{"title":"A New Public Key Multi-Message Dynamic Signcryption (PK-MM-DS) Scheme for Cryptographic Transmission","authors":"H. Elkamchouchi, A. Emarah, E. Hagras","doi":"10.1109/NRSC.2007.371399","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371399","url":null,"abstract":"In this paper, a new efficient public key multi-message dynamic signcryption (PK-MM-DS) scheme for cryptographic transmission has been proposed. The proposed scheme is simultaneously fulfills the multiple messages in a logical single step by using a random multi-key generator which introduce a great deal of redundancy. The dynamic structure in the proposed scheme has been achieved by using the new secure hash dynamic structure algorithm (SHDSA) which has been recently developed. The security level in PK-MM-DS is based on the dynamic parameter of the SHDSA. The most significant advantage of the proposed algorithm over the signcryption schemes lies in the dramatic reduction of computational time, communication overhead and increasing the security level. It has an efficient computation time and communication overhead compared with Zheng signcryption scheme. More specifically, it has been shown that for the minimum security parameters recommended for use in current practice, the proposed scheme costs 41.7% less in communication overhead and 75% less in average computation cost than does Zheng signcryption scheme. The saving in cost grows proportionally to the number of the signcrypted message which satisfies a high level of security and minimum costs.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124977254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Modified E-Shaped Microstrip Antenna for Ultra Wideband Wireless Systems","authors":"Maher M. Abd-Elrazzak, Ibrahim S. Al-Nomay","doi":"10.1109/NRSC.2007.371347","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371347","url":null,"abstract":"In this paper, the analysis of a modified E-shaped patch antenna is presented. The purpose of the modification over the original E-shaped structure is to accommodate the operating frequency band and signal bandwidth requirements of the Ultra Wideband (UWB) wireless system. Simulation results show that the modified R-shaped has fulfill the frequency band and signal bandwidth requirements of the UWB system. A resonance frequency of 3.5 GHz and signal bandwidth of 29.3% is achieved for the presented structure. The analysis of the proposed antenna has been done using the finite difference time domain (FDTD) with Perfect Matched layer (PML) approach. Results have been compared with published data and good agreements are found.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131589320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Directional Coupler as an Electro-Optically Controlled Wavelength Division Demultiplexer","authors":"A. Zaghloul","doi":"10.1109/NRSC.2007.371406","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371406","url":null,"abstract":"The number of passbands of the bandpass filter increases with the increasing of the difference of the propagation constants of the three waveguides of the directional coupler (i.e. electro-optically controlled). The allowed wavelengths (signals) which can be transmitted through the coupler's waveguides (wavelength division demultiplexer, WDDM) become very large with asymmetric electrooptic materials. Then the problem of length of WDDM is treated by electro-optical control. In case of symmetric electrooptic materials of the three waveguides, the maximum number of the allowed signals occurrs with BaTiO3. BaTiO3, LiNbO3 and BaTiO3 are the best asymmetric materials. The design procedure of WDDM is done. The numerical results with five different electrooptic materials are presented as design curves.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134186697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optimization of an Antipodal Vivaldi Antenna using Synthesis Neural Networks and a Novel Genetic Algorithms Approach","authors":"A. Elsherbini, A. Kamel, H. Elhennawy","doi":"10.1109/NRSC.2007.371355","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371355","url":null,"abstract":"Two global optimization techniques, applicable for the optimization of several antennas and microwave components, are presented. The two techniques are explained together with a sample application, which is the optimization of an antipodal Vivaldi antenna. The first technique was found useful in optimizing the design aspects whose physical behavior is known, whereas the second was better for optimizing the design aspects for which the response behavior is unknown, but an adequate performance metric can be defined. The two methods are compared; the limitations and advantages of each method arc presented together with some other optimization techniques.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115689316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An Efficient Computational Approach in the Matrix Pencil Method to Find One Dimensional and Two Dimensional Direction of Arrival","authors":"H. Elkamchouchi, M. Omar","doi":"10.1109/NRSC.2007.371348","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371348","url":null,"abstract":"The problem of estimating the direction of arrival (DoA) of the various sources impinging on a phased array has received considerable attention, in many fields including radar, sonar, radio astronomy and mobile communications. A very efficient computational procedure in the Matrix Pencil (MP) method to compute the one dimensional direction of arrival (1D-DoA) of the signals impinging on the linear array operating in the presence of undesired electromagnetic effects is given in this paper. This procedure reduces the complexity of the computation significantly by using a unitary matrix transformation. This technique is applied directly to the corrected data by applying the transformation matrix to compensate the undesired electromagnetic effects such as mutual coupling between the antenna elements without forming a covariance matrix. A unitary transform can convert the complex matrix to a real matrix along with their eigenvectors and thereby reducing the computational cost at least by a factor of four. Finally, a new technique based on the above procedure is proposed and applied to a planar array to find the two dimensional direction of arrival (2D-DoA). Limited numerical examples are presented to illustrate the performance and accuracy of the proposed techniques.