Informatics Publishing Limited

K. M. Rajasekaran ¹, S. Tamilselvan ²

Affiliations
1 Department of ECE, Adhiyamaan College of Engineering, Hosur, IN
2 Department of ECE, Pondicherry Engineering College, Pondicherry, IN

Abstract

The emerging broadband wireless access technology based on IEEE 802.16 is one of the most promising solutions to provide ubiquitous wireless access to the broadband service at low cost and is being actively promoted by the Worldwide Interoperability for Microwave Access (WiMAX) Forum: an industry-led consortium. Based on the IEEE 802.16, WiMAX can support a very high capacity, wide area mobility, and multimedia services with different traffic characteristics and various quality-of-service (QoS) requirements. This paper proposes an efficient uplink bandwidth request allocation algorithm for real-time services in Mobile WiMAX networks based on IEEE 802.16e. In order to minimize bandwidth wastage without degrading quality of service, the algorithm introduces a notion of target delay and dual feedback approach. The proposed algorithm calculates the amount of bandwidth request such that the delay is regulated around the desired level to minimize delay violation and delay jitter for extended real-time services. Also, it can increase utilization of wireless channel by making use of dual feedback, where the bandwidth request is adjusted based on the information about the backlogged amount of traffic in the queue and the rate mismatch between packet arrival and service rates. Due to the target delay and dual feedback, the proposed scheme can control delay and allocate bandwidth efficiently while satisfying QoS requirement. The performance is evaluated in terms of queue regulation, rate adaptation, delay controllability, and robustness to traffic characteristics. Finally, the performance of optimal bandwidth allocation is compared for extended real-time services and real-time services in mobile WiMAX networks.

Keywords

Mobile WiMAX Networks, IEEE 802.16, Uplink Scheduling, Bandwidth Request, Quality of Service, Real-Time Service.

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S. Tamilselvan ¹, R. Madhivanan ², K. M. Rajasekaran ³

Affiliations
1 Department of ECE, Pondicherry Engineering College, Pondicherry, IN
2 Department of ECE, Christ College of Engineering and Technology, Pondicherry, IN
3 Department of ECE, Adhiyamaan College of Engineering, Hosur, IN

Abstract

Wireless network refers to any type of computer network that is wireless, and is commonly associated with a telecommunications network whose interconnections between nodes are implemented without the use of wires. To accommodate various features of wireless networks, the 2D uplink and downlink wireless CAC problems are decomposed into two independent 1D CAC. To formulate the 1D CAC optimizations, the demands of service providers and subscribers are jointly taken into consideration. To solve the optimization problem, a utility and fairness-constrained optimal revenue policy and corresponding approximation algorithm is developed. Optimal utility and optimal revenue were obtained by using fairness constrained greedy algorithm. The average revenue and the blocking probability were determined. In order to compare the performance of different traffic arrival rate the utility and fairness constrained optimal revenue algorithm has been implemented. Simulation results are presented to demonstrate the effectiveness of the proposed wireless approach.

Keywords

Call Admission Control (CAC), Optimization, Orthogonal Frequency-Division Multiple Access (OFDMA), Time-Division Duplex (TDD).

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S. Tamilselvan ¹, C. Tamizhselvan ²

Affiliations
1 Department of ECE, Pondicherry Engineering College, Pondicherry, IN
2 Electronics and Communication Engineering, Pondicherry Engineering College, IN

Abstract

Nowadays the demand for various multimedia services requiring high capacity increases, shortage of wireless resources becomes a serious problem in cellular networks. It is difficult to suddenly increase the capacity of current wireless communication networks because of high cost and complexity. In order to increase the capacity of wireless communication networkswith minor changes and low cost, internetworking is needed.

Keywords

Media Independent Handover (MIH), HNE, HTCE, Vertical Handover.

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S. Vasanthakumar ¹, S. Tamilselvan ², G. Annalakshmi ²

Affiliations
1 Department of Electronics and Communication Engineering, Pondicherry Engineering College Pondicherry University, Pondicherry-605014
2 Department of Electronics and Communication Engineering, Pondicherry University, Pondicherry, IN

Abstract

The main feature of the next-generation wireless systems will be the convergence of multi-media services such as speech, audio, video, image, and data. This implies that a future wireless terminal, by guaranteeing high speed data, will be able to connect to   different networks in order to support various services: switched traffic, IP data packets, and broadband streaming services such as video. Multicarrier code-division multiple-access (MC-CDMA) scheme is the promising candidate for future broadband wireless systems, as it provides higher flexibility, transmission rates and spectral efficiency. It combines an orthogonal frequency division multiplexing (OFDM) modulation with a code-division multiple-access (CDMA) scheme and hence exploits the advantages of   OFDM as well as CDMA.

