iosr-JECE   Volume-9 ~ Issue-1 ~ Jan-Feb 2014

Abstract: Smart antenna is the most efficient leading innovation for maximum capacity and improved quality and coverage. Efficient utilization of limited radio frequency spectrum is only possible to use smart/adaptive antenna system. Smart antenna radiates not only narrow beam towards desired users exploiting signal processing capability but also places null towards interferers, thus optimizing the signal quality and enhancing capacity. Smart antennas exploit space diversity to help provide high data rates, increased channel capacity, and improved quality of service. A systematic comparison of the performance of different Adaptive Algorithms for beam forming for Smart Antenna System has been extensively studied in this research work. Simulation results revealed that training sequence algorithms like Recursive Least Squares (RLS) and Least Mean Squares (LMS) are best for beam forming (to form main lobes) towards desired user but they have limitations towards interference rejection. While Constant Modulus Algorithm (CMA) has satisfactory response towards beam forming and it gives better outcome for interference rejection, but Bit Error Rate (BER) is maximum in case of single antenna element in CMA. The effect of changing step size for LMS algorithm has also been studied.
Index Terms: Adaptive antenna systems, Constant modulus algorithm, Least mean squares, Smart antenna.

[1 ] Zhang, Magdy F. Iskander, Zhengqing Yun and Anders Høst-Madsen, "Hybrid Smart Antenna System Using Directional Elements Performance Analysis in Flat Rayleigh Fading" IEEE Trans. On Antennas and Propagation. vol. 51, no. 10, pp. 1673–1694, October 2003.
[2] K.R. Shankar Kumar and T.Gunasekaran, "Performan Analysis of Adaptive Beamforming Algorithms for Microstrip Smart Antennas," International Journal of Computing Science and Communication Technologies vol. 2, no. 1, pp. 2006–2013, july. 2009.
[3] Debashis Panigrahi, Abhinav Garg & Ravi S. Verma. "A STUDY OF BEAMFORMING TECHNIQUES AND THEIR BLIND APPROACH"
[4] S.C.Upadhyay, P. M. Mainkar," Adaptive Array Beamforming using LMS Algorithm"International Journal of Engineering Research & Technology (IJERT) Vol. 2 Issue 1, Januaryr- 2013.
[5] "Investigation of Adaptive Beamforming Algorithm for Smart Antenna System to Improve the Effect of Angle Separation" by Seifu Girma.

Paper Type	:	Research Paper
Title	:	Optical Flow Based Multiple Object Detection and Tracking System in Static and Dynamic Environment
Country	:	India
Authors	:	Smitha Gayathri D. || Dattatreya K. A.
	:	10.9790/2834-09150916

Abstract: Estimation and tracking of multiple moving objects in a dynamic environment is a challenging task in computer vision. It demands real-time computation with reliable accuracy on embedded processors. This project focuses on the identification, analysis and implementation of suitable single and multiple moving object detection and tracking algorithm which makes use of spatiotemporal information. In this Thesis, the spatiotemporal information is obtained using Optic Flow computation. Optical Flow is a vector field which gives both magnitude and direction of the pixel movements with respect to consecutive frames. Horn and Schunck algorithm is used in this work for computation of Optical Flow vectors. Single and multiple objects based on the computed vectors are segmented using intensity based thresholding. Image enhancement techniques consisting of morphological operations and pixel connectivity are applied to enhance the segmented objects. The designed tracking algorithm is implemented MATLAB. The developed algorithm is first validated and its parameters tuned using real and virtual data with static background. For tracking in dynamic background the segmented objects are identified and the user is asked to choose one of the objects to track. A centroid based approach is used to track the chosen object.
Key Words: Optical Flow, Segmentation, Threshold and Centroid.

[1] Linda Shapiro and George Stockman, Computer Vision, Prentice Hall, Jan 2001
[2] Henry Schneiderman and Takeo Kanade, Object Detection Using the Statistics of Parts, International Journal of Computer Vision, Issue no: 56, pp. 151–177, 2004
[3] Hue C., Le Cadre J.-P and P. Perez, Tracking Multiple Objects With Particle Filtering, IEEE transactions on Aerospace and Electronic Systems, Vol. 38, pp. 791-812, Dec. 10. 2002.
[4] L. Li, W. Huang, I. Y. H. Gu, and Q. Tian, Foreground object detectionin changing background based on color co-occurrence statistics, In Proc. IEEE Workshop on Applications of Computer Vision, 2002.
[5] C. Stauffer and W. E. L. Grimson, Adaptive background mixture models for real-time tracking, In Proc. IEEE Conf. Computer Vision and Pattern Recognition, 1999.

