iosr-JECE   Volume-9 ~ Issue-6 ~ Nov-Dec 2014

Abstract: This paper addresses the problem of optimum waveform design for multiple target detection. The notion of poly-semantic radar, which gave improved performance through coincidence detection, is analyzed for high resolution radar system in presence of high density additive noise and Doppler shift. These sequences are optimized by employing Hamming backtrack algorithm (HBT). The detection capability of poly-semantic sequences is further improved through coincidence detection of the return signal. The simulation results show that the proposed sequences give improved robustness of noise and Doppler shift for HRR target detection compared to conventional pulse compression sequences.
Keywords: Hamming backtrack algorithm, high resolution radar, target detection.

[1] R. J. Keeler, c. A. Hwang, "pulse compression for weather radar", in proc. Ieee int. Radar conf., 1995, pp. 529-535.
[2] F. B. Dah, c. F. Juang, and c. T. Lin, "a neural fuzzy network approach to radar pulse compression", ieee trans. On geosciences and remote sensing letters., vol. 1, no. 1, 2004, pp. 15-20.
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Abstract: The aim of this paper is to evaluate the performance of LAN and VLAN networks in different scenarios, measuring performance metrics like traffic sent, traffic received, delay and collision count in the Ethernet environment. The simulation was carried out using OPNET IT GURU ACADEMIC EDITION 9.1. To observe the performance of LAN and VLAN networks three different scenarios were presented. In the first scenario, the network consists of one hub and 16 workstations; the second scenario was connected with two hubs and a switch while the third scenario VLAN is explained and detailed, the simulation results displayed that more traffic exists in the network without VLANs, since any communication between departments is allowed, when using VLANs; it is no more possible to send traffic or access the network resources of other departments, VLANs improve the bandwidth utilization, security and the administration by supporting a virtual organization.

[1] Sincoskie, WD "Broadband packet switching: a personal perspective." IEEE Commun. Mag. Volume 40, Issue 7, pp. 54-66, Jul. 2002.
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[4] Todd Lammle, Cisco Certified Network Associate Study Guide, Sybex, 6th Edition, 2007.
[5] Gyan Prakash Pal, Sadhana Pal "Virtual Local Area Network" International Journal of Scientific Research Engineering & Technology (IJSRET), Volume 1, Issue 10 pp 006-010 January 2013.

Abstract: The work presents the investigation of GMSK and BPSK transmission schemes with both MRC and EGC diversity combining techniques over Rayleigh flat fading channels in a digital mobile wireless system. The System model for the received signal was developed under two propagation paths and simulated. Randomly generated symbols and Image data, were used as the Information signal. The results obtained showed that BPSK had a higher error probability values than the corresponding GMSK scheme. The results showed that due to GMSK high immunity to noise and other interfering signals, it provides a better performance than BPSK signalling scheme. Also, MRC was observed to perform better in terms of mitigation of the interference induced by the Rayleigh channel than EGC diversity combining technique. The quality of the images received with both signalling scheme were in agreement with the BER results.
Keywords: Multipath fading, Diversity combining, Rayleigh channel, Bit error rate

[1]. Adeyemo, Z. K., and Abolade, R. O., (2011) Comparative Analysis of GMSK and BDPSK signalling scheme with MRC over a Rayleigh fading environment. Advanced Materials Research Vol. 367 (2012) Pp 205-214, Trans Tech Publications, Switzerland.
[2]. Adeyemo, Z. K. And Teslim I. R., (2010) Bit error rate analysis for wireless links using Adaptive Combining Diversity. Journal of Theoretical and Applied Information Technology, Vol20, No 1, Pp 58-60.
[3]. Adeyemo, Z. K. And Teslim I. R., (2009) Performance of Binary phase shift keying (BPSK) and Quaternary phase shift keying (QSPK) Signalling schemes in Fast and frequency Non-selective Rayleigh fading channel with Decision Feedback Equalizer (DFE) at the Receiver. Advanced Materials Research, Trans Tech Publications, Switzerland, Vols.62-64, p.99-104.
[4]. Akbar, M. S., and Behnaam, A.. (1997), Joint multipath Doppler Diversity in Mobile Wireless Communications. Department of Electrical and Computer Engineering, University of Wisconsin–Madison Madison, WI 53706. IEEE Transactions On Communications, Vol. 47, No. 1, January 1999, pp123-132.

