Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396)最新文献_第4页

Influence of carrier-temperature gradients on the transport of hot carriers across semiconductor junctions 载流子温度梯度对热载流子通过半导体结输运的影响

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838964

M. El-Saba

引用次数: 1

Generation of an approximate TE electromagnetic X-wave in free space and in a planar layered medium using a finite array of electric dipoles 利用有限电偶极子阵列在自由空间和平面层状介质中产生近似TE电磁x波

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838847

A. Attiya, E. El-Diwany, A. Shaarawi

引用次数: 0

Restoration of multichannel images with limited a priori information using multichannel parallel-like adaptive filters 利用多通道类平行自适应滤波器恢复有限先验信息的多通道图像

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838947

M. Hadhoud

{"title":"Restoration of multichannel images with limited a priori information using multichannel parallel-like adaptive filters","authors":"M. Hadhoud","doi":"10.1109/NRSC.2000.838947","DOIUrl":"https://doi.org/10.1109/NRSC.2000.838947","url":null,"abstract":"We introduce a heuristic method for adaptive multichannel restoration of degraded multispectral images when there is limited knowledge about the undegraded images and the noise. The proposed structure aims at reversing the action of the blur function on the image. The system uses number of channels equal to the number of multispectral images L. Each channel consists of L subchannel structures of two parallel adaptive filters with different cutoff frequencies and different DC (zero frequency) gain. The overall structure in each subchannel is equivalent to a filter, which has a combined LP-BP like characteristics. The resulting system has unity gain at the DC, which preserves the image local characteristics. The filter has high gain in the middle (band pass) frequency range, which produces an output image with restored edges. The filter structure gain at the high frequency range is small which reduces the high frequency noise. The adaptive filters are considered for the implementation of the proposed method. This is because they have many desirable properties and able to track the variations in the image characteristics. Multiple channel restoration results are presented and compared with single channel restoration. The results show that the proposed multiple channel restoration is very effective in restoring image details and reduces the noise amplification. Also the fine details are enhanced and preserved.","PeriodicalId":211510,"journal":{"name":"Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115868536","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

Analysis of circuits containing nonlinear elements using neural networks and genetic algorithm 用神经网络和遗传算法分析含有非线性元件的电路

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838927

M. Yakout, A. AbdelFattah, A.S. Elbazz

引用次数: 4

Chiral absorbing material 手性吸收材料

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838840

A. Allam

引用次数: 4

Modelling and analysis of coplanar waveguide for LiNbO/sub 3/ optical modulators LiNbO/ sub3 /光调制器共面波导的建模与分析

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838907

A. Abou El-fadl, T. E. Taha, A.A. Aboul-Enien

引用次数: 0

Design of radiation hard CMOS APS image sensors for space applications 空间应用抗辐射硬CMOS APS图像传感器的设计

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838967

E. El-Sayed

{"title":"Design of radiation hard CMOS APS image sensors for space applications","authors":"E. El-Sayed","doi":"10.1109/NRSC.2000.838967","DOIUrl":"https://doi.org/10.1109/NRSC.2000.838967","url":null,"abstract":"The overall objective the research work described in this paper was to design a radiation hard CMOS active pixel sensor (APS), which is intended for use in imaging systems flown on future NASA space missions in the era of ever decreasing mass and power budgets. The radiation hard designs of essential circuits required to enable the design of an experimental radiation hard CMOS APS image sensor are described. The completed design of a radiation hard CMOS APS image sensor is presented as well. The database of this design has been submitted to a mask house for a mask set generation and then fabrication. Plans for characterizing the chips after fabrication are currently being devised. This research work concludes that radiation hard CMOS APS image sensors are attainable. The combination of employing physical design techniques and a deep submicron standard CMOS fabrication process provides the path to radiation hard CMOS APS image sensors. Utilizing commercial standard CMOS fabrication processes to realize radiation hard image sensors makes economic sense. The cost element associated with these standard processes is less (by at least a factor of two) than the cost element associated with specialized radiation hard processes.","PeriodicalId":211510,"journal":{"name":"Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128109753","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

HF electric field effect on Buneman's instability in a relativistic plasma waveguide 高频电场对相对论等离子体波导中布曼不稳定性的影响

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838973

K. El-Shorbagy

{"title":"HF electric field effect on Buneman's instability in a relativistic plasma waveguide","authors":"K. El-Shorbagy","doi":"10.1109/NRSC.2000.838973","DOIUrl":"https://doi.org/10.1109/NRSC.2000.838973","url":null,"abstract":"The stabilizing effect of a strong HF (pump) electrical field on the Buneman instability in a plane relativistic plasma waveguide is investigated. A new mathematical technique, the separation method, is applied to the two-fluid plasma model to separate the equations, which describe the system, into two parts: temporal and space parts. The temporal (dynamical) part enables us to determine the frequencies and growth rates of unstable modes; this part within the redefinition of natural frequencies coincides with the system describing HF suppression of the Buneman instability in a uniform unbounded plasma. Natural frequencies of oscillations and spatial distribution of the amplitude of the self-consistent electrical field are determined from the solution of a boundary-value problem (space part) taking into account the specific spatial distribution of plasma density. Plasma electrons are considered to have a relativistic velocity. It is shown that the growth rate instability in the relativistic plasma has been reduced compared to the nonrelativistic plasma. Also, it is found that the relativistic plasma electrons have not affected the solution of the space part of the problem.","PeriodicalId":211510,"journal":{"name":"Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396)","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127056781","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: 12

Adaptive space-time processing for interference suppression in phased array radar systems. I. Search radar 相控阵雷达干扰抑制的自适应时空处理。一、搜索雷达

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838845

H. Ghouz, F. Elghany, M.M. Qutb

{"title":"Adaptive space-time processing for interference suppression in phased array radar systems. I. Search radar","authors":"H. Ghouz, F. Elghany, M.M. Qutb","doi":"10.1109/NRSC.2000.838845","DOIUrl":"https://doi.org/10.1109/NRSC.2000.838845","url":null,"abstract":"This paper presents an adaptive technique of filtering to suppress the interference in phased array search radar systems. This interference includes noise, clutter, and jamming signals. Unlike the time processing techniques, our filtering process is based upon the target Doppler shift as well as the interference spatial distribution to suppress adaptively the undesired signals. This can be achieved by estimating the spatial covariance matrix of the interference using the direct matrix inversion (DMI) algorithm to compute the optimum weights of the adaptive filter. This technique of filtering is referred to as the adaptive coherent space-time (ACST) filter. A computer code has been developed to simulate the adaptive space-time filtering process. The objective is to investigate and evaluate in detail the performance of the adaptive filter under different interference environments including total intercepted power, statistical model, type and spatial distribution. The results of our simulation show that with moderate filter complexity an appreciable improvement in the signal to interference plus noise ratio at the filter's output \"SINR\" is obtained. In addition, the filter's performance is very sensitive to the interference type which has a direction either coincident with or close to the desired signal direction. The adaptive filter presented in this paper is an attractive and robust solution for solving the detection problem of low radar target cross section in an interference background such as stealth aircraft.","PeriodicalId":211510,"journal":{"name":"Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127230966","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: 2

Hybrid adaptive motion search with wavelet/wavelet packet based motion residual video coding 基于运动残差视频编码的小波/小波包混合自适应运动搜索

Proceedings of the Seventeenth National Radio Science Conference. 17th NRSC'2000 (IEEE Cat. No.00EX396) Pub Date : 2000-02-22 DOI: 10.1109/NRSC.2000.838923

E. Youssef, E. Sabry, M. Khedr

引用次数: 3