This paper proposes a new compact size and efficient microstrip patch antenna using the concept o... more This paper proposes a new compact size and efficient microstrip patch antenna using the concept of high impedance wire (HIW). The parameters of the HIW unit cell have been analyzed, the theory and design flow of the antenna have been developed, and the performance of the proposed antenna has been studied with EM simulations and confirmed with measurements.
Nonimaging Optics: Efficient Design for Illumination and Solar Concentration XI, 2014
ABSTRACT Cities and towns around the world are becoming more condensed due to the shrinking amoun... more ABSTRACT Cities and towns around the world are becoming more condensed due to the shrinking amount of buildable areas, which significantly reduces the amount of light that occupants have access to. This lack of natural lighting results in health, safety and quality of life degradation. This paper presents a new technique of transmitting sunlight downward into narrow alleys and streets, by using a daylighting guiding acrylic panel that is capable of changing the direction and distribution of the incident light. The core of the proposed daylight guidance system is made up of light transmission panels with high quality. The corrugations have sine wave shaped cross-section so that the panel functions as an optical diffuser perpendicular to the direction of sunlight propagation. The day lighting system consists of the corrugated panels and a lattice frame, which supports the panel. The proposed system is to be mounted on the building roof facing the sun so as to redirect the incident sunlight downward into the narrow alleys or streets. Since building sizes and orientations are different the frame is arranged such that substantially deep light penetration and high luminance level can be achieved. Simulation results show that the proposed panel improves the illuminance values by more than 200% and 400% in autumn and winter, respectively, provides fan-out angle that exceeds 80° for certain solar altitudes and the transmitted power percentage varies from 40% to 90% as the solar altitude varies from 10° to 80°. Experimental results are in a good agreement with the simulations.
IEEE Transactions on Microwave Theory and Techniques, 2000
Page 1. 1584 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 6, JUNE 2010 On t... more Page 1. 1584 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 6, JUNE 2010 On the Applications of the Coupled-Line Composite Right/Left-Handed Unit Cell Ahmed E. Fouda, Student Member ...
IEEE Antennas and Wireless Propagation Letters, 2000
... AbstractThis letter introduces the concept of high-impedance wire (HIW), proposes an impleme... more ... AbstractThis letter introduces the concept of high-impedance wire (HIW), proposes an implementation for it, and provides new insight to conventional slotted planar transmission lines. ... An HIW is one single wire that can have high reac-tive impedance per unit length. ...
Page 1. WElA-1 NOVEL DESIGN FOR COPLANAR WAVEGUIDE TO MICROSTRIP TRANSITION* A m ME Sakat**"... more Page 1. WElA-1 NOVEL DESIGN FOR COPLANAR WAVEGUIDE TO MICROSTRIP TRANSITION* A m ME Sakat**"), student member, IEEE, Kawthar A. Zaki* Fellow, IEEE, William Johnson** member IEEE, and Chi H. Lee*, Fellow, IEEE ...
With the high population growth rate, especially in developing countries, and the scarcity of lan... more With the high population growth rate, especially in developing countries, and the scarcity of land resources, buildings are becoming so close to each other, depriving the lower floors and the alleys from sunlight and consequently causing health problems. Therefore, there is an urgent need for cost-effective efficient light redirecting panels that guide sun rays into those dim places. In this paper, we address this problem. A novel sine wave based panel is presented to redirect/diverge light downward and enhance the illumination level in those dark places. Simulation results show that the proposed panel improves the illuminance values by more than 200% and 400% in autumn and winter respectively, operates over wide solar altitude ranges, and redirects light efficiently. Experimental and simulation results are in good agreement.
Journal of Electromagnetic Waves and Applications, 2001
Conductor backed coplanar waveguide (CPWG) with etching between the metal strips on the surface h... more Conductor backed coplanar waveguide (CPWG) with etching between the metal strips on the surface has been studied using the mode matching technique. The characteristics of the CPWG was first studied and compared to commercial software. The analysis shows that etching few microns from the substrate increases the characteristic impedance by more than 30% for CPWG with small width and small
Proceedings of the Twenty-First National Radio Science Conference, 2004. NRSC 2004., 2004
A simple methodology is developed to determine the value of MEMS shunt switch on-state capacitanc... more A simple methodology is developed to determine the value of MEMS shunt switch on-state capacitance using established design equations for planar transmission lines. Results agreed with the on-state values provided by 3D electrostatic simulator with an error of less than 4%.
Proceedings of the Twenty-First National Radio Science Conference, 2004. NRSC 2004., 2004
... I. Introduction Balanced circuits have been used for many years in different applications suc... more ... I. Introduction Balanced circuits have been used for many years in different applications such as double balanced mixers, push pull amplifiers, multipliers, and phase shiflers designs in wireless systems. ... 3, 1995. [5] Kian Sen Ang and Yoke Choy Leong; "Converting baluns into ...
International Topical Meeting on Microwave Photonics, 2002
Two metal-semiconductor-metal (MSM) photodetectors are integrated monolithically with coplanar wa... more Two metal-semiconductor-metal (MSM) photodetectors are integrated monolithically with coplanar waveguide transmission line. By illuminating this structure with CW light and taking the difference between the two detectors, 9-10 dB noise cancellation was achieved. Another demonstration of noise cancellation is then proposed. Measurements show that the noise can be reduced by 3 dB without degrading the signal to noise ratio.