A well-known, major drawback of conventional orthogonal frequency-division multiplexing (OFDM) transmission schemes is their strong envelope fluctuation and high peak-to-mean envelope power ratio (PMEPR), leading to power amplification difficulties. That is the OFDM signal which is the superposition of large number of modulated subcarriers, usually exhibits a high instantaneous peak value with respect to average value leading to envelope fluctuations. This is cited as a major drawback in OFDM scheme. This drawback is found in MC-CDMA too.  As MC-CDMA signals have high envelope fluctuations and a high peak-to-mean envelope power ratio (PMEPR), which leads to amplification difficulties.

In order to avoid the out-of-band  radiation levels which are inherent to nonlinear distortion, power amplifiers for OFDM transmission are required to have linear characteristics and/or a significant input back off  has to be adopted. Therefore, reduced power efficiency is the price to pay for a high bandwidth efficiency. A class of low-complexity signal-processing schemes for reduced PMEPR, spectrally efficient MC-CDMA transmission was proposed.

Keywords

Clipping, Envelope Fluctuations, PAPR, PMEPR.

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S. Tamilselvan ¹, K. Manivannan ¹

Affiliations
1 Pondicherry Engineering College, Pillaichavadyt, Pondicherry, IN

Abstract

Code Division Multiple Access (CDMA) cellular system that provides seamless connectivity is featured by soft handoff, which is accompanied by power control, selection diversity and rake receiver. In IS-95/CDMA-2000 based handoff schemes or systems some handoff calls unnecessarily occupy multiple channels with little contribution to the performance of handoffs. It is noted that new calls are blocked due to the channel resource shortage. In order to efficiently utilize the channel resource those extra channels occupied by handoff calls are grouped into a set called channel convertible set (CCS) by considering the relative mobility of the call. A new scheme called Channel-Conversion with Dynamic Guard channel reservation (CCDG) that reallocates those extra channels in the CCS to new handoff calls when there is no available channel in the system is proposed. According to the variation of the CCS the scheme dynamically adjusts the number of guard channels reserved exclusively for handoff, which still enhances the system performance. It is noted that the proposed scheme can significantly decrease both the number of dropped handoff calls and the number of blocked calls without degrading the quality of communication service.

Keywords

CDMA, Power Control, Handoff, Guard Channel.

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S. Tamilselvan ¹, S. Kalaiselvan ¹, K. Manivannan ¹

Affiliations
1 Pondicherry Engineering College, Pillaichavady, Pondicherry, IN

Abstract

The unbalanced traffic load in the cellular Code Division Multiple Access (CDMA) system occurs frequently, and it may lead to system performance deterioration. In this paper, new soft handover (SHO) algorithm with adaptive handover thresholds is proposed to resolve this problem. The basic objective of the adaptive algorithm is to modify the coverage among the serving cells based on the load distribution, and consequently attain the traffic load balancing in the service regions. According to the simulation results, the proposed algorithm can balance the traffic load and has better overall performance compared with the Universal Mobile Telecommunication System (UMTS) SHO algorithm with fixed handover thresholds. In particular, the new adaptive algorithm can be implemented in the UMTS system without any alteration.

Keywords

CDMA, UMTS, Soft Handoff, Load Distribution, Threshold, Coverage.

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S. Tamilselvan ¹, J. Harinarayanan ¹, K. J. Thirunavukarasu ¹, S. Siva ¹

Affiliations
1 Arunai Engineering College, Tiruvannamalai, IN

Abstract

Multilevel inverter have become more popular over the years in electric high power application with the promise of less disturbance and reduced harmonic distortion without a transformer. This paper proposes performance evaluation of three phase Flying Capacitor Multilevel Inverter (FCMLI), under various modulating techniques for various loads When the level of Inverter is increased the power quality issues such as Harmonics and the Electromagnetic Interference were decreased. Here the 3-Phase FCMLI is analysing under Sinusoidal Pulse Width Modulation. The Proposed 3-Phase FCMLI scheme is capable of producing two-level to five-level pulse width modulated voltage depending on the modulation range. Simulation tests have been conducted that PODPWM methods provide output with relative low distortion and COPWM provides relatively higher Vrms output voltage for induction motor-load.

