Dalia mohammed Nashaat - Academia.edu (original) (raw)
Papers by Dalia mohammed Nashaat
IEEE Antennas and Propagation Society International Symposium. Digest. Held in conjunction with: USNC/CNC/URSI North American Radio Sci. Meeting (Cat. No.03CH37450)
A dual-band internal planar inverted-F antenna (PIFA) is proposed for 2.4 GHz Bluetooth (ISM) and... more A dual-band internal planar inverted-F antenna (PIFA) is proposed for 2.4 GHz Bluetooth (ISM) and wireless area network (WLAN) 5.2 GHz (IEEE 802.116) applications. The antenna has a rigid design with a foam substrate so it can be integrated easily with the Bluetooth housing of personal digital assistant (PDA) devices. A U-shaped slot is etched in the top plate to achieve the dual-band operation. The antenna has a single feed with total compact size of 14×15×6 mm3. The antenna bandwidth is 4% and 4.3% at the lower and upper frequencies, respectively.
Microwave and Optical Technology Letters, 2005
From this transfer function, we can obtain the network parameters of the filter, such as coupling... more From this transfer function, we can obtain the network parameters of the filter, such as coupling matrix (M) and input/output coupling coefficients (R in , R out) using the well-known method in [5]:
Microwave and Optical Technology Letters, 2007
A novel multi‐ and ultrawideband operation of a single feed triangular antenna are presented. For... more A novel multi‐ and ultrawideband operation of a single feed triangular antenna are presented. For multi and UWB operation, the proposed design are achieved by inserting U shaped slot on the triangular PIFA with unequal arms, choosing between multi and ultrawide band by adjusting feeding position. Five resonant band of multi band operation is obtained in S‐band, Q‐band, bluetooth band, and WLAN band with acceptable impedance bandwidth. There is an increase in the number of resonant operating frequencies by etching U slot on the shorting feed plate. Ultrawideband is achieved by adjusting coaxial feed to obtained impedance bandwidth 27%. Enhancement impedance bandwidth by using folded shorting plate to improving bandwidth to achieve ultrawide bandwidth around 53%. The proposed antennas have acceptable gain around 11.5 dB. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2039–2043, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22576
Nowadays, in modern mobile and wireless communication systems, there is an increased demand for c... more Nowadays, in modern mobile and wireless communication systems, there is an increased demand for compact, wide bandwidth and low-cost antennas with dual band capability. In this paper, two shapes for a low cost reduced size PIFA with wide bandwidth are investigated. The antenna substrate is from a cheap foam material with r ε =1.07. The antenna is fed by single coaxial feed. Size reduction is achieved by cutting U-shaped slot on the radiating surface of the PIFA structure. The antenna size becomes (0.22 λ x 0.18 λ). Wide bandwidth is reached by making the U-shaped slot with two unequal arms. Moreover, dual operating frequencies are achieved by cutting either L-shaped or U-shaped slits on the coupled feeding part of the radiating surface. The antenna resonates in Bluetooth ISM band at 2.4 GHz as well as in WLAN band at 5.2GHz. The bandwidths are about 31% and 7.5% for the lower and upper bands, respectively. The proposed antenna is simple in structure compared to regular stacked or coplanar parasitic patch antennas that, makes it suitable for most mobile communication applications.
MILCOM 2007 - IEEE Military Communications Conference, 2007
In this paper, the effect of shorting wall length on the circular polarization of shorted microst... more In this paper, the effect of shorting wall length on the circular polarization of shorted microstrip patch antenna is examined. The theoretical analysis is based on the High Frequency Software Simulator (HFSS ®). A designed antenna for the GPS application at the civilian GPS frequency (1.575 GHz) has been fabricated and measured. The measured data for the fabricated antenna is taken by 8719 ES vector network analyzer. Results of the designed antenna show good circularly polarized with a reduction in its size by 24.6 % from the conventional rectangular microstrip patch antenna. Simulated and measured results for the proposed antenna are presented.