This paper proposes a new compact size and efficient microstrip patch antenna using the concept o... more This paper proposes a new compact size and efficient microstrip patch antenna using the concept of high impedance wire (HIW). The parameters of the HIW unit cell have been analyzed, the theory and design flow of the antenna have been developed, and the performance of the proposed antenna has been studied with EM simulations and confirmed with measurements.
Nonimaging Optics: Efficient Design for Illumination and Solar Concentration XI, 2014
ABSTRACT Cities and towns around the world are becoming more condensed due to the shrinking amoun... more ABSTRACT Cities and towns around the world are becoming more condensed due to the shrinking amount of buildable areas, which significantly reduces the amount of light that occupants have access to. This lack of natural lighting results in health, safety and quality of life degradation. This paper presents a new technique of transmitting sunlight downward into narrow alleys and streets, by using a daylighting guiding acrylic panel that is capable of changing the direction and distribution of the incident light. The core of the proposed daylight guidance system is made up of light transmission panels with high quality. The corrugations have sine wave shaped cross-section so that the panel functions as an optical diffuser perpendicular to the direction of sunlight propagation. The day lighting system consists of the corrugated panels and a lattice frame, which supports the panel. The proposed system is to be mounted on the building roof facing the sun so as to redirect the incident sunlight downward into the narrow alleys or streets. Since building sizes and orientations are different the frame is arranged such that substantially deep light penetration and high luminance level can be achieved. Simulation results show that the proposed panel improves the illuminance values by more than 200% and 400% in autumn and winter, respectively, provides fan-out angle that exceeds 80° for certain solar altitudes and the transmitted power percentage varies from 40% to 90% as the solar altitude varies from 10° to 80°. Experimental results are in a good agreement with the simulations.
IEEE Transactions on Microwave Theory and Techniques, 2000
Page 1. 1584 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 6, JUNE 2010 On t... more Page 1. 1584 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 58, NO. 6, JUNE 2010 On the Applications of the Coupled-Line Composite Right/Left-Handed Unit Cell Ahmed E. Fouda, Student Member ...
IEEE Antennas and Wireless Propagation Letters, 2000
... AbstractThis letter introduces the concept of high-impedance wire (HIW), proposes an impleme... more ... AbstractThis letter introduces the concept of high-impedance wire (HIW), proposes an implementation for it, and provides new insight to conventional slotted planar transmission lines. ... An HIW is one single wire that can have high reac-tive impedance per unit length. ...
Page 1. WElA-1 NOVEL DESIGN FOR COPLANAR WAVEGUIDE TO MICROSTRIP TRANSITION* A m ME Sakat**"... more Page 1. WElA-1 NOVEL DESIGN FOR COPLANAR WAVEGUIDE TO MICROSTRIP TRANSITION* A m ME Sakat**"), student member, IEEE, Kawthar A. Zaki* Fellow, IEEE, William Johnson** member IEEE, and Chi H. Lee*, Fellow, IEEE ...
With the high population growth rate, especially in developing countries, and the scarcity of lan... more With the high population growth rate, especially in developing countries, and the scarcity of land resources, buildings are becoming so close to each other, depriving the lower floors and the alleys from sunlight and consequently causing health problems. Therefore, there is an urgent need for cost-effective efficient light redirecting panels that guide sun rays into those dim places. In this paper, we address this problem. A novel sine wave based panel is presented to redirect/diverge light downward and enhance the illumination level in those dark places. Simulation results show that the proposed panel improves the illuminance values by more than 200% and 400% in autumn and winter respectively, operates over wide solar altitude ranges, and redirects light efficiently. Experimental and simulation results are in good agreement.
Journal of Electromagnetic Waves and Applications, 2001
Conductor backed coplanar waveguide (CPWG) with etching between the metal strips on the surface h... more Conductor backed coplanar waveguide (CPWG) with etching between the metal strips on the surface has been studied using the mode matching technique. The characteristics of the CPWG was first studied and compared to commercial software. The analysis shows that etching few microns from the substrate increases the characteristic impedance by more than 30% for CPWG with small width and small
Proceedings of the Twenty-First National Radio Science Conference, 2004. NRSC 2004., 2004
A simple methodology is developed to determine the value of MEMS shunt switch on-state capacitanc... more A simple methodology is developed to determine the value of MEMS shunt switch on-state capacitance using established design equations for planar transmission lines. Results agreed with the on-state values provided by 3D electrostatic simulator with an error of less than 4%.
Proceedings of the Twenty-First National Radio Science Conference, 2004. NRSC 2004., 2004
... I. Introduction Balanced circuits have been used for many years in different applications suc... more ... I. Introduction Balanced circuits have been used for many years in different applications such as double balanced mixers, push pull amplifiers, multipliers, and phase shiflers designs in wireless systems. ... 3, 1995. [5] Kian Sen Ang and Yoke Choy Leong; "Converting baluns into ...
International Topical Meeting on Microwave Photonics, 2002
Two metal-semiconductor-metal (MSM) photodetectors are integrated monolithically with coplanar wa... more Two metal-semiconductor-metal (MSM) photodetectors are integrated monolithically with coplanar waveguide transmission line. By illuminating this structure with CW light and taking the difference between the two detectors, 9-10 dB noise cancellation was achieved. Another demonstration of noise cancellation is then proposed. Measurements show that the noise can be reduced by 3 dB without degrading the signal to noise ratio.
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Papers by Amr Safwat