Global Journal of Computer Science and Technology (GJCST)
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Performance Evaluation of Spatial Multiplexing MIMO-OFDM System using MMSE Detection under Frequency Selective Rayleigh Channel
Get PDFMIMO-OFDM (Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing) is a very promising technology providing high throughput and range without additional bandwidth or transmit power by using many antennas at transmitter and receiver eliminating Inter-Symbol- Interference (ISI).The capacities of MIMO-OFDM systems can be fully utilized by low complex and optimal signal detection scheme. The receiver2019;s detector is supposed to maximize the Signal to interference plus noise (SINR) by cancelling the spatial interference and should separate the transmitted signals. Minimum Mean Square Error (MMSE) detector is near optimal and less complex. The performance of the proposed system is analyzed using MMSE under flat and frequency selective Rayleigh channel environment, different number of antenna configurations and various modulation techniques to provide an optimum solution
Adaptive Genetic Algorithm Based Artificial Neural Network for Software Defect Prediction
Get PDFTo meet the requirement of an efficient software defect prediction,in this paper an evolutionary computing based neural network learning scheme has been developed that alleviates the existing Artificial Neural Network (ANN) limitations such as local minima and convergence issues. To achieve optimal software defect prediction, in this paper, Adaptive-Genetic Algorithm (A-GA) based ANN learning and weightestimation scheme has been developed. Unlike conventional GA, in this paper we have used adaptive crossover and mutation probability parameter that alleviates the issue of disruption towards optimal solution. We have used object oriented software metrics, CK metrics for fault prediction and the proposed Evolutionary Computing Based Hybrid Neural Network (HENN)algorithm has been examined for performance in terms of accuracy, precision, recall, F-measure, completeness etc, where it has performed better as compared to major existing schemes. The proposed scheme exhibited 97.99% prediction accuracy while ensuring optimal precision, Fmeasure and recall
Fuzzy Inspired Case based Reasoning for Hematology Malignancies Classification
Get PDFConventional approaches for collecting and reporting hematological data as well as diagnosing hematologic malignancies such as leukemia, anemia, e.t.c are based on subjective professional physician personal opinions or experiences which are influenced by human error, dependent on human-to-human judgments, time consuming processes and the blood results are non-reproducible. In the light of those human limitations identified, an automatic or semi-automatic classification and corrective method is required because it reduces the load on human observers and accuracy is not affected due to fatigue. Case-Based Reasoning (CBR) as a multi-disciplinary subject that focuses on the reuse of past experiences or cases to proffer solution to new cases was adopted and combined with the power of Fuzzy logic to design a software model that will effectively mine hematology data. This study aim at helping the medical practitioners to diagnose and provide corrective treatment to both normal patients and patients with hematology disorder at the early stage which can reduce the number of deaths. This aim is achievable by developing an intelligent expert system based on fuzzy logic and case-based reasoning for classification of hematology malignancy
A Novel Classifier for Digital Angle Modulated Signals
Get PDFThe identification of the modulation type of an arbitrary noisy signal is necessary in various applications including signal confirmation, interference identification, spectrum management, electronic support systems in warfare, electronic counter-counter measures etc. In this paper a novel classification scheme based on the variance of instantaneous frequency is proposed to discriminate between noisy M-ary Phase Shift Keyed (MPSK) and M-ary Frequency Shift Keyed (MFSK) signals. In the proposed method, the received signal is passed through a pair of band pass filters and the ratio of variances of instantaneous frequency of the filter outputs is used as a decision statistic. Analytic expressions are developed for the decision statistic. These expressions show that a high degree of discrimination is possible between PSK and FSK signals even at a carrier-to-noise ratio (CNR) of 0 dB. Simulation studies have been carried out and the theoretical predictions are validated
Improving Ieee 802.11 Wlan Handoff Latency by Access Point-Based Modification
Get PDFIEEE 802.11 WLAN provides multimedia services like live telecast, video streaming, video conferencing, Voice over IP (VoIP) to its users. For deployment of these fast real time services, it needs stringent Quality of service (QoS) requirement such as delay time less than 150ms for VoIP, and packet loss rate of 1%. The mobility service for users come with cost of handoff process required when mobile stations get connected from 1 Access point (AP) to another for continuous service. In existing 802.11 IEEE handoff procedure, the scanning phase can exceed duration of 200ms and packet loss can exceed 10%. Thus, proposed methodology focuses on achieving reduced overall handoff latency by implementing handoff delay duration less than 150ms which is the need for seamless service in IEEE 802.11 WLAN
A Binary Tree based Approach for Time Based Page Ranking in Search Engines
Get PDFSearch engines rank web pages according to different conditions. Some of them use publication time, some use last time of update, some checks the currency of the content of the web page. In this paper, a new algorithm is proposed which will work on the time of the web page, temporal information of the content and forms a binary tree to rank among web pages
Dynamic Permutations
Get PDFThe confidentiality integrity and authentication of anelectronic documentare necessary in many application systems The security of confidentiality integrity and authentication of an electronic document are based on nonlinear functions in which there is no directrelationship between the inputs and the outputs This means that the inputs cannot be extracted from the outputs Indeed all modern cyphers are based on the concept of substitution transposition In data encryption standard algorithm DES which consists of many functions only one nonlinear function is used in the algorithm called substitution boxes and all other functions are linear one of these linear functions is called IP initial permutation function which performs static permutations The permutations are replaced by transpositions based on predefined positions and the permutation function is used several times in DES algorith
GSM Based Agriculture Monitoring and Controlling System
Get PDFThis paper proposes a farming environment observing framework for checking data concerning an outside by using Wireless Sensor Network WSN innovation The proposed rural environment observing server framework gathers natural and soil data on the outside through WSN-based ecological and soil sensors In this paper we are using sensors as soil moisture sensor and temperature sensor This sensors help the field to control the water level and also temperature Here we are using wireless sensor network as GSM global system for mobile communicatio
The Encryption Algorithms AES-PES16-1 and AES-RFWKPES16-1 based on Networks PES16-1 and RFWKPES16-1
No full textIn this article we developed a new block encryption algorithm based on network RFWKIDEA32-1 using of the transformations of the encryption algorithm AES which is called AESRFWKIDEA32- 1 The block s length of this encryption algorithm is 256 bits the number of rounds are 10 12 and 14 The advantages of the encryption algorithms are that when encryption and decryption process used the same algorithm In addition the encryption algorithm AES-RFWKIDEA32-1 encrypts faster than AE
Security Issues and Energy Consumption in Implementing Wireless Sensor Networks
No full textThe Internet has become an indispensable means of sourcing and storing information In the future the Internet will be used to control objects not just information This raises the issue of security In the case of wireless sensor networks the main challenge will be to provide secure lines of communication between devices on the same networ