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Proceedings of the Nineteenth National Radio Science Conference最新文献

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Multiband triple-patch microstrip antenna using 3D-FDTD method 三维时域有限差分法多波段三贴片微带天线
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022619
H. El Kamchouchi, Y. Madany
{"title":"Multiband triple-patch microstrip antenna using 3D-FDTD method","authors":"H. El Kamchouchi, Y. Madany","doi":"10.1109/NRSC.2002.1022619","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022619","url":null,"abstract":"A three-dimensional finite-difference time-domain (3D-FDTD) method is used to construct a new multiband operation of a microstrip patch antenna fed by single small strip. The antenna is constructed on Duroid substrate with relative permittivity 2.2. The FDTD method is used to calculate the radiation characteristics and input impedance of the antenna. The equivalence principle has been used to transform the time domain components of the near field to the frequency domain spherical components of the far field. The microstrip patch antenna has multiband frequencies at 2.8 GHz, 5.3 GHz, 7.75 GHz, and 10.23 GHz. Details of the antenna design and simulation results are presented and discussed.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123906546","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}
引用次数: 3
A robust protocol for authentication of mobile users 一种健壮的移动用户认证协议
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022630
N. El-Fishway, M. Nofal, A. Tadros
{"title":"A robust protocol for authentication of mobile users","authors":"N. El-Fishway, M. Nofal, A. Tadros","doi":"10.1109/NRSC.2002.1022630","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022630","url":null,"abstract":"In the next generation of mobile communication system users will be allowed to have a universal wireless access to multiple services. This implies the exchange of secret information with the home domain via the radio link as the radio path is more susceptible to eavesdropping. A new set of inter-domain security mechanism is needed to secure this information especially in the absence of a single central certification authority. Accordingly, the paper presents a new protocol for authentication of mobile users. The main features of the proposed protocol include the use of mutual authentication between the communicating entities, KrpytoKnight, and public key cryptography. These features will provide a high security level for the whole system.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121366249","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}
引用次数: 1
Modified batwing broadcasting antenna element 改进的蝙蝠翼广播天线元件
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022616
H. Elkamchouchi, M. El-Salam
{"title":"Modified batwing broadcasting antenna element","authors":"H. Elkamchouchi, M. El-Salam","doi":"10.1109/NRSC.2002.1022616","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022616","url":null,"abstract":"Modified batwing antenna element is a modified form of the conventional batwing array element used in broadcasting. The introduced design is based on the real shape of the wing bones, various trials have been carried out to get an approximate wing dimensions. The input characteristics and gain showed an enhanced response for the modified batwing to the conventional one with less dimensions. The method of moments is used to acquire all numerical analysis, the numerical electromagnetic code (NEC) is used to get numerical results. Radiation patterns for single, double, and quadruple element are shown for both antennas.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116578522","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}
引用次数: 0
New technique for perceptual wavelet based image watermarking 基于感知小波的图像水印新技术
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022877
S. El-Khamy, M. Lotfy, R. Sadek
{"title":"New technique for perceptual wavelet based image watermarking","authors":"S. El-Khamy, M. Lotfy, R. Sadek","doi":"10.1109/NRSC.2002.1022877","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022877","url":null,"abstract":"A new technique for the adaptive digital watermarking of still images is presented. The technique is based on the concepts of multiresolution wavelet fusion and the human vision system (HVS). We propose the use of a wavelet transform to embed signature information in different frequency bands of an image. This is done in a way that exploits the characteristics of HVS. The signature data in our case is another small image. The algorithm is robust to a variety of image processing operations. Simulation results show the superior performance of the technique.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123839161","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}
引用次数: 6
Adaptive hybrid DS/SFH spread-spectrum multiple access communications 自适应混合DS/SFH扩频多址通信
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022646
M. Abou Eldahab, M. Nassar, M. Fouad, A. El Monem Mokhtar
{"title":"Adaptive hybrid DS/SFH spread-spectrum multiple access communications","authors":"M. Abou Eldahab, M. Nassar, M. Fouad, A. El Monem Mokhtar","doi":"10.1109/NRSC.2002.1022646","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022646","url":null,"abstract":"The performance of coherent reception in asynchronous hybrid-direct/slow-frequency-hopped spread-spectrum multiple-access communications system operating through lognormal shadowing is investigated. System with BPSK and GMSK modulations and demodulations, as well as systems with adaptive filter (DFE) equalizer are examined and their probability of error is evaluated. Comparison of hybrid systems without and with adaptive equalizer using BPSK and GMSK modulation technique shows a considerable improvement in the performance of the system with adaptive equalizer and GMSK modulation outperform the BPSK modulation.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122831115","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}
引用次数: 1