Keywords

Flying Capacitor Multi Level Inverter (FCMLI), Pulse Width Modulation (PWM), Total Harmonic Distortion (THD), VRMS, Crest Factor (CF), Form Factor (FF), Distortion Factor (DF).

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V. Kamalakannan ¹, S. Tamilselvan ¹

Affiliations
1 Department of Electronics and Communication Engineering, Pondicherry Engineering College,Pillaichavadi, Puducherry – 605014, IN

Abstract

Objectives: To design efficient hybrid architecture for data security is applied for securing communication link between two user/senders by considering symmetric key algorithm and asymmetric key algorithm. Methods/ Analysis: A highly efficient architectures for data security is applied for securing communication link between two user/senders in cloud integrated Internet of Things (IoT). Data is encrypted with Advanced Encryption Standard (AES) algorithm and Elliptical Curve Cryptography (ECC) concept is used for securing the secret key between user/ sender and system/receiver. In this architecture authentication is provided by Elliptic Curve Diffie Hellman algorithm between user/sender and system/receiver. The efficient hybrid architecture is implemented on Field Programmable Gate Array (FPGA) and is scripted in verilog Hardware Description language (HDL).Findings: According to the IoT concept, Radio Frequency Identification (RFID) and Wireless Sensor Networks (WSN) meet new challenges related to large volume of data. The physical things in an IoT are generally identified by WSN or RFID before connecting with each other. Once identified, they can interchange data between them. Cloud computing provides virtual infrastructure for storing, analyzing, and virtualization large data in client delivery. Data transferring like storing and retrieving from cloud by different user/senders should be secure from Men in the Middle (MIM) attack of information. The outcomes obtained shows that the efficient cryptosystem with encryption and decryption has a minimum period of 18.060ns with the maximum achievable frequency of 55.371MHz on Xilinx Virtex-5 (XC5VLX50T-1FF1136).Novelty/ Improvement: In this paper ECC algorithm is for providing security communication between user/senders and system/receiver. ECC encryption is used for encrypting the request of user/senders connected to the receiver. The file in the system/receiver is accessed by the user/sender and the file is encrypted by system/receiver using user/ sender’s public key. When uploading the files system/receiver encrypts the file using AES encryption algorithm or while downloading the file from data storage the system/receiver decrypts the data or file using AES algorithm.

Keywords

Advanced Encryption Standard (AES), Cloud Computing, Elliptic Curve Cryptography (ECC), Elliptic Curve Diffie-Hellman-Merkle, Internet of Things (IoT), Key Exchange.

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V. Gunasekaran ¹, K. Mohanasundaram ¹, M. Dhandapani ¹, S. Tamilselvan ¹, S. Arivarasan ¹

Affiliations
1 Department of Electrical and Electronics Engineering, Vel Tech Multitech Dr. Rangarajan Dr. Sakunthala Engineering College, Avadi, Chennai - 600062, Tamil Nadu, IN

Abstract

Background: Due to greater potential to accelerate a wide variety of application, reconfigurable FPGA has become a subject to great deal of research. The FPGA has ability to perform computations in hardware to increase the system performance, while retaining much of the flexibility of software solutions. In recent development, the real-time embedded system are increasingly being built with COTS components namely mass-produced peripherals and by reducing cost through buses and performance improvement. But the available COTS systems do not guarantee any timeliness and do not implement any priority scheduling mechanism. Methods/Statistical Analysis: This article deals with a new approach to create an RTOS based reconfigurable COTS design for FPGA platform. Thereby RTOS kernel is designed for FPGA and COTS system designed on the FPGA. Application/Improvements: At runtime, the hardware tasks are scheduled and allocated system resources like I/O, memory, etc. to successfully export multiple virtual devices for a single physical device.

Keywords

FPGA, RTOS based Reconfigurable Commercial-off-the-Shelf

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CH. V. M. S. N. Pavan Kumar ¹, S. Tamilselvan ¹

Affiliations
1 Department of ECE, Pondicherry Engineering College, ECR Road and VSR Street, Pillaichavadi, Puducherry - 605014, IN

Abstract

Background/Objective: The demand for the data traffic is exponentially increasing day to day because of the proliferation of smart phones, tablets and internet-connected devices. To meet this requirements network operators has to dramatically increase their network capacities. Methods: One of the possible ways to increase the system capacity is bringing the transmitter and receiver nearer to each other. It gives dual benefits higher quality and spectrum efficiency. Findings: The cost effective solution is installing the low power nodes instead of traditional high power macro base stations. Examples of these low power nodes are microcells, picocells, femtocells and distributed antenna systems. The network, which consists of different power nodes, architectures, and protocols is called Heterogeneous network. To overcome the indoor coverage and increased system capacity femtocells also called low power base stations are selected by the researchers as the suitable solution. In this paper we overview the femtocell deployment scenarios, access modes, and technical challenges briefly. Improvements: This paper gives the details about solutions available in the literature and gives future research directions to solve the technical challenges faced by femtocells.