IEEE Transactions on Antennas and Propagation, 2011
AbstractFour types of EBG structures are proposed and used in the design of a patch antenna arra... more AbstractFour types of EBG structures are proposed and used in the design of a patch antenna array to improve the bandwidth, gain and reduce the overall array size. The four ground plane designs for the 2 2 microstrip patch antenna array (MPAA) are; spiral artificial magnetic ...
2009 IEEE Antennas and Propagation Society International Symposium, 2009
Abstract: - As wireless communications applications continue to require more and more bandwidth, ... more Abstract: - As wireless communications applications continue to require more and more bandwidth, there has been continued increase in demand for ultra-wide bandwidth antennas. Planar monopole antennas are generally suitable for mobile applications and ...
2009 IEEE Antennas and Propagation Society International Symposium, 2009
Abstract:- Microstrip patch antennas with inset feed have been studied extensively over the past ... more Abstract:- Microstrip patch antennas with inset feed have been studied extensively over the past two decades because of its practical advantage when used in mobile wireless systems. The length of MPA, however, is comparable to a half wavelength with single resonant ...
2009 IEEE Antennas and Propagation Society International Symposium, 2009
Abstract:- This paper presents an investigation of both electromagnetic wave model and equivalent... more Abstract:- This paper presents an investigation of both electromagnetic wave model and equivalent circuit model for microstrip patch antenna (MPA) with rectangular defected ground plane structure (RDGS). The objective of the proposed design is to reduce antenna size from Wi-Fi ...
Proceedings of the Twenty Third National Radio Science Conference (NRSC'2006), 2006
... Miniturized E-Shaped Dual Band PIFA on FR4 Substrates Dalia Mohamed Nashaat and HIala Elsadek... more ... Miniturized E-Shaped Dual Band PIFA on FR4 Substrates Dalia Mohamed Nashaat and HIala Elsadek Microstrip Department, Electronics Research Institute, National Reasearch Center Buildings, Eltahrir St., Dokki, Giza, Egypt, 12622 dalial79175(?vahoo.com Abstract ...
Microwave and Optical Technology Letters, 2004
The definitive element of any wireless device is its antenna. In this paper, a multiband planar i... more The definitive element of any wireless device is its antenna. In this paper, a multiband planar inverted-F antenna (PIFA) is miniaturized. The results show that a 68%-82% size reduction can be achieved. Two techniques for reduction are utilized: (i) adding lumped load and (ii) miniaturizing the geometry by using the fractal concept. New PIFA configurations are reached. Quad-band operation is achieved.
Microwave and Optical Technology Letters, 2005
From this transfer function, we can obtain the network parameters of the filter, such as coupling... more From this transfer function, we can obtain the network parameters of the filter, such as coupling matrix (M) and input/output coupling coefficients (R in , R out) using the well-known method in [5]:
Journal of Electromagnetic Waves and Applications, 2007
ABSTRACT
IEEE Transactions on Antennas and Propagation, 2005
In this paper, a novel compact single feed quad-band planar inverted F-antenna (PIFA) is presente... more In this paper, a novel compact single feed quad-band planar inverted F-antenna (PIFA) is presented. Two techniques to reduce the physical size are illustrated. First, we insert U-shaped slits within the antenna-radiating surface. This forces the current to flow around the obstacles hence, reducing the resonant frequency. This technique reduces the size by about 30% from the original PIFA. Second,
The Applied Computational Electromagnetics Society Journal (ACES), 2021
In this paper, a switched beam antenna system consists of four Vivaldi antennas for vehicle-to-ve... more In this paper, a switched beam antenna system consists of four Vivaldi antennas for vehicle-to-vehicle communication is presented. The proposed design is realized on a substrate material of “Rogers 5880” with εr=2.2,tanδ=0.002,andεr=2.2,tanδ=0.002,and0.508-mm substrate thickness. The antenna is designed to operate at a center frequency of 28 GHz with operating bandwidth of 1.463 GHz. An overall realized gain of 9.78 dBi is achieved at the intended center frequency. The proposed antenna is designed and simulated using CSTMWS. It is also fabricated using photolithography techniques and measured using R&S vector network analyzer. Good agreement is obtained between both CSTMWS and measured results.
