Microstrip Radiators: Various Microstrip Antenna Configurations. Feeding Techniques and Modeling.... more Microstrip Radiators: Various Microstrip Antenna Configurations. Feeding Techniques and Modeling. Applications. Radiation Field. Surface Waves and Photonic Band-Gap Structures. Analytical Models for Microstrip Antennas: Transmission Line Model. Cavity Model. Generalized Cavity Model. Multi-port Network Model (MNM). Radiation Fields. Aperture Admittance. Mutual Admittance. Model for Coaxial Probe in Microstrip Antennas. Comparison of Analytical Models. Full-Wave Analysis of Microstrip Antennas: Spectral Domain Full-Wave Analysis. Mixed-Potential Integral Equation Analysis. Finite-Difference Time Domain Analysis.Rectangular Microstrip Antenna: Models for Rectangular Patch Antenna. Design Considerations for Rectangular Patch Antennas. Tolerance Analysis of Rectangular Microstrip Antennas. Mechanical Tuning of Patch Antennas. Quarter-wave Rectangular Patch Antenna. Circular Disk and Ring Antennas: Analysis of a Circular Disk Microstrip Antenna. Design Considerations for Circular Disk An...
IEEE Transactions on Antennas and Propagation, 1986
... Mohamed Abdelrazik was born in Cairo, Egypt, on October 1, 1956. He received the BSEE, MSEE, ... more ... Mohamed Abdelrazik was born in Cairo, Egypt, on October 1, 1956. He received the BSEE, MSEE, and Ph.D. degrees from the University of Kansas, Lawrence. in 1978, 1981, and 1984 respectively. He is currently working for E-Systems Corpora-tion. ...
IEEE Transactions on Antennas and Propagation, 1986
Absrrccr-A general approach is presented for the determination of power radiated via the space wa... more Absrrccr-A general approach is presented for the determination of power radiated via the space wave and surface wave from the aperture of an arbitrarily shaped microstrip antenna. The magnetic current model is used for this, and the analysis is carried out in the Fourier domain to ...
This three part serial discusses basic design considerations for microwave integrated circuits us... more This three part serial discusses basic design considerations for microwave integrated circuits using distributed circuit approach. Various circuit elements include transmission line sections, coupled line section, resonators, junctions, bends, transitions etc. Design data for these elements is included. Of these elements, Part 1 presents available transmission line sections and coupled line sections. Part 2 includes resonators, various discontinuities and transitions.The design method of microwave integrated circuit is illustrated by considering three examples: a pin diode phase shifter, a Gunn oscillator and a hybrid branchline directional coupler. The role of discontinuity and junction reactances in the exact design of these circuits is emphasized. This portion constitutes last part of the serial.
It is shown that a line-length less than quarter wave may be used to match certain complex impeda... more It is shown that a line-length less than quarter wave may be used to match certain complex impedances to a real value. Bowman's results have been developed to achieve this and to plot the forbidden range of impedances on a Smith Chart.
This paper reviews various design formulae for a microstripline. It is pointed out that formulae ... more This paper reviews various design formulae for a microstripline. It is pointed out that formulae chosen for the design need not be more accurate than the limitations imposed by fabrication tolerances.
Closed-form expressions for various types of discontinuities in microstrip, viz. open ends, gaps,... more Closed-form expressions for various types of discontinuities in microstrip, viz. open ends, gaps, step in width, right-angle bend, T-junction and cross-junction, are derived by curve-fitting the available data. The reported expressions are accurate to within 5% in the range of parameter most commonly used. These results save computer time and may be useful in the computer-aided design of microwave integrated
A new type of leaky wave called a alow leaky wave is reported. The slow leaky waves have a phase ... more A new type of leaky wave called a alow leaky wave is reported. The slow leaky waves have a phase velocity less than the velocity of light but radiate in a direction away from end-fire. This type of wave ia supported by a metal-dielectric-thin conductor plate when
Closed form capacitance expressions for the even and odd mode characteristics of coupled microstr... more Closed form capacitance expressions for the even and odd mode characteristics of coupled microstrip lines are presented. These expressions are accurate to within 3% for 0.2≤W/h≤2, 0.05≤S/h≤2 and ϵrl. Extension of these results to asvmmetriu coupled microstrip lines indicate an accuracy of about 5% for ϵ = 10, W/h = 0.95, W2/h≥0.2and S/h≥0.1
IEEE Transactions on Microwave Theory and Techniques, 1978
... and Slotline Performances RAMESH GARG AbstractThe change in characteristics of atransmission... more ... and Slotline Performances RAMESH GARG AbstractThe change in characteristics of atransmission line due ... rev ed, New Delhi, India: Tata McGraw-Hill, 1974, ch 7, pp. 165-174 I J. Bahl and Ramesh Garg. Simple and accurate formulas for ...