Paper Type	:	Research Paper
Title	:	Radio Wave Propagation
Country	:	India
Authors	:	Vatsal Modi
	:	10.9790/2834-09151719

Abstract: This thesis deals with Radio Wave Propagation in environments where the propagation is severely influenced by surrounding objects, mainly walls and other building structures. As an introduction, a brief description is given on propagation terms like loss, delay and dispersion along with system functions relevant for the topic. The focus is then placed on propagation from an outdoor transmitter to an indoor receiver at frequency bands aimed at personal communications and wireless local area networks. Penetration loss is measured at 1.8 and 5.8 GHz for various small scale wall and window structures. Empirical models have been evaluated for the dependence on incidence angle in order to provide a simple yet accurate model for the loss.

[1]. H. P. Westman: Reference Data for Radio Engineers, Fifth Edition, 1968, Howard W. Sams and Company.
[2]. Demetrius T,Paris and Frank Kenneth Hurd: Basic Electromagnetic Theory, McGraw Hill Book Company,New York (United States Of America) 1969.
[3]. Radiowave Propagation, edited by M.Hall and L.Barclay, published by Peter Peregrinus Ltd., (1989).
[4]. Lucien Boithais: Radio Wave Propagation, McGraw Hill Book Company,New York (United States Of America).

Paper Type	:	Research Paper
Title	:	Objects Counting on Mobile Platform in Dusty Environment Through Load Measurement
Country	:	India
Authors	:	Moiz Chasmai || Ansari AN || Arun Barde || Ganesh Mutkule
	:	10.9790/2834-09152025

Abstract: In applications where the electronic systems are required to be used in mobile and dusty environmental conditions, the performance of systems becomes critical with respect to selection of sensors as they need to be done carefully. In such harsh conditions the main objective and challenge is to select suitable sensors and mount the sensors such that high degree of accuracy and reliability is achieved. Our application required to count the number of objects at any instant on a transverse platform mounted on a vehicle that encounters dusty environmental conditions. In our application, we have used load cells with proper mounting to address the specific end use conditions. In this paper we have discussed the selection of sensor, mounting design, related electronic circuitry and its testing. The tests were conducted to count the number of objects on transverse platform through the load measurement. The results show that the design is robust and can work in a dusty and mobile environment with high accuracy.
Keywords: Load cell, Sensors, Strain gauge, Transverse platform.

[1] VPG transducers, Doc No 11866, Rev 21 Feb 2012, pg. no. 1,2.
[2] Guide for load cells, Welmec 2.4, issue 2, Aug 2001, pg. no. 9, 10.
[3] HAR RY E. LOCK ERYMEE, What Puts the 'Quality' Into High Quality Strain Gage Load Cells?, White paper.
[4] Load Cells: A Primer on the Design and Use of Strain Gage Force Sensors, pg no 11.
[5] Introduction to type of sensors, ilabs, www.ilabsindia.com, pg 1-10.

Paper Type	:	Research Paper
Title	:	Ultra Wide Band LPDA Design using HFSS
Country	:	India
Authors	:	Rakhi Dua || Dr. Arti Vaish
	:	10.9790/2834-09152627

Abstract: This paper describes the development of LPDA using HFSS. Log Periodic Antennas are antennas with high gain, large bandwidth, large front to back ratio and low cost. These antennas are quite convenient for commercial broadcast and radio signal detection. The UWB LPDA antenna is slightly modified to cover 1GHz to 4GHz bandwidth. The radiation patterns of sum and differential modes show good gain and null depth in the end-fire direction, respectively. The performance of the designed antenna is verified by finite integration and finite element method comparisons. The design of LPDA is reduced to attain better impedance matching.