Journal of Sensors, 2020
IoT system becomes a hot topic nowadays for smart home. IoT helps devices to communicate together... more IoT system becomes a hot topic nowadays for smart home. IoT helps devices to communicate together without human intervention inside home, so it is offering many challenges. A new smart home IoT platform powered using electromagnetic energy harvesting is proposed in this paper. It contains a high gain transmitted antenna array and efficient circularly polarized array rectenna system to harvest enough power from any direction to increase lifetime of the batteries used in the IoT system. Optimized energy consumption, the software with adopting the Zigbee protocol of the sensor node, and a low-power microcontroller are used to operate in lower power modes. The proposed system has an 84.6-day lifetime which is approximately 10 times the lifetime for a similar system. On the other hand, the proposed power management circuit is operated at 0.3 V DC to boost the voltage to ~3.7 V from radio frequency energy harvesting and manage battery level to increase the battery lifetime. A predictive i...
Sensors, 2021
This paper presents a rapid diagnostic device for the detection of the pandemic coronavirus (COVI... more This paper presents a rapid diagnostic device for the detection of the pandemic coronavirus (COVID-19) using a micro-immunosensor cavity resonator. Coronavirus has been declared an international public health crisis, so it is important to design quick diagnostic methods for the detection of infected cases, especially in rural areas, to limit the spread of the virus. Herein, a proof-of-concept is presented for a portable laboratory device for the detection of the SARS-CoV-2 virus using electromagnetic biosensors. This device is a microwave cavity resonator (MCR) composed of a sensor operating at industrial, scientific and medical (ISM) 2.45 GHz inserted in 3D housing. The changes of electrical properties of measured serum samples after passing the sensor surface are presented. The three change parameters of the sensor are resonating frequency value, amplitude and phase of the reflection coefficient |S11|. This immune-sensor offers a portable, rapid and accurate diagnostic method for ...
Journal of Electrical Engineering, 2021
In this paper, a miniaturized implantable antenna system for biomedical applications is presented... more In this paper, a miniaturized implantable antenna system for biomedical applications is presented. The system consists of almost two similar patch antennas, named internal and external. The internal antenna is implanted inside the body at a depth of 2 mm, and the external antenna is to be attached to the body aligned with the internal one. The antenna system consists of implant-side antenna with dimensions are 10.25×10.25×1.27 mm3 , while the external antenna dimensions are 11.1×11.1×1.27 mm3. The proposed antennas designs showed dual resonant frequency on ISM bands (ie , 915 MHz and 2450 MHz ). The computed -10 dB bandwidth considering three-layer human phantom demonstrates that a bandwidth of 870 to 970 MHz and 2.38 to 2.47 GHz for internal and external antennas are achieved. The Specific Absorption Rate (SAR) has been considered for health care consideration. The measured and simulated scattering parameters are compared, and good agreements are achieved. The proposed antenna syst...
Wireless Energy Transfer Technology [Working Title], 2019
With the rapid development of the wireless systems and demands of low-power integrated electronic... more With the rapid development of the wireless systems and demands of low-power integrated electronic circuits, various research trends have tended to study the feasibility of powering these circuits by harvesting free energy from ambient electromagnetic space or by using dedicated RF source. Wireless power transmission (WPT) technology was first pursued by Tesla over a century ago. However, it faced several challenges for deployment in real applications. Recently, energy harvesting and WPT technologies have received much attention as a clean and renewable power source. Rectenna (rectifying antenna) system can be used for remotely charging batteries in several sensor networks at internet of things (IoT) applications as commonly used in smart buildings, implanted medical devices and automotive applications. Rectenna, which is used to convert from RF energy to usable DC electrical energy, is mainly a combination between a receiving antenna and a rectifier circuit. This chapter will present several designs for single and multiband rectennas with different characteristics for energy harvesting applications. Single and multiband antennas as well as rectifier circuits with matching networks are introduced for complete successful rectenna circuit models. At the end of the chapter, a dual-band rectenna example is introduced with a detailed description for each section of the rectenna.