Abstract: Wireless technology is increasing rapidly over the last two decades. It has been limited to growth in wireless radio spectrum, because the radio spectrum is a finite resource which indicates that there is significant scope of improving spectrum utilization. Cognitive Radio (CR) is the key enabling technology that improves the efficiency of spectrum utilization. The spectrum sensing gives the capability of CR to detect there is no primary user present in the band over wireless fading channels. In this paper we study the performance of BPSK modulation scheme under AWGN, Rayleigh, Rician and Nakagami-m fading channels are analyzed using bit error rate (BER). The performance compare between the different types of the fading channels using the MATLAB simulation. The simulation results show that the performance of the system is good in case of AWGN channel as compared to other fading channels and the Rician fading channel is better than the other fading channels such as Nakagami-m and Rayleigh fading channels when the value of K is large.
Keywords: Cognitive radio, BER, BPSK, Fading channels

[1]. V. M. K. a. O. S. Vaidya, "Analysis of Energy Detection based Spectrum Sensing over Wireless Fading Channels in Cognitive Radio Network," International Journal of Emerging Technology and Advanced Engineering, vol. 2, no. 3, pp. 645-653, 2013.
[2]. T. S. a. D. A. Nachiappan, "An Insight into BER Performance of Reed-Solomon coded M-FSK under AWGN, Rayleigh and Rician Fading Channels," International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering, vol. 2, no. 9, pp. 1488-1492, 2013.
[3]. S. B., "Rayleigh fading channels in mobile digital communication systems .I. Characterization," Communications Magazine, IEEE, vol. 35, no. 7, pp. 90 - 100, 1997.
[4]. S. K. B. a. S. K. Chaparala, "Performance Evaluation of OFDM System with Rayleigh,Rician and AWGN channels," International Journal of Emerging Technology and Advanced Engineering, vol. 3, no. 3, pp. 678-682, 2013.
[5]. M. M. R. M. A. I. a. A. T. I. Nuzhat Tasneem Awon, "Effect of AWGN & Fading (Raleigh & Rician)channels on BER performance of a WiMAX communication System," International Journal of Computer Science and Information Security (IJCSIS), vol. 10, no. 8, pp. 11-17, 2012.

Abstract: A cognitive radio network improves the spectrum utilization. In this paper, we present a distributed algorithm for scheduling and spectrum allocation, they maximize the networks throughput. During each time slot, the scheduling and spectrum allocation problems selecting a subset of links to be activated, and allocate the available resources to these links. This problem is considered as an aggregate utility maximization problem. The queuing analysis used to characterize the throughput and delay performance of the network and throughput is maximized by Lagrangian duality theory. The problems are divided into a set of sub problems that can be solved locally by using dual decomposition framework, & it allows us to develop distributed algorithm.

Keywords: cognitive radios, distributed algorithm, lagrangian duality theory, Resource allocation.

[1] S. A. Zekavat and X. Li, "User-central wireless system: Ultimate dynamic channel allocation," in Proc. IEEE DySPAN, Baltimore, MD, USA, Nov. 2005, pp. 82–87.
[2] J. Zhao, H. Zheng, and G.-H. Yang,"Distributed coordination in dynamic spectrum allocation networks," in Proc. IEEE DySPAN, Baltimore, MD, USA, Nov. 2005, pp. 259–268.
[3] L. Cao and H. Zheng, "Distributed spectrum allocation via local bargaining," in Proc. IEEE Conf. SECON , Santa Clara, CA,

Abstract: Denoising the hyperspectral images (HSIs) which include both signal-dependent (SD) and signal-independent (SI) noise from signal. The signal dependent noise such as electron noise due to the electrical fluctuation in the current. The photon noise occurred during calibration process. The noise removed by using various methods. To denoise HSIs distorted by both signal-dependent (SD) and signal-independent (SI) noise, some hybrid methods, which reduce noise by two steps. The first one, named as the PARAFAC SI –PARAFAC SD method. The second one is the HYperspectral Noise Estimation (HYNE) method and PARAFAC decomposition, which is named as the HYNE-PARAFAC method. The last one combines the Wiener filter (MWF) method and PARAFAC decomposition and is named as the MWF-PARAFAC method. However, conventional hyperspectral imaging suffers from limited light in individual bands which introduces noise into the imaging process. In this paper, we present a simple but effective denoising method that exploits the spectral domain

Index Terms: Denoising, hyperspectral image (HSI), PARAFAC, signal-dependent (SD) noise, signal-independent(SI), Multidimensional Wiener Filter(MWF).