Keywords: LPDA,HFSS,UWB

[1] F. P. Casares-Miranda, C. Camacho-Penalosa, and C. Caloz, "High-gain active composite right/left-handed leaky-wave antenna," IEEE Trans. Antennas Propag., pp. 22292–2300, Aug. 2006.
[2] O. Siddiqui, M. Mojahedi, and G. Eleftheriades, "Periodically loaded transmission line with effective negative refractive index and negative group velocity,"IEEE Trans. Antenna Propag., pp. 2619–2625, Oct. 2003.
[3] A. Erentok and R. W. Ziolkowski, "A hybrid optimization method to analyze metamaterial-based electrically small antennas," IEEE Trans. Antennas and Propagation, pp. 731–741, Mar. 2007.
[4] F. P. Casares-Miranda, C. Camacho-Penalosa, and C. Caloz, "High-gain active composite right/left-handed leaky-wave antenna," IEEE Trans. Antennas Propag., pp. 2292–2300, Aug. 2006.
[5] S.-S. Oh and L. Shafai, "Compensated circuit with characteristics of lossless
[6] Double negative materials and its application to array atennas," IET Microw.Antenna Propag., Special Issue on Metamaterials LHM, pp. 29–38, Nov. 2007.
[7] D. Pozar, Microwave Engineering, 3rd ed. Hoboken, NJ: John Wiley & Sons, 2004.

Paper Type	:	Research Paper
Title	:	Low Complexity Channel Estimation for MC-CDMA System Based Chaos under Fast Multipath Channel
Country	:	Iraq
Authors	:	Maha George Zia
	:	10.9790/2834-09152835

Abstract:Based on interpolation methods, a low complexity channel estimation method for MC-CDMA system based chaos under fast fading multipath channel is proposed.Different interpolation methods are used; Linear interpolation (LI), cubic spline interpolation (CSI), and piecewise cubic Hermite interpolation (PCHI). The multi-carrier scheme is established by using a chaotic generator with different initial conditions, while the pilots are established using another chaotic generator with another different initial conditions. The proposed channel estimator without and with interpolation methods for single user and multiusers is tested under fast frequency selective Rayleigh fading channel. Simulation results demonstrate that the channel estimation of MC-CDMA system based chaos using interpolation methods and when the pilots are chaos signal too,

[1] S. Hara and R. Prasad," Design and performance of Multicarrier CDMA system in frequency-selective Rayleigh fading channels," IEEE Trans. Vehicle. Technology, vol. 48, no. 5, Sep. 1999, pp.1584-1595.
[2] U. Tureli, D. Kivanc and H. Liu," Channel estimation for multicarrier CDMA," ICASSP 2000, 2000, pp. 2909-2912.
[3] S. Iraji, T. Sipila and J. Lilleberg ," Channel estimation and signal detection for MC-CDMA in multipath fading channels," The 14"' IEEE 2003 international Symposium on Personal lndoor and Mobile Radio Communication Proceedings, 2003, pp. 2286-2290.
[4] Trivedi and R. Gupta," Pilot Symbol Assisted Channel Estimation for Uplink MC-CDMA Systems using Parametric Channel Modeling," International Symposium on Communications and Information Technologies (ISCIT 2007), 2007, pp. 989-993.
[5] H. Tomeba, K. Takeda, F. Adachi," Pilot assisted channel estimation for MC-CDMA signal transmission using overlap FDE," ICCS 2008, 2008, pp. 1106 -1110.
[6] S. Coleri, M. Ergen, A. Puri, and A. Bahai," Channel Estimation Techniques Based on Pilot Arrangement in OFDM Systems," IEEE Trans. Broadcasting, vol. 48, no. 3, Sept. 2002, pp. 223-229,

Paper Type	:	Research Paper
Title	:	Noise Removal in Image Using LPG-PCA (Local Pixel Grouping-Principle Component Analysis) Algorithm
Country	:	India
Authors	:	G.Hari Priya || B.Venkatesh || A.Srivani || G.Sowmya || N.Rajasekhar
	:	10.9790/2834-0915364

Abstract: In this paper an effective algorithm for noise removal in an image is obtained by using PCA (principal component analysis) with LPG (Local Pixel Grouping). This technique ensures the preservation of image local structure. Here the pixels and its neighbors are treated as vector variables whose training samples are selected from local windows using block matching based LPG. This ensures only the similar samples are selected for the PCA transformation so that the desired local characteristics are only preserved with considerable noise reduction. The LPG –PCA algorithm is performed twice to enhance the quality of an image. The first iteration would remove the noise considerably and the second iteration would preserve the image features like edges etc.

