaluates the advantages of both
microwave and infrared technology and examines some
crucial issues where each technology provides added
value. Both Microwave and Infrared transmission
systems are use for short distance network connections.
They need line-of-sight and have its merits and
demerits. The evaluation of the two transmission
systems were in the areas of frequency spectrum,
bandwidth, technical issues, confidentiality, security
issues, distance coverage etc. From the research, it was
found that when frequency spectrum licensing is
difficult and expensive to obtain, infrared transmission
systems have a good advantage, and infrared
transmission system is less inclined to be intercepted.
Microwave transmission systems are advantageous in
areas that are foggy and are extensively use when
distance is less than four (4) miles.

This paper is on the analysis of Reed-Solomon (RS) Codes as an efficient code for error detection and
correction. Reed-Solomon codes are examples of error correcting codes in which redundant information is added to data
so that it can be recovered reliably despite errors in transmission or storage and retrieval. They describe a systematic way
of building codes that can detect and correct multiple errors. It can be used in any communication system where a
significant power saving is required and where the operating signal–to–noise ratio is very low. Deep space
communications, mobile satellite/cellular communications, microwave links, paging,

This research presents a step by step approach in modeling and simulation of Frequency Modulated (FM) radio channel using MATLAB and SIMULINK. FM radio channels are designed to allow carrier frequencies between 88 and 108MHz. Building Frequency modulated radio channels is quite a demanding task. This is because hit and trial experimentation are too costly and problems encountered in such designs looks too complicated to be analyzed. Buying the real network devices and tools required to establish or deploy a complete system is very costly. To overcome these problems, researchers and software engineers developed different system simulation tools that can help design and simulate a complete network system before embarking on the actual prototype. The results obtained from the simulated models prove the capability of MATLAB and SIMULINK as a tool for adequately predicting performance and behaviour

Electromagnetic waves are produced by stream of photons travelling in waves. They come in a very wide range of wavelengths, which include radio wave, microwave, infrared (heat), visible light, ultraviolet, X-ray, and gamma-ray waves. They are used in medicine in one way or another.  These waves travel through empty space as well as through air and other mediums. In this research, attempts are made to explore different ways in which electromagnetic waves can be useful in human medicine and also some of the hazards of Electromagnetic waves.