1]. J. M. P. Nascimento and j. M. Bioucas-dias, "hyperspectral unmixing based on mixtures of dirichlet components," ieee trans. Geosci. Remote sens., vol. 50, no. 3, pp. 863–878, mar. 2012.
[2]. N. Renard and s. Bourennane, "improvement of target detection methods by multiway filtering," ieee trans. Geosci. Remote sens., vol. 46, no. 8, pp. 2407–2417, aug. 2008.
[3]. R. Archibald and g. Fann, "feature selection and classification of hy- perspectral images with support vector machines," ieee trans. Geosci. Remote sens., vol. 4, no. 4, pp. 674–677, oct. 2007.
[4]. N. Acito, m. Diani, and g. Corsini, "signal-dependent noise modeling and model parameter estimation in hyperspectral images," ieee trans. Geosci. Remote sens., vol. 49, no. 8, pp. 2957–2971, aug. 2011.
[5]. p. Rakwatin, w. Takeuchi, and y. Yasuoka, "stripe noise reduction in modis data by combining histogram matching with facet filter," ieee trans. Geosci. Remote sens., vol. 45, no. 6, pp. 1844–1856, jun. 2007.
[6]. m. Uss, b. Vozel, v. Lukin, and k. Chehdi, "local signal-dependent noise variance estimation from hyperspectral textural images," ieee j. Sel. Topics. Signal process., vol. 5, no. 3, pp. 469–486, jun.2011.

Abstract: The aim of Vehicular Adhoc networks(VANETS) is to control the road traffic. This paper address an improved authentication scheme for Radio Frequency Identification (RFID) applied in VANETs. In earlier the authors used symmetric key cryptography with EKA2,for that authentication delay will occur. To overcome this we proposed an group based authentication asymmetric key cryptography with IKEV2 key management. This improves the authentication of RFID and provide the better computation efficiency in VANETs and reduced the complexity of symmetric key management system.

Keywords: RFID, VANETs, key management, Authentication

[1] L. Eschenauer and V. D. Gligor, "A key-management scheme fo rdistributed sensor networks," in Proceedings of the 9th ACMconference on Computer and communications security, CCS ‟02, (NewYork, NY, USA), pp. 41–47, ACM, 2002.
[2] B. Parno, and A. Perrig "Challenges in securing vehicular networks," In Proc. of the Int.Workshop on Hot Topics in Networks (HotNets-IV), 2005XI Y., SHA K., SHI W., SCHWIEBERT L., ZHAN

Abstract: A wireless sensor network (WSN) consists of a large number of wireless sensor nodes. Since wireless sensor nodes are battery powered devices, they have limited processing and transmission power. In order to transmit sensing data to receiver effectively, it is important to design a routing protocol for WSNs. Since energy conservation is a key issue in WSNs, data aggregation should be exploited in order to save energy. In this case, redundant data can be aggregated at intermediate nodes reducing the size and number of exchanged messages and, thus, decreasing communication costs and energy consumption. This paper propose a Forward Aware Factor-Energy Balanced Routing Method (FAF-EBRM). In the experiments, this method is compared with LEACH. Experimental results show that this method FAF-EBRM outperforms LEACH, which balances the energy consumption, prolongs the network function lifetime and provides the best aggregation quality .

Keywords: forward aware factor(FAF), Energy balance, Routing, Wireless sensor networks(WSNs).

[1]. Abd El-kader S M and Eissa H S, Mohammed M. Zahra (2011) 'An Optimized Energy-aware Routing Protocol for Wireless Sensor Network Egyptian Informatics Journal' vol 34 no 12 pp.61–72
[2]. Abusaimeh H and Yang H (2009) ' Dynamic Cluster Head for Lifetime Efficiency in WSN International Journal of Automation and Computing' vol 67 no 4 pp.48-54.
[3]. Attea B A and Khalil E A (2011) 'Energy-aware evolutionary routing protocol for dynamic clustering of wireless sensor networks' vol 122 no.1 pp.104-124
[4]. Awan I and Bajaber T (2011) 'Adaptive decentralized re-clustering protocol for wireless sensor Networks : Journal of Computer and System Sciences' vol 77 no 2 pp. 282–292
[5]. Balakrishnan H, Chandrakasan A, Heinzelman W R(2000) 'Energy Efficient Communication Protocol for Wireless Microsensor Networks. IEEE. Published in the Proceedings of the Hawaii International Conference on System Sciences' vol 81 no 1 pp.41-47.
[6]. Boavida F, Camilo C, Carreto J and Silva S (2006) ' An Energy-Efficient Ant-Based Routing Algorithm for Wireless Sensor Networks' vol 35 no 9 pp.879-885