[1] D.L Donoho ,de-noising by soft thresholding,IEEE Transactions on information theory 41(1995) 613-627.
[2] R.R Coifman, D.L Donoho, Translation-invariant-de-noising,sprinjer,Berlin Journal 1995
[3] M.K Michhack,I.Kozenstev,K.Ramachandran,P.Moulin Low complexity image de-noising based on statistical modelling of wavelet co-efficient, IEEE signal processing Letters 6(12) 1999,300-303.
[4] S.G Chang,B.Yu.M.Vetterli spatially adaptive wavelet thresholding with context modelling for image de-noising, IEEE transaction on image processing 9(9)2000,1522-1531
[5] A. Pizurica,W. Philips, Estimating the probability of the presence of a signal of interest in multi resolution single- and multiband image denoising, IEEE Transaction on Image Processing 15 (3) (2006) 654–665.
[6] J.L. Starck, E.J. Candes, D.L. Donoho, The curvelet transform for image denoising, IEEE Transaction on Image Processing 11 (6) (2002) 670–684.

Paper Type	:	Research Paper
Title	:	Security Issues With Implementation Of RSA And Proposed Dual Security Algorithm For Cloud Computing
Country	:	India
Authors	:	Uma Naik || V. C. Kotak
	:	10.9790/2834-09154347

Abstract:The concept of data storage allowed to think us on security algorithms to get the relevant data sent and received without any mis-transit in between. For this related security algorithms are existing for ensuring the security of data been encrypted and decrypted. The basic RSA algorithm is been implemented and based on the same further dual security algorithms are proposed. Further expansion of basic algorithm based on security fruitful levels of security algorithms can be implemented.

[1] Cloud Security and Privacy, An Enterprise Perspective - Tim Mather, Subra Kumaraswamy
[2] Cloud Computing - Web Based Applications That Change the Way You Work and Collaborate Online - Michael Miller
[3] An Improved RSA Encryption Algorithm For Cloud Computing Environments : Two Key Generation Encryption (2KGEA) – Ms Shubhra Saggar (Faculty, Guru Nanak Institute Of management, New Delhi), Dr. R.K.Datta (Director, M.E.R.I.T., New Delhi) (Research Paper on IJSWS).
[4] On Technical Security Issues In Cloud Computing, Meiko Jensen, Jorg Schwenk and Nils Gruschka, Luigi Lo Lacono, 2009 IEEE International Conference on Cloud Computing.
[5] Providing Privacy Preserving in Cloud Computing, Jian Wang, Yan Zhao, Shuo Jiang, Jiajin Le, 2009 International Conference on Test and Measurement.
[6] Chang, L, Ti ; Chin L; Chang, A.Y.; Chun J, C;(2010), " Information security issue of enterprises adopting the application of cloud computing", IEEE 2010 Sixth International Conference on Networked Computing and Advanced Information Management (NCM),pp 645, 16-18 Aug. 2010.

Paper Type	:	Research Paper
Title	:	Cooperative Spectrum Sensing In Cognitive Radio Networks Using Distinct Coding Techniques
Country	:	India
Authors	:	R.saranya || Mrs.K.Shanthalakshmi
	:	10.9790/2834-09154852

Abstract: This paper considers a multiuser spectrum sharing(SS) system operating in a Rayleigh fading environment and in which every node is equipped with multiple antennas. The system employs orthogonal space-time block coding at the secondary users. Under such a framework, the average capacity and error performance under a peak interference constraint are first analyzed.

[1] A.Ghasemi and E.S.Sousa, "Fundamental limits of spectrum-sharing in fading environments," IEEE Trans. Wireless Commun., vol.
6, no. 2, pp. 649–658, Feb. 2007.
[2] T. W. Ban, W. Choi, B. C. Jung, and D. K. Sung, "Multiuser diversity in a spectrum sharing system," IEEE Trans. Wireless
Commun., vol. 8, no. 1, pp. 102–106, Jan. 2009.
[3] H. A. Suraweera, P. J. Smith, and M. Shafi, "Capacity limits and performance analysis of cognitive radio with imperfect channel
knowledge," IEEE Trans. Veh. Technol., vol. 59, no. 4, pp. 1811–1822, May 2010.
[4] Z. Rezki and M.-S. Alouini, "Ergodic capacity of cognitive radio under imperfect channel state information," IEEE Trans. Veh.
Technol., vol. 61, no. 5, pp. 2108–2119, June 2012.
[5] R. Zhang and Y.-C. Liang, "Exploiting multi-antennas for opportunistic spectrum sharing in cognitive radio networks," IEEE J. Sel.
Areas Signal Process., vol. 2, no. 1, pp. 88–102, Feb. 2008.
[6] Y. Li and A. Nosratinia,"Capacity limits of multiuser multiantenna cognitive networks," IEEE Trans. Inf. Theory, vol. 58, no. 7, pp.
4493– 4508, July 2012.