IEEE Transactions on Antennas and Propagation, 2003
We have achieved 50 Ω input impedance for edge-fed narrow microstrip square-ring antennas by usin... more We have achieved 50 Ω input impedance for edge-fed narrow microstrip square-ring antennas by using the circumferential variation of current on the ring. The reference point for the current distribution has been fixed by loading the ring. The antenna has been modeled as a lossy transmission line to determine the variation of resonant frequency and input impedance with load. This
A new approach for reducing mutual coupling between planar inverted-F antennas (PIFAs) is propose... more A new approach for reducing mutual coupling between planar inverted-F antennas (PIFAs) is proposed. The approach consists of placing a resonator in between the PIFAs. The signal from the first antenna is scattered by the resonator and couples to the second antenna creating another path for mutual coupling, the phase and amplitude of which may be varied to suppress the existing coupling between the antennas. The simulation and experimental studies show that the proposed technique is able to reduce mutual coupling to about 225 dB from 23.5 dB when the antennas are placed as close as l/11. Reduced mutual coupling between closely spaced antennas may find applications in MIMO, multi-antenna systems and phased arrays.
DHT and two ^N-point DHTs, the JV-point DHT then being obtained by successive use of such decompo... more DHT and two ^N-point DHTs, the JV-point DHT then being obtained by successive use of such decompositions up to the last stage, which is different. The expected speed of a specially written split-radix FHT would be within a few per cent of that of a comparable radix-4 Hartley transform, 1-5 provided that the data sequence was of length N = 16, 64,..., where log 2 N is even. However, for N = 32, 128,..., the radix-4 program is inapplicable, and the standard radix-program is substantially slower than the radix-4.
Annular sector and circular sector microstrip antennas have been analyzed for input impedance and... more Annular sector and circular sector microstrip antennas have been analyzed for input impedance and radiation patterns. The analytical technique used is the generalized transmission line method which has the advantage of estimating the phase of aperture ...
DISCLAIMER OF WARRANTY The technical descriptions, procedures, and computer programs in this book... more DISCLAIMER OF WARRANTY The technical descriptions, procedures, and computer programs in this book have been developed with the greatest of care and they have been useful to the author in a broad range of applications; however, they are provided as is, without ...
Microstrip Radiators: Various Microstrip Antenna Configurations. Feeding Techniques and Modeling.... more Microstrip Radiators: Various Microstrip Antenna Configurations. Feeding Techniques and Modeling. Applications. Radiation Field. Surface Waves and Photonic Band-Gap Structures. Analytical Models for Microstrip Antennas: Transmission Line Model. Cavity Model. Generalized Cavity Model. Multi-port Network Model (MNM). Radiation Fields. Aperture Admittance. Mutual Admittance. Model for Coaxial Probe in Microstrip Antennas. Comparison of Analytical Models. Full-Wave Analysis of Microstrip Antennas: Spectral Domain Full-Wave Analysis. Mixed-Potential Integral Equation Analysis. Finite-Difference Time Domain Analysis.Rectangular Microstrip Antenna: Models for Rectangular Patch Antenna. Design Considerations for Rectangular Patch Antennas. Tolerance Analysis of Rectangular Microstrip Antennas. Mechanical Tuning of Patch Antennas. Quarter-wave Rectangular Patch Antenna. Circular Disk and Ring Antennas: Analysis of a Circular Disk Microstrip Antenna. Design Considerations for Circular Disk An...
IEEE Transactions on Antennas and Propagation, 1986
... Mohamed Abdelrazik was born in Cairo, Egypt, on October 1, 1956. He received the BSEE, MSEE, ... more ... Mohamed Abdelrazik was born in Cairo, Egypt, on October 1, 1956. He received the BSEE, MSEE, and Ph.D. degrees from the University of Kansas, Lawrence. in 1978, 1981, and 1984 respectively. He is currently working for E-Systems Corpora-tion. ...
IEEE Transactions on Antennas and Propagation, 1986
Absrrccr-A general approach is presented for the determination of power radiated via the space wa... more Absrrccr-A general approach is presented for the determination of power radiated via the space wave and surface wave from the aperture of an arbitrarily shaped microstrip antenna. The magnetic current model is used for this, and the analysis is carried out in the Fourier domain to ...
