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A novel ultra-wideband (UWB) bandpass filter with improved upper-stopband performance is presented and constituted by integrating an initial UWB filter with two lowpass filters at its two sides. Firstly, a multiple-mode resonator is formed with first three resonant frequencies located within the 3.1-10.6 GHz UWB band while its two-side high-impedance sections are excited by two interdigital coupled...
An ultra wideband bandpass filter (BPF) with sharp-rejection is proposed by using a new structure of double ring resonators. The double ring resonator generates a couple of attenuation poles, and its operation mechanism is made clear through the even- and odd-mode analysis of the circuit. The stopband of the filter can be significantly widened by cascading the double ring resonators. A two-stage microstrip...
The coupled computational intelligence, in term of genetic algorithms and artificial neural networks, with the time-domain solver for design of the microwave devices is presented in this paper, where the coupled genetic algorithms with the time-domain solver is used for optimization and the artificial neural networks is used to surrogate the time-domain solver in design of the microwave components...
The vector finite element method (FEM) is an efficient approach for field computation of complex. By using edge elements, vector FEM is applied to the analysis of an electromagnetic wave propagation tool in the inhomogeneous media. Mainly the influence of the complex environment on the measurements is studied. The influence environmental factors include the fluid medium, the invaded zone, and the...
For the first time, macro-element technology is introduced into the vector finite element method with the perfect matching layer for analyzing 3-D electromagnetic radiation problems. By defining a macro element domain and non-macro element domain inside the finite element domain and transferring the information from the non-macro element domain onto the surface of the macro element domain, the number...
A statistic channel model, TSV-model: Shoji, Sawada, Saleh (Triple S), and Valenzuela model, was newly developed to design 60-GHz band wireless personal area network systems. Shoji and Sawada newly developed a statistic two- path channel model to express sensitive device- position-dependent fading inherent to mmW WPAN system and combined it with the statistic S-V model which had been commonly used...
Simple configuration of RF module is proposed for passive millimeter-wave imaging system. The results of the detector design for the module are reported in this paper. A detector planar circuit and a waveguide horn antenna are connected by broadband microstrip-to-waveguide transition. A number of the antenna is arranged around the focal point of the lens, which results in the proposed RF module. Since...
An ultra-wideband circularly-polarized (CP) microstrip antenna is presented with the introduction of one wideband 90deg feed network. The CP patch antenna experimentally offers a 10-dB impedance bandwidth of 71.7%, 3-dB axial-ratio bandwidth of 81.6% and a gain bandwidth of 52.2% with its highest gain of 8.1 dBi at 1.8 GHz.
Microstrip slot antenna fed by microstrip line with multi tuning stubs to increase the bandwidth is proposed. The microstrip line composed of tuning stubs is used to control microstrip slot antenna real impedance to match with impedance characteristic of feeding line so that it could increase the bandwidth. The proposed antenna design achieves good input impedance in the range frequencies of 1.3 -...
This paper presents a low-cost experimental GSM based passive radar and testing of ground vehicle detection. It describes the system design, signal processing, and field measurement for detecting various ground vehicles. Using this novel passive radar, numerous field experiments for various ground moving targets are extensively explored. Interesting field experiment results were presented to demonstrate...
A novel extended composite right/left-handed (E-CRLH) transmission line (TL) metamaterial structure, constituted by the combination of the conventional CRLH (C- CRLH) and the recently introduced dual CRLH (D-CRLH) prototypes, is proposed. This E-CRLH metamaterial is characterized by eight LC parameters (four C-CRLH and four D-CRLH parameters), which allow unprecedented diversity in the manipulation...
In this paper, a novel single-diode frequency doubler design method is proposed. The output fundamental frequency is suppressed by employing a lambda/2 feed-forward transmission line parallel with a diode instead of using balanced structure with two or more diodes. The deployment of feed-forward line reduces the complexity of matching circuit and the circuit is more compact than doubler circuit without...
In this paper, the miniaturized microstrip interlocked-coupled bandpass filters are proposed. With the proper utilization of folded quarter-wavelength stepped-impedance resonators, the occupied area of coupled-resonator pair may be reduced. In order to introduce two transmission zeros near the passband, an additional open-stub section is inserted between the low- and high-impedance lines of the resonators...
A 2-feed scheme is studied on reducing the noise in packaging due to edge fields in the rectangular power/ground planes. For efficient and accurate prediction of the fields' behavior along the edges of the structure with respect to feeding conditions, a fast single sum is derived to consider loads. Solving example structures will show the differential signaling can improve the problems and be affected...
This paper studies the sources of the short term memory effects exhibited by radiofrequency power amplifiers. Based on this study a multi-branch structure-based predistorter was applied to overcome the inability of the traditional predistortion to compensate for these imperfections. In addition, the identification of the parameters of such structure is investigated and several adaptive algorithms...
Leaky wave radiation from a one- dimensional left-handed transmission line is investigated that is composed of a cut-off parallel plate waveguide loaded with dielectric resonators (DR). The left-handedness is established by the combination of negative effective permittivity due to the cut-off TE parallel plate waveguide mode and negative effective permeability originating from the macroscopic behavior...
In this paper, a free space power combining oscillator antenna array using a metamaterial based injection locking coupling network is described and demonstrated. The unique metamaterial series coupling network utilizes the infinite wavelength phenomenon which allows it to support an infinitely long wave at a non-zero frequency. It is demonstrated that equal phase/amplitude oscillator synchronization...
This paper presents a rigorous analytic approach for the quantization of OFDM signals. The signal-to-noise ratio at the ADC output is derived as a function of the input signal's standard deviation and the ADC input range. Furthermore, the maximum signal-to-noise ratio is calculated for various ADC resolutions. The analytic results are verified by simulations applying an OFDM WLAN signal as well as...
This paper presents radiation characteristics of a finite periodic slot array in a parallel plate waveguide filled with a transversely magnetized ferrite. The characteristics are analyzed by using the moment method and estimated numerically under the condition that the fundamental TE1 mode is only the propagating mode in the unperturbed parallel plate waveguide. It is theoretically explained how the...
A simple high-order predistorter to cancel the 3rd - and 5th -order intermodulation (IM3 and IM5) components of RF power amplifiers is proposed. The IM3 and IM5 components are cancelled out simultaneously by using their identical magnitude and phase difference in the predistorter and power amplifier. For experimental verification, a high-order predistorter has been implemented and tested with a 45-W...
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