Paper Type	:	Research Paper
Title	:	Adaptive Position Update for Geographic Routing In Mobile Ad Hoc Networks
Country	:	India
Authors	:	Gibin N.G || S. Ashok Kumar
	:	10.9790/2834-09155359

Abstract: In geographic routing, nodes need to maintain up-to-date positions of their immediate neighbours for making effectiveforwarding decisions. Periodic broadcasting of beacon packets that contain the geographic location coordinates of the nodes is apopular method used by most geographic routing protocols to maintain neighbour positions. We contend and demonstrate that periodicbeaconing regardless of the node mobility and traffic patterns in the network is not attractive from both update cost and routingperformance points of view.

[1]. Seungjoon Lee Bobby Bhattacharjee Suman Banerjee (2004), 'Efficient Geographic Routing in Multihop Wireless Networks' Technical Report CS-TR 4625, University of Maryland
[2]. Marc Heissenbuttel , Torsten Braun, Markus Walchli, Thomas Bernoulli (2005), 'Evaluating the limitations of and alternatives in beaconing' Tech. Rep. CS-2003-11
[3]. Young-Bae Ko and Nitin H. Vaidya (2006), 'Location-Aided Routing (LAR) in mobile ad hoc networks' Department of Computer Science, Texas A&M University, TX 77843-3112, USA
[4]. David B. Johnson David A. Maltz Josh Broch (2006)' DSR: The Dynamic Source Routing Protocol for Multi-Hop Wireless Ad Hoc Networks' Computer Science Department Carnegie Mellon University Pittsburgh, PA 15213-3891
[5]. Manel Guerrero Zapata (2007), 'Secure Ad hoc On-Demand Distance Vector Routing' Mobile Networks Laboratory Nokia Research Center
[6]. Marc Heissenbuttel, Torsten Braun, Thomas Bernoulli, Markus Walchli (2008) 'BLR: beacon-less routing algorithm for mobile ad hoc networks' Institute of Computer Science and Applied Mathematics, University of Bern, Bern, Switzerland

Paper Type	:	Research Paper
Title	:	The Contribution of ICT in Higher Education: a multifaceted approach
Country	:	India
Authors	:	Suhail Anwar || Dr. Sibichan K. Mathew
	:	10.9790/2834-09156063

Abstract: Information and Communication Technologies (ICTs), embrace many technologies that enable the users to receive and send information; making it convenient for the users to communicate or exchange information with others. ICT contributes in education in many ways such as: ICT as a collaborative tool, ICT as a tool to support traditional subjects, ICT as an administrative tool and many more. In teaching and learning, the use of ICT lies in putting in place ICT equipments and tools.

1]. Adam, S. (2001). Transnational Education Project. Report and Recommendations. Confederation of European Union Rectors' Conferences.
[2]. Annand, D. (1999) "The problem of computer conferencing for distance-based universities‟, Open Learning, 14 (3), 47-52, p. 20.
[3]. Ashish Kumar and Arun Kumar (2005),"IT based KM for Institutions of Higher Education A Need" , Paper published in A weekly Journal of Higher Education in India from Association of Indian Universities, New Delhi India Vol. 43, No. 30, July 25-31, 2005, pp. 4 – 9
[4]. available through http://www.hefce.ac.uk/pubs/HEFCE/2000/00_44.htm
[5]. Ben-Zion Barta., et.al. (1995)," Information Technology in Educational Management", Chapman and Hall, London.
[6]. Caroline Salerno (2009),"Administrator‟s Role in Technology Integration", Education World 2009.

Paper Type	:	Research Paper
Title	:	Design of a Non Fragile Optimal Controller Realization for Vehicle Suspension System for Different Road Profiles
Country	:	Pakistan
Authors	:	M. Abid Saeed, Niaz Ali, Muhammad Waqas, Anees ur rehman
	:	10.9790/2834-09156472

Abstract:This paper explains a suspension system of a vehicle which comprises of spring mass and damper. The main objective is to design a proper controller that can damp oscillations in order to provide safety, ease and comfort to passengers of vehicle during uneven road surface, bumps and small patches. To perform the desired task state space model of a quarter wheel vehicle suspension system is derived. The response of the system is simulated in MATLAB/SIMULINK. The open loop response showed that the derived model is stable. Different types of controllers are designed i.e. Linear Quadratic Regulator (LQR) and Observer based controller to analyze the system in closed loop. Both the controllers showed improved performance for different road profiles. It is observed and shown that observer based controller has better response than Linear Quadratic Regulator (LQR) controller.

