Papers by Khair Al Shamaileh
A half‐mode substrate integrated waveguide filtering power divider with Fourier‐varying via holes
Microwave and Optical Technology Letters
IEEE Access
In this article, an optimization-driven methodology is proposed for the design of substrate integ... more In this article, an optimization-driven methodology is proposed for the design of substrate integrated waveguide (SIW) bandpass filters (BPFs) with predefined passbands. The width between the metallic walls of via-holes is governed by a truncated Fourier series to achieve the desired filtering performance. The theory of rectangular waveguide is used to establish the optimization framework and obtain the series coefficients under predefined physical constraints. Two types of end-terminations are studied; specifically, with and without SIW-to-microstrip transitions. To validate the proposed methodology, two Ku-band BPF prototypes with 2.5% and 5.8% 15-dB fractional bandwidth (FBW) are designed, simulated, and measured. Furthermore, the half-mode SIW (HMSIW) concept is incorporated in one prototype to facilitate a miniaturized physical structure. Simulations and measurements are in close proximity with passband matching and transmission losses better than-15 dB and-2.5 dB, respectively. The proposed methodology allows for designing BPFs with predefined wideband or narrowband FBW by modifying the underlying physical constraints and optimization parameters. The resulting filters are planar, compact, and have wide stopband rejection. In addition, a derivation for the characteristic impedance of the SIW line is provided, which can be used to find the optimum SIW-to-microstrip transition without performing a parametric study. INDEX TERMS Bandpass filter (BPF), half-mode substrate integrated waveguide (HMSIW), SIW-to-microstrip transition, narrowband, rectangular waveguide, substrate integrated waveguide (SIW), wideband.
A miniaturized ultra-wideband Wilkinson power divider using non-uniform coplanar waveguide
Proceedings of the 1st International Congress on Engineering Technologies
A Defense Mechanism against Replay Attack in Remote Keyless Entry Systems Using Timestamping and XOR Logic
IEEE Consumer Electronics Magazine
Link-Signature-Based Discriminatory Channel Estimation (LS-DCE) for Physical Layer Security in Stationary and Mobile OFDM Transceivers
IEEE Transactions on Vehicular Technology
Multi-section branch-line crossover/coupler optimization for wideband applications and higher-order harmonics suppression
AEU - International Journal of Electronics and Communications
Design of multi-band miniaturized Bagley power dividers based on non-uniform coplanar waveguide
AEU - International Journal of Electronics and Communications
IEEE Access
The establishment of convenient and reliable cryptographic keys is not always feasible, especiall... more The establishment of convenient and reliable cryptographic keys is not always feasible, especially in low-powered wireless devices where a complex key management infrastructure is unaffordable. Physical layer-based key generation approaches, on the other hand, allow two legitimate users to establish a common secret key by exploiting the parameters of the wireless channel, such as the underlying impulse response. In this paper, a fundamental bound on the maximum achievable key generation rate (KGR) over wireless fading channels with asymmetric additive white Gaussian noise (AWGN) is derived. A Nakagamim fading channel is considered, and the effect of non-reciprocity on the forward and reverse channels correlation is demonstrated. We validate the theoretical platform through simulations using a key generation protocol based on the level crossing rate (LCR) of the fading process. The proposed LCR protocol models the Nakagami channel by utilizing the sum-of-sinusoids approach, where Doppler shift, fading severity, and number-of-paths are taken into account. The proposed protocol also incorporates a two-level quantizer to extract keys, where the channel estimates between a wireless transmitter and receiver can be used as the basis. Besides providing an upper bound on the KGR, the analytical and simulation results intertwine the effect of channel reciprocity with the key generation process. INDEX TERMS Information-theoretic security, key generation rate (KGR), level-crossing rate (LCR), Nakagami-m fading, physical layer security (PLS), reciprocity, wireless channel.