This three part serial discusses basic design considerations for microwave integrated circuits us... more This three part serial discusses basic design considerations for microwave integrated circuits using distributed circuit approach. Various circuit elements include transmission line sections, coupled line section, resonators, junctions, bends, transitions etc. Design data for these elements is included. Of these elements, Part 1 presents available transmission line sections and coupled line sections. Part 2 includes resonators, various discontinuities and transitions.The design method of microwave integrated circuit is illustrated by considering three examples: a pin diode phase shifter, a Gunn oscillator and a hybrid branchline directional coupler. The role of discontinuity and junction reactances in the exact design of these circuits is emphasized. This portion constitutes last part of the serial.
It is shown that a line-length less than quarter wave may be used to match certain complex impeda... more It is shown that a line-length less than quarter wave may be used to match certain complex impedances to a real value. Bowman's results have been developed to achieve this and to plot the forbidden range of impedances on a Smith Chart.
This paper reviews various design formulae for a microstripline. It is pointed out that formulae ... more This paper reviews various design formulae for a microstripline. It is pointed out that formulae chosen for the design need not be more accurate than the limitations imposed by fabrication tolerances.
Closed-form expressions for various types of discontinuities in microstrip, viz. open ends, gaps,... more Closed-form expressions for various types of discontinuities in microstrip, viz. open ends, gaps, step in width, right-angle bend, T-junction and cross-junction, are derived by curve-fitting the available data. The reported expressions are accurate to within 5% in the range of parameter most commonly used. These results save computer time and may be useful in the computer-aided design of microwave integrated
A new type of leaky wave called a alow leaky wave is reported. The slow leaky waves have a phase ... more A new type of leaky wave called a alow leaky wave is reported. The slow leaky waves have a phase velocity less than the velocity of light but radiate in a direction away from end-fire. This type of wave ia supported by a metal-dielectric-thin conductor plate when
Closed form capacitance expressions for the even and odd mode characteristics of coupled microstr... more Closed form capacitance expressions for the even and odd mode characteristics of coupled microstrip lines are presented. These expressions are accurate to within 3% for 0.2≤W/h≤2, 0.05≤S/h≤2 and ϵrl. Extension of these results to asvmmetriu coupled microstrip lines indicate an accuracy of about 5% for ϵ = 10, W/h = 0.95, W2/h≥0.2and S/h≥0.1
IEEE Transactions on Microwave Theory and Techniques, 1978
... and Slotline Performances RAMESH GARG AbstractThe change in characteristics of atransmission... more ... and Slotline Performances RAMESH GARG AbstractThe change in characteristics of atransmission line due ... rev ed, New Delhi, India: Tata McGraw-Hill, 1974, ch 7, pp. 165-174 I J. Bahl and Ramesh Garg. Simple and accurate formulas for ...
IEEE Transactions on Antennas and Propagation, 2003
We have achieved 50 Ω input impedance for edge-fed narrow microstrip square-ring antennas by usin... more We have achieved 50 Ω input impedance for edge-fed narrow microstrip square-ring antennas by using the circumferential variation of current on the ring. The reference point for the current distribution has been fixed by loading the ring. The antenna has been modeled as a lossy transmission line to determine the variation of resonant frequency and input impedance with load. This
A new approach for reducing mutual coupling between planar inverted-F antennas (PIFAs) is propose... more A new approach for reducing mutual coupling between planar inverted-F antennas (PIFAs) is proposed. The approach consists of placing a resonator in between the PIFAs. The signal from the first antenna is scattered by the resonator and couples to the second antenna creating another path for mutual coupling, the phase and amplitude of which may be varied to suppress the existing coupling between the antennas. The simulation and experimental studies show that the proposed technique is able to reduce mutual coupling to about 225 dB from 23.5 dB when the antennas are placed as close as l/11. Reduced mutual coupling between closely spaced antennas may find applications in MIMO, multi-antenna systems and phased arrays.
DHT and two ^N-point DHTs, the JV-point DHT then being obtained by successive use of such decompo... more DHT and two ^N-point DHTs, the JV-point DHT then being obtained by successive use of such decompositions up to the last stage, which is different. The expected speed of a specially written split-radix FHT would be within a few per cent of that of a comparable radix-4 Hartley transform, 1-5 provided that the data sequence was of length N = 16, 64,..., where log 2 N is even. However, for N = 32, 128,..., the radix-4 program is inapplicable, and the standard radix-program is substantially slower than the radix-4.
Annular sector and circular sector microstrip antennas have been analyzed for input impedance and... more Annular sector and circular sector microstrip antennas have been analyzed for input impedance and radiation patterns. The analytical technique used is the generalized transmission line method which has the advantage of estimating the phase of aperture ...
DISCLAIMER OF WARRANTY The technical descriptions, procedures, and computer programs in this book... more DISCLAIMER OF WARRANTY The technical descriptions, procedures, and computer programs in this book have been developed with the greatest of care and they have been useful to the author in a broad range of applications; however, they are provided as is, without ...
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