IEEE Antennas and Propagation Society International Symposium. Digest. Held in conjunction with: USNC/CNC/URSI North American Radio Sci. Meeting (Cat. No.03CH37450)
A dual-band internal planar inverted-F antenna (PIFA) is proposed for 2.4 GHz Bluetooth (ISM) and... more A dual-band internal planar inverted-F antenna (PIFA) is proposed for 2.4 GHz Bluetooth (ISM) and wireless area network (WLAN) 5.2 GHz (IEEE 802.116) applications. The antenna has a rigid design with a foam substrate so it can be integrated easily with the Bluetooth housing of personal digital assistant (PDA) devices. A U-shaped slot is etched in the top plate to achieve the dual-band operation. The antenna has a single feed with total compact size of 14×15×6 mm3. The antenna bandwidth is 4% and 4.3% at the lower and upper frequencies, respectively.
Microwave and Optical Technology Letters, 2005
From this transfer function, we can obtain the network parameters of the filter, such as coupling... more From this transfer function, we can obtain the network parameters of the filter, such as coupling matrix (M) and input/output coupling coefficients (R in , R out) using the well-known method in [5]:
Microwave and Optical Technology Letters, 2007
A novel multi‐ and ultrawideband operation of a single feed triangular antenna are presented. For... more A novel multi‐ and ultrawideband operation of a single feed triangular antenna are presented. For multi and UWB operation, the proposed design are achieved by inserting U shaped slot on the triangular PIFA with unequal arms, choosing between multi and ultrawide band by adjusting feeding position. Five resonant band of multi band operation is obtained in S‐band, Q‐band, bluetooth band, and WLAN band with acceptable impedance bandwidth. There is an increase in the number of resonant operating frequencies by etching U slot on the shorting feed plate. Ultrawideband is achieved by adjusting coaxial feed to obtained impedance bandwidth 27%. Enhancement impedance bandwidth by using folded shorting plate to improving bandwidth to achieve ultrawide bandwidth around 53%. The proposed antennas have acceptable gain around 11.5 dB. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2039–2043, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22576
Nowadays, in modern mobile and wireless communication systems, there is an increased demand for c... more Nowadays, in modern mobile and wireless communication systems, there is an increased demand for compact, wide bandwidth and low-cost antennas with dual band capability. In this paper, two shapes for a low cost reduced size PIFA with wide bandwidth are investigated. The antenna substrate is from a cheap foam material with r ε =1.07. The antenna is fed by single coaxial feed. Size reduction is achieved by cutting U-shaped slot on the radiating surface of the PIFA structure. The antenna size becomes (0.22 λ x 0.18 λ). Wide bandwidth is reached by making the U-shaped slot with two unequal arms. Moreover, dual operating frequencies are achieved by cutting either L-shaped or U-shaped slits on the coupled feeding part of the radiating surface. The antenna resonates in Bluetooth ISM band at 2.4 GHz as well as in WLAN band at 5.2GHz. The bandwidths are about 31% and 7.5% for the lower and upper bands, respectively. The proposed antenna is simple in structure compared to regular stacked or coplanar parasitic patch antennas that, makes it suitable for most mobile communication applications.
MILCOM 2007 - IEEE Military Communications Conference, 2007
In this paper, the effect of shorting wall length on the circular polarization of shorted microst... more In this paper, the effect of shorting wall length on the circular polarization of shorted microstrip patch antenna is examined. The theoretical analysis is based on the High Frequency Software Simulator (HFSS ®). A designed antenna for the GPS application at the civilian GPS frequency (1.575 GHz) has been fabricated and measured. The measured data for the fabricated antenna is taken by 8719 ES vector network analyzer. Results of the designed antenna show good circularly polarized with a reduction in its size by 24.6 % from the conventional rectangular microstrip patch antenna. Simulated and measured results for the proposed antenna are presented.