[1]. Kowarska, Jarosáaw Skarbek, Krystian Kuczek and Tadeuszuhl, "Model-Based Engineering-Simulations Based Design of the Suspension of City Vehicle", AGH University of Science and Technology Department of Robotics and Mechatronics Mickiewicza, Poland, 2011.
[2]. Tadeo Armenta and Miguel Strefezza, "Controlling Vehicle Suspension Using an Optimal Fuzzy Controller", May 2007.
[3]. A.A.Aldair and W.J.Wang, "Design an Intelligent Controller for Full Vehicle Non Linear Active Suspension System", University of Sussex, UK, 2011.
[4]. Zhou J, Zhou D, Teo KL and Zhao G, "Nonlinear Optimal Feedback Control for Lunar Module Soft Landing", IEEE International Conference on Automation and Logistics, Shenyang, China, IEEE, 2009.
[5]. Nurhan GÜRSEL, İsmail Hakkı ALTAŞ and Levent GÜMÜŞEL, "Fuzzy Control of a VehicleSuspension System", "Intelligent Manufacturing Systems", Sakarya University, Department of Industrial Engineering, May 2006.
[6]. G.Verros and Natsiavas, "Design Optimization of Quarter Car Model with Passive and Semiactive Suspensions Under Random Road Excitation", Aristotle University, Greece, 2005.

Paper Type	:	Research Paper
Title	:	Implementation of Acoustic Communication in Under Water Using BPSK
Country	:	India
Authors	:	K.Saiteja, K.Rahul kumar, J.Vamsee kumar, M.Gaganviharvarma, CH.Gayatri
	:	10.9790/2834-09157381

Abstract: -The aim of the project is to make a prototype of acoustic communication system. The acoustic channel introduces some challenges in form of multipath propagation causing attenuation of the signals and Inter Symbol Interference (ISI). A coherent underwater acoustic communication system must deal with the inter symbol interference caused by the time-varying, dispersive, shallow-water ocean environment. The system is characterized with high data rate and low bit error probability using BPSK modulation technique. This paper contains the time-reversal process to acoustic communications in order to improve data telemetry in the ocean. To combat the influence of the channel we used a linear adaptive equalizer. The code was implemented in MATLAB, using acoustic signals different intermediate outputs are simulated and modulation and demodulation of signals are obtained which are shown in this project.

[1] D. B. Kilfoyle and A. B. Baggeroer, "The state of the art in underwater acoustic telemetry," IEEE J. Ocean. Eng., vol. 25, no. 1, pp. 4–27, Jan.2000.
[2] A. Song, M. Badiey, H.-C. Song, W. S. Hodgkiss, M. B. Porter,and the KauaiEx Group, "Impact of ocean variability on coherentunderwater acoustic communications during the Kauai experiment(KauaiEx)," J. Acoust. Soc. Amer., vol. 123, no. 2, pp. 856–865,Feb. 2008.
[3] M. Badiey, B. G. Katsnelson, J. F. Lynch, and S. Pereselkov, "Frequencydependence and intensity fluctuations due to shallow water internalwaves," J. Acoust. Soc. Amer., vol. 122, no. 2, pp. 747–760, Aug.2007.
[4] W. A. Kuperman, W. S. Hodgkiss, H. C. Song, T. Akal, C. Ferla, andD. R. Jackson, "Phase conjugation in the ocean: Experimental demonstrationof an acoustic time-reversal mirror," J. Acoust. Soc. Amer., vol.103, no. 1, pp. 25–40, Jan. 1998.
[5] G. F. Edelmann, T. Akal, W. S. Hodgkiss, S. Kim, W. A. Kuperman,and H. C. Song, "An initial demonstration of underwater acoustic communicationsusing time reversal," IEEE J. Ocean. Eng., vol. 31, no. 3,pp. 602–609, Jul. 2002.
[6] J. Gomes, A. Silva, and S. Jesus, "Adaptive spatial combining for passivetime-reversed communications," J. Acoust. Soc. Amer., vol. 124,no. 2, pp. 1038–1053, Aug. 2008.