Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462)最新文献_第6页

Finite difference time domain solutions for the dielectric resonator antenna problems with different feeding signals 具有不同馈电信号的介质谐振器天线问题的时域有限差分解

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929160

H. Elkamchouchi, Y.G. El-Kayar

引用次数: 2

CDMA performance improvement through bias reduction using optimized partial parallel interference cancellation factor 利用优化的部分并行干扰抵消因子减少偏置，提高CDMA性能

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929213

A. Fawzy, M. Riad

{"title":"CDMA performance improvement through bias reduction using optimized partial parallel interference cancellation factor","authors":"A. Fawzy, M. Riad","doi":"10.1109/NRSC.2001.929213","DOIUrl":"https://doi.org/10.1109/NRSC.2001.929213","url":null,"abstract":"In a CDMA system, the number of simultaneous users is a very important factor. So, a great number of researchers are interested in increasing the maximum available number of users for a given performance of a cellular system. To increase that number, multiple access interference (MAI) had to be cancelled. These cancellation techniques result in a bias term (BT) appearing in amplitude estimates after the cancellation process. The BT deviates the estimated values of amplitudes from their real mean, leading to a wrong decision. This paper introduces a new method to decrease the BT. Using the partial parallel interference cancellation (PPIC) factor, this factor is optimized against the bit error rate (BER). Also we show a comparison between BER of different types of sub-optimal receiver structures and PPIC with optimized factor F/sub g/. Finally, we compare the BER of 3-main categories of CDMA receivers: the conventional CDMA receiver, brute force cancellation with 2 stages and 3 stages, and PPIC with optimized factor F, with 2 stages and 3 stages. We can say that the use of PPIC with optimized factor is a very good technique to decrease the BER and increase the number of simultaneous users for a given system's parameters.","PeriodicalId":123517,"journal":{"name":"Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462)","volume":"542 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134198106","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

Simple closed-form solution for normalized current distribution and scattered field pattern for straight wires 直导线归一化电流分布和散射场图的简单封闭解

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929205

M. Fahmy, I. Eshrah, M. Khalaf

引用次数: 5

Nonlinear cumulant based adaptive filter for simultaneous removal of Gaussian and impulsive noises in images 基于非线性累积量的自适应滤波同时去除图像中的高斯噪声和脉冲噪声

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929235

H. M. Ibrahim, R. Gharieb, A. H. Ibrahim

引用次数: 1

Two-dimensional generalized sidelobe canceller (GSC) with partial adaptivity 具有部分自适应的二维广义旁瓣对消器

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929162

I. Salem, H. A. Hanafy, A. Moufid

引用次数: 4

Study of limitations on pixel size of very high resolution image sensors 超高分辨率图像传感器像素尺寸限制的研究

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929154

E. Eid

{"title":"Study of limitations on pixel size of very high resolution image sensors","authors":"E. Eid","doi":"10.1109/NRSC.2001.929154","DOIUrl":"https://doi.org/10.1109/NRSC.2001.929154","url":null,"abstract":"The employment of small pixel size is very crucial to the physical implementation of very high resolution CMOS APS image sensors. This is because of the restriction imposed by the required lithography method utilized in modern sub-micron CMOS fabrication processes on the size of the image sensor chip. Furthermore, the cost of a CMOS active pixel sensor (APS) image sensor chip substantially goes down as the pixel size goes down, whether the image sensor chip is very high resolution or not. However, there exist several optical limitations on the pixel size that make it imprudent to further reduce the pixel size beyond those limitations. A major limitation on the reduction of pixel size is that pixel sensitivity is significantly reduced as pixel size goes down. One may take refuge in using low f-number optics to allow more photons into the pixel to compensate for the reduced sensitivity of the small pixel. However, the employment of low f-number optics is associated with high cost, which may offset the low cost advantage of image sensor chips that have small pixels. Additionally, low f-number optics may introduce undesirable aberrations. Another major limitation on the reduction of pixel size is that cross-talk is considerably increased as the pixel size is decreased. Keeping cross-talk low is very critical to the proper operation of an image sensor, particularly color image sensors.","PeriodicalId":123517,"journal":{"name":"Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130014929","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: 11

Capacity occupation strategy for data messaging over non-geostationary mobile satellite communication systems 非对地静止移动卫星通信系统上数据传送的容量占用策略

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929401

Nawal A. El-fishawy, S. Khamis

引用次数: 0

Spatio-temporal channel characteristics at base station in microwave urban propagation 微波城市传播中基站的时空信道特性

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929420

H. Masui, M. Ishii, K. Sakawa, H. Shimizu, T. Kobayashi, M. Akaike

引用次数: 1

Design and development of an annotated ECG database 心电注释数据库的设计与开发

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929425

M.A. Azim, F. Abou-Chadi, H. Bakr, H. H. Soliman

{"title":"Design and development of an annotated ECG database","authors":"M.A. Azim, F. Abou-Chadi, H. Bakr, H. H. Soliman","doi":"10.1109/NRSC.2001.929425","DOIUrl":"https://doi.org/10.1109/NRSC.2001.929425","url":null,"abstract":"Annotated databases are used in the evaluation and testing of the performance of electrocardiographic (ECG) processing and data compression algorithms. They help greatly in testing and evaluating new developed systems, as they require proper validation of their performance. The present work documents the design and development of an annotated, single-channel digital ECG database. The procedures for forming the annotated database consist of five processing steps. The first step is to eliminate the different types of noise interfered with the ECG signals using digital filters. The second step is the detection of QRS-complexes. The third step is to extract quantitative parameters identifying different ECG signals. The fourth step is the classification process in which the ECG beats are classified into different categories. The last step is the annotation process: each beat is given a specific symbol. Since the formation of the database itself has significant effect on the measured performance of the system under investigation, efficient techniques that give the highest performance must be selected for each of the mentioned processing steps. The developed database is similar to the known AHA database. It consists of fifty-five records, each of period of 10 minutes and is recorded on 1.44\" floppy diskettes. The database contains five categories of ECG records: (1) ventricular arrhythmia, (2) atrial fibrillation/flutter, (3) ischaemic heart disease, (4) ECG test compression database, and (5) pacemakers. The developed database is a preliminary version for developing a complete Egyptian annotated database.","PeriodicalId":123517,"journal":{"name":"Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134085432","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

Performance of concatenated turbo-trellis coded modulation for mobile satellite channels 移动卫星信道串联涡轮栅格编码调制性能研究

Proceedings of the Eighteenth National Radio Science Conference. NRSC'2001 (IEEE Cat. No.01EX462) Pub Date : 2001-03-27 DOI: 10.1109/NRSC.2001.929394

R. El-Swady, M.A. Bahie Eldin, L. F. Gergis

引用次数: 1