General Design Equations For 3-way Unequal-split Bagley Power Dividers
IET Microwaves, Antennas & Propagation
Miniaturized Dual-Band CPW Wilkinson Power Divider Using T-Network Adopting Series Stubs with a High Frequency Ratio
AEU - International Journal of Electronics and Communications
Progress In Electromagnetics Research M
In this paper, we systematically derive design equations for 3-way Bagley power dividers with arb... more In this paper, we systematically derive design equations for 3-way Bagley power dividers with arbitrary split ratios using interconnecting transmission lines with the same characteristic impedance. The exact value of the characteristic impedance for a specific dividing ratio is determined using these equations to achieve perfect input port matching. To validate the design procedure, two microstrip dividers with different split ratios, 1 : 3 : 1 and 1 : 10 : 1, are designed, simulated, fabricated, and measured. The desired split ratios are achieved at the design frequency, 1 GHz. Good agreement between simulated and measured results is obtained.
Width-varying Conductor-backed Coplanar Waveguide-based Lowpass Filter with a Constant Signal Trace to Adjacent Grounds Separation
IET Microwaves, Antennas & Propagation
Miniaturized multi-frequency Wilkinson power dividers based on nonuniform coplanar waveguide
International Journal of RF and Microwave Computer-Aided Engineering
A compact coplanar waveguide Wilkinson power divider based on signal traces and adjacent grounds width modulation
Microwave and Optical Technology Letters
General design of impedance-varying multi-way Wilkinson power divider with bandwidth redefinition characteristics
International Journal of RF and Microwave Computer-Aided Engineering
A Dual-Band 1:10 Wilkinson Power Divider Based on Multi-T-Section Characterization of High-Impedance Transmission Lines
IEEE Microwave and Wireless Components Letters
2016 88th ARFTG Microwave Measurement Conference (ARFTG), 2016
We propose a compact wideband multi-way power divider/combiner with planar structure for applicat... more We propose a compact wideband multi-way power divider/combiner with planar structure for applications to RF power amplifiers (PAs). Uniform transmission lines in the conventional divider are replaced with non-uniform transmission lines (NTLs), which are governed by a truncated Fourier series. An optimization-driven framework is employed in even-mode analysis to obtain the coefficients of the NTLs considering predefined operating bands, whereas three isolation resistors are optimized in the odd-mode analysis to achieve optimal isolation and output port matching over the design bandwidth. For verification purposes, a 4-10 GHz 3-way divider is simulated, and measured. Simulations and measurements are in close proximity and show input/output ports matching of better than-10 dB and transmission of-4.9 ±1 dB across the design bandwidth. Index Terms-multi-way power divider, non-uniform transmission lines (NTLs), power amplifiers (PAs), power combiner, wideband Wilkinson power divider (WPD).
Multiway wideband power dividers
International Journal of RF and Microwave Computer-Aided Engineering, 2015
ABSTRACT
Impedance-Varying Broadband 90° Branch-Line Coupler With Arbitrary Coupling Levels and Higher Order Harmonic Suppression
IEEE Transactions on Components, Packaging and Manufacturing Technology, 2015
ABSTRACT
Progress In Electromagnetics Research C, 2015
A new miniaturization methodology suitable for printed linear antennas is presented. Miniaturizat... more A new miniaturization methodology suitable for printed linear antennas is presented. Miniaturization is accomplished by replacing a linear radiator element of a conventional antenna with a compact continuously varying-impedance profile governed by a truncated Fourier series. A design example of a printed half-wavelength dipole antenna is designed and realized in microstrip technology. The performance of the proposed antenna is compared with its equivalent uniform dipole to highlight the performance equivalency. With a 25% reduction in the dipole arm length, both antennas show a measured peak gain and a fractional bandwidth of 5.4 dBi and 16%, respectively at 2.5 GHz; hence, the overall electrical performance is preserved. It will be shown that the design procedure is systematic and accurate. The proposed approach has potential for achieving advanced frequency characteristics, such as broad-and multi-band antenna responses.
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Papers by Khair Al Shamaileh