Keywords

Femtocell, Heterogeneous Network, 3GPP, Interference Management, Smallcell

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V. Kamalakannan ¹, S. Tamilselvan ²

Affiliations
1 Department of Electronics and Communication Engineering, Pondicherry Engineering College, Pillaichavady – 605014, Puducherry,, IN
2 Department of Electronics and Communication Engineering, Pondicherry Engineering College, Pillaichavady – 605014, Puducherry, IN

Abstract

Background: Today’s developing era data and information security plays an important role in unsecured communication between Internet of Things (IoT) elements. As the technologies are developing huge amount of information are exchanged with each other which increases the demand of a secure encryption standards. Objectives: To protect the information transmission between nodes in the perceptual layer of IoT, security is to be enhanced such that the Men in Middle (MIM) attack of information by intruders in the communication link is not possible. Methods/Statistical analysis: The security method is implemented using the concept of symmetric, asymmetric and hash algorithms between the sender and receiver. Elliptic Curve Cryptography (ECC) is performed for encrypting and sharing the Advanced Encryption Standard (AES) secret key between the sender and receiver. Elliptic Curve digital signature are added with the encrypted data for validation in transmission. Secured Hash Algorithm (SHA) is considered for generating Elliptical Curve Digital Signature Algorithm (ECDSA). All the algorithms are combined to enhance the security. Findings: Elliptic Curve Cryptography is generally applied for encrypting and sharing the secret key between the sender and receiver when Advanced Encryption Standard is used for encryption/decryption of data. A highly efficient architectures for asymmetric key encryption is applied with symmetric key encryption for encrypting the data transmitted between the devices present in the perceptual layers in the IoT. Due to security issues NIST selected SHA-3 Keccak-f[1600] algorithm. An authentication process based on ECC is applied to perceptual layer involving initialization and authentication phase apart from encryption and signature generation. Sender combines the encrypted data and key with signature together before transmitting to the receiver. The receiver verifies the signature and decrypts the key and obtains original information. Hence it is very difficult for the man in middle to access the information exchanged between the Perceptual Layer devices. Application/Improvements: This generally doesn’t require an innovative technique but an approach to develop the method implemented successfully in the perceptual layer of Internet of Things. The key is encrypted and decrypted using a novel ECC algorithm with improved ECDSA.

Keywords

Elliptical Curve Cryptography (ECC), Elliptic Curve Digital Signature Algorithm (EDSA), Internet of Things (IoT), Keccak, Perception Layer, Secured Hash Algorithm (SHA).

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Ch. V.M.S.N. Pavan Kumar ¹, S. Tamilselvan ¹

Affiliations
1 Department of Electronics and Communication Engineering, Pondicherry Engineering College,Puducherry – 605014, IN

Abstract

Background/Objectives: In earlier days of wireless communications, the demand for the spectrum is limited, because the wireless services may not require higher bandwidths. But as time passes radio spectrum has become one of the important and regulated resources for all the wireless services. From the past 10 to 15 years the spectrum needs were increased and it becomes a scarce resource. Methods/Statistical analysis: The information and communication technology industry in today’s scenario faces several global challenges like: Higher data services with improved Quality Of Service (QOS), scarcity of spectrum, and increased expenses of the services. Thus both the energy domains as well as spectral domain efficiencies were degraded, which made the researches to think in different ways, The other ways to improve spectrum utilization is the use of unlicensed spectrum or secondary access. In order to solve this spectrum utilization efficiency problem, Cognitive Radio (CR) concept was introduced. CR technology is an secondary access method in which an unlicensed Secondary Users (SUs) senses the whole radio spectrum and uses the licensed spectrum holes such that it does not cause any interference to the Primary Users (PUs). This way of spectrum access improves the efficiency of spectrum utilization. Findings: For sensing the spectrum of the primary user, several methods are proposed in literature. A method called Paraunitary Analysis Filter Bank based sensing method is analysed in this paper and its performance was compared with Filter bank based spectrum sensing and Energy Detection (ED) based spectrum sensing techniques. Application/Improvements: It can be used to reduce the interference in Femtocell networks by considering the macro user as a primary user and femto user as a secondary user to use the spectrum effectively and to increase the capacity of the cellular networks.

