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Author

Hilal A. Fadhil

Other affiliations: Al-Farabi University
Bio: Hilal A. Fadhil is an academic researcher from Universiti Malaysia Perlis. The author has contributed to research in topics: Code division multiple access & Constant-weight code. The author has an hindex of 18, co-authored 132 publications receiving 1196 citations. Previous affiliations of Hilal A. Fadhil include Al-Farabi University.


Papers
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Journal ArticleDOI
01 Oct 2013-Optik
TL;DR: From the result analysis, FSO wavelength with 1550 nm produces less effect in atmospheric attenuation, and it is recommended to develop a system of quality-free space optics for a high data rate transmission.

168 citations

Journal ArticleDOI
TL;DR: Simulation results show this new Multi-Diagonal code for Spectral Amplitude – Coding Optical Code Division Multiple Access to provide a much better performance compared to Modified Quadratic Congruence (MQC) code and Random Diagonal (RD) code.

100 citations

Journal ArticleDOI
TL;DR: It is shown that the proposed new spectral direct detection technique utilizing RD code considerably improves the performance compared with the conventional SAC complementary subtraction technique.

91 citations

Journal ArticleDOI
TL;DR: Results show that by choosing code weight of 4 and optimizing number of users per sequence, the MS code supports up to 82 users, each operating at a bit-rate of 622 Mbps with reference to the Bit Error Rate (BER) of 10−9.
Abstract: A Multi-Service Optical Code Division Multiple Access (MS-OCDMA) code based on Spectral Amplitude Coding (SAC) is proposed in this paper. The advantage of proposed code on setting a variable number of users in a basic code matrix with a fixed code weight makes it more flexible in generating codewords. The appropriate quality of service required for various network applications can be provided by choosing a different number of users for the basic code matrix of MS code. The properties of the proposed code is compared with other OCDMA codes in terms of code length and maximum cross-correlation. The performance of the MS code mathematically analysed and probability of error for users is plotted as a function of the number of active users and optical received power. Shot, phase induced intensity and thermal noises are considered in mathematical analysis. Results show that by choosing code weight of 4 and optimizing number of users per sequence, the MS code supports up to 82 users, each operating at a bit-rate of 622 Mbps with reference to the Bit Error Rate (BER) of 10−9.

54 citations

Journal ArticleDOI
TL;DR: The analytical and the simulation results reveal that the proposed 2D-MD code outperforms the other codes and a large number of simultaneous users can be accommodated at low BER and high data rate.

46 citations


Cited by
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Journal ArticleDOI

[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal Article
J. Walkup1
TL;DR: Development of this more comprehensive model of the behavior of light draws upon the use of tools traditionally available to the electrical engineer, such as linear system theory and the theory of stochastic processes.
Abstract: Course Description This is an advanced course in which we explore the field of Statistical Optics. Topics covered include such subjects as the statistical properties of natural (thermal) and laser light, spatial and temporal coherence, effects of partial coherence on optical imaging instruments, effects on imaging due to randomly inhomogeneous media, and a statistical treatment of the detection of light. Development of this more comprehensive model of the behavior of light draws upon the use of tools traditionally available to the electrical engineer, such as linear system theory and the theory of stochastic processes.

1,364 citations

01 Dec 1976
TL;DR: A simple method of estimating the average daily radiation for each calendar month on surfaces facing directly towards the equator has been presented by Liu and Jordan as discussed by the authors, verified with experimental measurements and extended to allow calculation of monthly average radiation on surfaces of a wide range of orientations.
Abstract: Several simplified design procedures for solar energy systems require monthly average meteorological data. Monthly average daily totals of the solar radiation incident on a horizontal surface are available. However, radiation data on tilted surfaces, required by the design procedures, are generally not available. A simple method of estimating the average daily radiation for each calendar month on surfaces facing directly towards the equator has been presented by Liu and Jordan [1]. This method is verified with experimental measurements and extended to allow calculation of monthly average radiation on surfaces of a wide range of orientations.

650 citations

ReportDOI
08 Dec 1998
TL;DR: In this article, the authors consider the unique features of UWB technology and propose that the FCC should consider them in considering changes to Part 15 and take into account their unique features for radar and communications uses.
Abstract: In general, Micropower Impulse Radar (MIR) depends on Ultra-Wideband (UWB) transmission systems. UWB technology can supply innovative new systems and products that have an obvious value for radar and communications uses. Important applications include bridge-deck inspection systems, ground penetrating radar, mine detection, and precise distance resolution for such things as liquid level measurement. Most of these UWB inspection and measurement methods have some unique qualities, which need to be pursued. Therefore, in considering changes to Part 15 the FCC needs to take into account the unique features of UWB technology. MIR is applicable to two general types of UWB systems: radar systems and communications systems. Currently LLNL and its licensees are focusing on radar or radar type systems. LLNL is evaluating MIR for specialized communication systems. MIR is a relatively low power technology. Therefore, MIR systems seem to have a low potential for causing harmful interference to other users of the spectrum since the transmitted signal is spread over a wide bandwidth, which results in a relatively low spectral power density.

644 citations