Adaptive detection of the fetus ECG signal 胎儿心电信号的自适应检测
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022676
E. Soleit, M. Gadallah, A. Salah
{"title":"Adaptive detection of the fetus ECG signal","authors":"E. Soleit, M. Gadallah, A. Salah","doi":"10.1109/NRSC.2002.1022676","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022676","url":null,"abstract":"Extracting the fetal ECG signal from the composite maternal ECG signal obtained from abdominal leads is of great interest. The interfering maternal ECG signal is stronger than the fetal ECG one. Moreover, the background noise due to muscle activity and fetal motion strongly degrades the detection capability of the fetal ECG signal. A scheme based on the joint operation of an adaptive noise canceller (ANC) and an adaptive line enhancer (ALE) is proposed to detect the fetus ECG signal from the maternal ECG signal. The proposed scheme exhibits a great improvement in the output signal-to-noise ratio. Moreover, the heart rate of the detected fetal ECG signal is calculated and traced over a period of time to help in the discovery of fetal heart disease. Several cases for various weeks of the gestation period for pregnant women are analyzed.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124606029","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}
引用次数: 3
Micro-aneurysm detection using vessels removal and circular Hough transform 血管去除和圆形霍夫变换检测微动脉瘤
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022650
S. Abdelazeem
{"title":"Micro-aneurysm detection using vessels removal and circular Hough transform","authors":"S. Abdelazeem","doi":"10.1109/NRSC.2002.1022650","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022650","url":null,"abstract":"A digital image processing system has been developed to quantify the presence of micro-aneurysms in retinal fluorescein angiographic images. Automatic detection of micro-aneurysm in retinal angiographic images provides a valuable tool for early diagnosis of diabetic retinopathy. A novel approach for detecting micro-aneurysm in retinal angiographic images is presented. The proposed scheme is based on the removal of blood vessels from the image and then classifying whether all detected circular objects are micro-aneurysms. The new technique provides significant improvement in the detection of micro-aneurysm over other currently available schemes in the literature.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"142 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127556709","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}
引用次数: 65
Computational electromagnetic technique for broadband analysis of microstrip antennas 微带天线宽带分析的计算电磁技术
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022617
M. Mangoud, R. Abd‐Alhameed, P. Excell, M. Aboul-Dahab
{"title":"Computational electromagnetic technique for broadband analysis of microstrip antennas","authors":"M. Mangoud, R. Abd‐Alhameed, P. Excell, M. Aboul-Dahab","doi":"10.1109/NRSC.2002.1022617","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022617","url":null,"abstract":"Broadband analysis of a microstrip patch antenna on a finite substrate is investigated using the Finite Difference Time Domain (FDTD) method. The effects of varying the ground and dielectric size against the return loss at the input port and the far fields are discussed. Two different ways of feeding the antenna are addressed. The problem space size requirements of the FDTD method are presented.. A thin, wire code that,includes the wire radius of the coaxial feed cable is used. The frequency response of several microstrip patch antennas is analysed over wide bandwidths, using Gaussian pulses with a total bandwidth of 20 GHz. The results are in good agreement with measurements.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124520381","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}
引用次数: 0
Receivers for MACPM signals based upon the Laurent's representation 基于洛朗表示的MACPM信号接收器
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022633
E. Sabri, E. Youssef, S. Ikki
{"title":"Receivers for MACPM signals based upon the Laurent's representation","authors":"E. Sabri, E. Youssef, S. Ikki","doi":"10.1109/NRSC.2002.1022633","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022633","url":null,"abstract":"We develop optimum receivers for multi-amplitude continuous phase modulation (MACPM) signals. These receivers are based upon Laurent's representation of CPM as the sum of a finite number of pulse amplitude modulated signals. We also find the error performance for these receivers for high SNR.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130547152","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}
引用次数: 0
Temperature distributions in the human brain model during ultrasound hyperthermia 超声热疗期间人脑模型的温度分布
Proceedings of the Nineteenth National Radio Science Conference Pub Date : 2002-11-07 DOI: 10.1109/NRSC.2002.1022678
N. Ismail, A. T. Ibrahim
{"title":"Temperature distributions in the human brain model during ultrasound hyperthermia","authors":"N. Ismail, A. T. Ibrahim","doi":"10.1109/NRSC.2002.1022678","DOIUrl":"https://doi.org/10.1109/NRSC.2002.1022678","url":null,"abstract":"One of the important applications of ultrasound hyperthermia is temperature elevation at specified locations in the human brain. The ultrasound applicator used is a circular phased array surrounding the human head. The human head model is assumed to be two concentric spheres of skin and bone containing a hemisphere of brain. The single and multiple foci patterns of the ultrasound intensity generated by the circular phased array is investigated. The heating patterns, temperature distributions, corresponding to the absorption of ultrasound in the brain region is determined by solving the bioheat equation.","PeriodicalId":231600,"journal":{"name":"Proceedings of the Nineteenth National Radio Science Conference","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133141524","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}
引用次数: 0
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