Keywords

Cognitive Radio, Energy Detection, Filter Bank, Paraunitary Filter Bank, Spectrum Sensing.

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S. Sivaganesan , K. Nirmala , S. Tamilselvan

Abstract

In higher order SOC (System On Chip) circuit, designs have led to drastic increase in test data volume. Larger test data size demands not only higher memory requirements, but also an increase in testing time. Test data compression addresses this problem by reducing the test data volume without affecting the overall system performance. In this, testable input data (test data) is generated by using Automatic test pattern generation (ATPG) then it is compressed and compressed data stored to memory. To test the particular circuit that time we will decompress the stored memory test data and then decompressed test data given to the Design Under Test (DUT). Finally DUT fault is tested and identified. It proposes a test compression technique using efficient dictionary selection and bitmask method to significantly reduce the testing time and memory requirements. This algorithm giving a best possible test compression of 92% when compared with other compression methods.

Keywords

Test data compression, Decompression, Dictionary selection, Bitmask, Run length, Golomb

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S. Tamilselvan ¹, P. Nithya ¹

Affiliations
1 Department of Electronics and Communication Engineering, M. Kumarasamy College of Engineering (Autonomous), Thalavapalayam - 639113, IN

Abstract

The two’s complement approach plays a vital role in reducing Partial product Rows count in signed bit multiplier. In this paper proposed a multiplier which reduces the partial product rows by Modified Booth techniques with less delay. This high performance 2’s complement multiplier is used in embedded cores. This work was implemented in the Xilinx software and simulation results were obtained for the different applications. Applications such as FIR filter and Image processing requires high accuracy and smaller size multipliers. The image and filter interfacing is done with the help of MATLAB software.

Keywords

Image Processing, MATLAB, Modified Booth Technique, Partial Product, Xilinx

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S. Tamilselvan ¹, K. Manivannan ²

Affiliations
1 Department of Electronics & Communication Engineering, Pondicherry Engineering College, Pondicherry-605014, IN
2 Department of Electrical & Electronics Engineering, Pondicherry Engineering College, Pondicherry-605014, IN

Abstract

The paper proposes joint power and rate assignment algorithm (JPRA) to deal with multirate soft handoffs in mixed size Wideband Code Division Multiple Access (WCDMA) cellular systems. The JPRA algorithm is designed in a co-operative two-phased process. The JPRA algorithm contains a link proportional power allocation scheme and an evolutionary computing rate assignment method to determine an appropriate allocation of transmission power and service rate for multirate SHOs. It can achieve good power balancing among cells. LPPA is a multi-site transmission mechanism, which distributes the power in proportion to link qualities between a SHO user and all base transceiver stations (BTS) in its active set. ECRA method performs optimal rate allocation for multi-rate SHO users.

Keywords

WCDMA, Transmission Power, Soft Handoff, Multirate, Cellular System, Base Station.

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S. Tamilselvan ¹, A. Arun ¹

Affiliations
1 Department of Electronics and Communication Engineering, M. Kumarasamy College of Engineering, Karur - 639113, Tamil Nadu, IN

Abstract

Objectives: An efficient MAC design is planned for 2’s complement numbers with no more than partial-product creation methodology and diminution tree, whereas the succeeding step trappings an extraordinary sign-conservatory solutions. Methods/Statistical Analysis: Accumulate operations form an important process in signal and image processing applications. To expand MAC execution, the basic way postponement can be diminished by embeddings an additional pipeline register, either in the interior the two rows or stuck between the twos and the final adder. Findings: The 16 bit MAC architecture is implemented using Baugh-Wooley (BW) multiplier with Twin precision concept. The proposed methodology is verified by implementing in a 16 x 16 MAC unit. The performance parameters extracted demonstrates that the proposed Modified Booth with Twin precision based 16 bit MAC demonstrates an area reduction of 45.3%, delay reduction of 30.8% and power saving of 60% when compared to the MAC architectures designed using Baugh-Wooley with twin precision multiplier. Application/Improvements: It performs better than the conventional MAC in all the aspects.

Keywords

Baugh-Wooley Multiplier, MAC Design, Partial-Product, Sign-Conservatory Solutions, Twin Precision

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