Abstract: Currently there is a plethora of social networks available and new ones are being introduced continuously. The information originate in these, range from information the users share to that generated from the interaction of the user with the system. Information from a single social network may be abundant enough to generate rich user profiles, which can be used for personalization services, recommendation services, etc. There is however an advantage in merging information from multiple information sources, to create richer user profiles. In this project we propose a peer to peer architecture to provide a fully decentralized system to generate and maintain distributed user models. Each peer in the system is made up of tribes for content replication among intended content consumers and serves it using low-cost network connections. Each peer in the system acts as a standalone user model; it extracts and translates information into pre-defined templates, which are used to ensure interoperability when communicating with other peers, through an internal server. A performance analysis for transmission rates and delays is therefore conducted. MobiTribe saves 76% of the uplink and 46% of the downlink cellular bandwidth compared to current widely used centralized server based content sharing architectures. Keywords: peer-to-peer, content sharing

[1]. Crawdad [Online]. Available: http://crawdad.cs.dartmouth.edu
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[3]. A. Balasubramanian, R. Mahajan, and A. Venkataramani, "Augmenting mobile 3G using WiFi," in Proc. MobiSys, San Francisco, CA, USA, 2010, pp. 209–222.
[4]. N. Balasubramanian, A. Balasubramanian, and A. Venkataramani, "Energy consumption in mobile phones: A measurement study and implications for network applications," in Proc. 9th ACM SIGCOMM IMC 2009, Chicago, IL, USA, pp. 280–293.
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Abstract: Energy is a heart of ad hoc networks. The lifetime of the network depends on the durability of the mobile node's battery power. Many energy conserving schemes are used to improve the energy efficiency and prolong the operational time of the mobile stations. Among these schemes Quorum based power saving protocol provides better energy conservation. In existing QPS the cycle length is identical to all the stations. The amount of conserved energy also low. To overcome this we propose a new scheme called Hyper quorum system (HQS). In this it uses an arbitrary cycle length for stations to maximize the energy efficiency and reduce the overall delay. Simulation results showed that the benefits of HQS over existing QPS.
Keywords: Ad hoc network, DCF, MAC, Power Saving Mode, Quorum systems

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Abstract: Technology scaling has enabled us to integrate both memory and logic circuits on a single chip. However, the performance of embedded memory and its peripheral circuits can adversely affect the speed and power of the overall system. Sense amplifier is one of the important peripheral circuits in the memory as it strongly influences the memory access times. It retrieves the stored data from the memory array by amplifying the small differential signal on the bit lines. Therefore, the power dissipated within the on-chip caches, both active and standby will become dominant parts of the total power consumption of the chip. In view of the above, there apparent urgency to address the power dissipation of chip. The main objective of this paper is the design of Low Power Sense Amplifier. For lowering the power dissipation three techniques are used voltage scaling, half Vdd precharge circuits and VTCMOS. The most efficient way of reducing power dissipation is by scaling down the power supply voltage.

Keywords: Low Power Technology, Tanner Tools

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Abstract: This paper proposes the concept of compact hexagonal fractal multi-band antenna. By using the compact hexagonal fractal antenna it is possible to achieve the directional pattern with high gain. The coaxial feeding technique is used for designing the antenna. This hexagonal antenna is used for different wireless application. The working frequency band covers a large number of wireless communication applications including GPS (1.6GHz), Bluetooth (2.4 GHz) & WLAN (3.6GHz).With hexagonal structure it is possible to configure the multi-band frequency with high gain. Antenna design has been designed and analyzed by using the software Ansoft's HFSS. Comparative results of simulated parameters like gain, return loss, directivity, VSWR, which had presented in this paper. Keywords: Directivity, Fractal antenna, gain, HFSS, microstrip, multi band Frequency.).

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[2]. Muhammad Waqas1, Zubair Ahmed2, Mojeeb Bin Ihsan "Multiband Sierpinski Fractal Antenna" 2009 IEEE
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[6]. Rahul Batra, P. L. Zade, DipikaSagne, "Design and Implementation of Sierpinski Carpet Fractal Antenna for Wireless Communication". International Journal of Scientific Research Engineering &Technology (IJSRET) Volume 1 Issue3 pp 043-047 July 2012.