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114831851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Performance Analysis of OFDM with M-ary Modulation in Sum of Frequency-Selective Arbitrary Nakagami-m Fading Channels","authors":"A. F. Alnahhal, M. Khedr, R. Abdelrassoul","doi":"10.1109/NRSC.2007.371383","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371383","url":null,"abstract":"Error rates of orthogonal frequency-division multiplexing (OFDM) signals using M-ary modulation in multipath slow fading Nakagami-m fading channel are considered. The exact probability density function of a sum of Nakagami-m random phase vector is used to derive a closed-form expression for the error rates of OFDM signals with arbitrary fading index m. This is done using the well-known moment generating function (MGF) analysis approach and in terms of the confluent hypergeometric function. For two-tap channel with finite value of Nakagami-m fading parameter, our analysis and numerical results show that error-rate performance of OFDM signal is similar to that of single carrier signal transmitted over a Rayleigh fading channel. Furthermore, our analysis shows that in a frequency-selective channel, depending on the number of channel taps, the error-rate performance does not necessarily improve with increasing Nakagami-m fading parameters.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116253198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Performance Enhancement of the Multi-Modulus Algorithm Based Adaptive Antenna Arrays Using Additional Constraints","authors":"S. El-Khamy, D. Abd-Elaziz, R. Korayem","doi":"10.1109/NRSC.2007.371343","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371343","url":null,"abstract":"The linearly constrained minimum variance (LCMV) algorithm fails to capture the signal if coherent copies (multipath signals) impinge on the array at the same time with the signal. The constant modulus algorithm (CMA) and the multi-modulus algorithm (MMA) techniques solved this problem with the disadvantage of more complicated behavior and the violation of some constraints about null directions staled by the initial weights. This is the main point of interest of the new algorithms proposed in this paper. The proposed algorithms in this paper, namely, the linearly constrained CMA (LCCMA) and linearly constrained MMA (LCMMA) solved this problem and arc able to hold the initial constraints about deep nulls until the adaptation is finished. This property has been successfully used to improve the performance of the MMA algorithm to capture very high signal constellations in multipath and interference environment without having to use the more complicated generalized MMA (GMMA).","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129206148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Decision Tree Approach to Estimate User Location in WLAN Based on Location Fingerprinting","authors":"O. Badawy, Mesbahul Hasan","doi":"10.1109/NRSC.2007.371395","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371395","url":null,"abstract":"The estimation of user location using modern communication technology like WLAN based on radio signal strength, is a recent interesting area. There are many indoor positioning techniques to estimate user location; location fingerprinting, time of arrival (TOA), time difference of arrival (TDOA), angle of arrival (ADA) and others. LocationfFingerprinting technique is more suitable than other techniques, because TOA, TDOA or AOA is suffer from non-line-of sight error and multi path, especially in urban and suburban area. In this paper we study the fingerprinting technique using neural network, nearest neighbor and decision tree to estimate the location. The results of the experiment show that using DT technique is the best to estimate the location of the user.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116793055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Nasr, S. Elkaffas, T. A. El-Tobely, A. Ragheb, E. Abd El-Samie
{"title":"An Integrated Image Fusion Technique for Boosting the Quality of Noisy Remote Sensing Images","authors":"M. Nasr, S. Elkaffas, T. A. El-Tobely, A. Ragheb, E. Abd El-Samie","doi":"10.1109/NRSC.2007.371370","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371370","url":null,"abstract":"To better identify the objects in remote sensing images, the muItispectral images with high spectral resolution and low spatial resolution, and the panchromatic images with high spatial resolution and low spectral resolution need to be fused. Many fusion techniques are discussed in the recent years to obtain images with high spectral resolution and also high spatial resolution. In this paper an image fusion technique, based on integrating both the intensity-hlue-saturation (IHS) and the discrete wavelet frame transform (DWFT), is proposed for boosting the quality of remote sensing images. A panchromatic and multispectral image from Landsat-7(ETM+) satellite has been fused using this new approach. Experimental results show that the proposed technique improves the spectral and spatial qualities of the fused images. Moreover, when this technique is applied to noisy and de-noised remote sensing images it can preserve the quality of the fused images. Comparison analyses between different fusion techniques are also presented and show that the proposed technique outperforms the other techniques.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"39 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114116110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of Stacked Rectangular Microstrip Antenna","authors":"I.K. Moussa, D. Mohamed, I. Badran","doi":"10.1109/NRSC.2007.371357","DOIUrl":"https://doi.org/10.1109/NRSC.2007.371357","url":null,"abstract":"A stacked microstrip antenna with C-type feed is designed in order to enhance the bandwidth. The effect of the various parameters, such as the rotation feed angle (thetas), the variations of relative permittivity of parasitic patch (epsivr2), the distance of the feed point from the center (r), and the separation between two stacked patches (h2), have been discussed. Some designs give a good return loss under -40 dB and wide VSWR bandwidth, such as case#2 with epsivr2=4.26, case#4 with r=6.2 mm, case#5 with h2=6.8 mm, case#1,and case#2 with h2=8.2 mm. The simulated data are obtained using the IE3D simulator with method of moments (MoM) commercial code. An infinite ground plane has been considered for simulations; however, and due to a software constraint, substrate dimensions are infinite.","PeriodicalId":177282,"journal":{"name":"2007 National Radio Science Conference","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125377611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}