IEEE Transactions on Antennas and Propagation, 2011
AbstractFour types of EBG structures are proposed and used in the design of a patch antenna arra... more AbstractFour types of EBG structures are proposed and used in the design of a patch antenna array to improve the bandwidth, gain and reduce the overall array size. The four ground plane designs for the 2 2 microstrip patch antenna array (MPAA) are; spiral artificial magnetic ...
2009 IEEE Antennas and Propagation Society International Symposium, 2009
Abstract: - As wireless communications applications continue to require more and more bandwidth, ... more Abstract: - As wireless communications applications continue to require more and more bandwidth, there has been continued increase in demand for ultra-wide bandwidth antennas. Planar monopole antennas are generally suitable for mobile applications and ...
2009 IEEE Antennas and Propagation Society International Symposium, 2009
Abstract:- Microstrip patch antennas with inset feed have been studied extensively over the past ... more Abstract:- Microstrip patch antennas with inset feed have been studied extensively over the past two decades because of its practical advantage when used in mobile wireless systems. The length of MPA, however, is comparable to a half wavelength with single resonant ...
2009 IEEE Antennas and Propagation Society International Symposium, 2009
Abstract:- This paper presents an investigation of both electromagnetic wave model and equivalent... more Abstract:- This paper presents an investigation of both electromagnetic wave model and equivalent circuit model for microstrip patch antenna (MPA) with rectangular defected ground plane structure (RDGS). The objective of the proposed design is to reduce antenna size from Wi-Fi ...
Proceedings of the Twenty Third National Radio Science Conference (NRSC'2006), 2006
... Miniturized E-Shaped Dual Band PIFA on FR4 Substrates Dalia Mohamed Nashaat and HIala Elsadek... more ... Miniturized E-Shaped Dual Band PIFA on FR4 Substrates Dalia Mohamed Nashaat and HIala Elsadek Microstrip Department, Electronics Research Institute, National Reasearch Center Buildings, Eltahrir St., Dokki, Giza, Egypt, 12622 dalial79175(?vahoo.com Abstract ...
Microwave and Optical Technology Letters, 2004
The definitive element of any wireless device is its antenna. In this paper, a multiband planar i... more The definitive element of any wireless device is its antenna. In this paper, a multiband planar inverted-F antenna (PIFA) is miniaturized. The results show that a 68%-82% size reduction can be achieved. Two techniques for reduction are utilized: (i) adding lumped load and (ii) miniaturizing the geometry by using the fractal concept. New PIFA configurations are reached. Quad-band operation is achieved.
Microwave and Optical Technology Letters, 2005
From this transfer function, we can obtain the network parameters of the filter, such as coupling... more From this transfer function, we can obtain the network parameters of the filter, such as coupling matrix (M) and input/output coupling coefficients (R in , R out) using the well-known method in [5]:
Journal of Electromagnetic Waves and Applications, 2007
ABSTRACT
IEEE Transactions on Antennas and Propagation, 2005
In this paper, a novel compact single feed quad-band planar inverted F-antenna (PIFA) is presente... more In this paper, a novel compact single feed quad-band planar inverted F-antenna (PIFA) is presented. Two techniques to reduce the physical size are illustrated. First, we insert U-shaped slits within the antenna-radiating surface. This forces the current to flow around the obstacles hence, reducing the resonant frequency. This technique reduces the size by about 30% from the original PIFA. Second,
The Applied Computational Electromagnetics Society Journal (ACES), 2021
In this paper, a switched beam antenna system consists of four Vivaldi antennas for vehicle-to-ve... more In this paper, a switched beam antenna system consists of four Vivaldi antennas for vehicle-to-vehicle communication is presented. The proposed design is realized on a substrate material of “Rogers 5880” with εr=2.2,tanδ=0.002,andεr=2.2,tanδ=0.002,and0.508-mm substrate thickness. The antenna is designed to operate at a center frequency of 28 GHz with operating bandwidth of 1.463 GHz. An overall realized gain of 9.78 dBi is achieved at the intended center frequency. The proposed antenna is designed and simulated using CSTMWS. It is also fabricated using photolithography techniques and measured using R&S vector network analyzer. Good agreement is obtained between both CSTMWS and measured results.
Journal of Sensors, 2020
IoT system becomes a hot topic nowadays for smart home. IoT helps devices to communicate together... more IoT system becomes a hot topic nowadays for smart home. IoT helps devices to communicate together without human intervention inside home, so it is offering many challenges. A new smart home IoT platform powered using electromagnetic energy harvesting is proposed in this paper. It contains a high gain transmitted antenna array and efficient circularly polarized array rectenna system to harvest enough power from any direction to increase lifetime of the batteries used in the IoT system. Optimized energy consumption, the software with adopting the Zigbee protocol of the sensor node, and a low-power microcontroller are used to operate in lower power modes. The proposed system has an 84.6-day lifetime which is approximately 10 times the lifetime for a similar system. On the other hand, the proposed power management circuit is operated at 0.3 V DC to boost the voltage to ~3.7 V from radio frequency energy harvesting and manage battery level to increase the battery lifetime. A predictive i...
Sensors, 2021
This paper presents a rapid diagnostic device for the detection of the pandemic coronavirus (COVI... more This paper presents a rapid diagnostic device for the detection of the pandemic coronavirus (COVID-19) using a micro-immunosensor cavity resonator. Coronavirus has been declared an international public health crisis, so it is important to design quick diagnostic methods for the detection of infected cases, especially in rural areas, to limit the spread of the virus. Herein, a proof-of-concept is presented for a portable laboratory device for the detection of the SARS-CoV-2 virus using electromagnetic biosensors. This device is a microwave cavity resonator (MCR) composed of a sensor operating at industrial, scientific and medical (ISM) 2.45 GHz inserted in 3D housing. The changes of electrical properties of measured serum samples after passing the sensor surface are presented. The three change parameters of the sensor are resonating frequency value, amplitude and phase of the reflection coefficient |S11|. This immune-sensor offers a portable, rapid and accurate diagnostic method for ...
Journal of Electrical Engineering, 2021
In this paper, a miniaturized implantable antenna system for biomedical applications is presented... more In this paper, a miniaturized implantable antenna system for biomedical applications is presented. The system consists of almost two similar patch antennas, named internal and external. The internal antenna is implanted inside the body at a depth of 2 mm, and the external antenna is to be attached to the body aligned with the internal one. The antenna system consists of implant-side antenna with dimensions are 10.25×10.25×1.27 mm3 , while the external antenna dimensions are 11.1×11.1×1.27 mm3. The proposed antennas designs showed dual resonant frequency on ISM bands (ie , 915 MHz and 2450 MHz ). The computed -10 dB bandwidth considering three-layer human phantom demonstrates that a bandwidth of 870 to 970 MHz and 2.38 to 2.47 GHz for internal and external antennas are achieved. The Specific Absorption Rate (SAR) has been considered for health care consideration. The measured and simulated scattering parameters are compared, and good agreements are achieved. The proposed antenna syst...
Wireless Energy Transfer Technology [Working Title], 2019
With the rapid development of the wireless systems and demands of low-power integrated electronic... more With the rapid development of the wireless systems and demands of low-power integrated electronic circuits, various research trends have tended to study the feasibility of powering these circuits by harvesting free energy from ambient electromagnetic space or by using dedicated RF source. Wireless power transmission (WPT) technology was first pursued by Tesla over a century ago. However, it faced several challenges for deployment in real applications. Recently, energy harvesting and WPT technologies have received much attention as a clean and renewable power source. Rectenna (rectifying antenna) system can be used for remotely charging batteries in several sensor networks at internet of things (IoT) applications as commonly used in smart buildings, implanted medical devices and automotive applications. Rectenna, which is used to convert from RF energy to usable DC electrical energy, is mainly a combination between a receiving antenna and a rectifier circuit. This chapter will present several designs for single and multiband rectennas with different characteristics for energy harvesting applications. Single and multiband antennas as well as rectifier circuits with matching networks are introduced for complete successful rectenna circuit models. At the end of the chapter, a dual-band rectenna example is introduced with a detailed description for each section of the rectenna.