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The design, simulation and fabrication of a dual band waveguide structure for the direct broadcast satellite (DBS) market is presented. Using two frequency bands under study; 19.7–20.2 and 29.5–30 GHz, we have created a corrugated waveguide structure with a second higher band waveguide nested inside the outer waveguide. The design and simulation was carried out using CST's Microwave Studio 2010 Suite...
A rectangular strip monopole antenna for use in portable wireless communication applications is presented. The proposed antenna consists of a rectangular radiating patch and a novel impedance transformer in the ground plane and has a compact dimension of 30×12 mm2 on a substrate with permittivity 4.4. The prototype antenna has wide impedance bandwidth from 2.85–14.25 GHz for −10 dB. Stable and omni...
A glottal radar system has been successfully developed to extract human speech information with great immunity to acoustic interference, which enables numerous speech related applications. This work proposed and demonstrated two potential uses. First, for the communication quality enhancement of mobile handsets in a noisy environment, the background acoustic noise can be effectively detected and eliminated...
This paper presents a compact 77-GHz CMOS bandpass filter suitable for single chip integration with an RF transceiver. The CMOS bandpass filter is mainly composed of an open resonator loaded with two grounded pedestal stepped-impedance stubs to enhance the band selectivity and reduce the chip size. The grounded pedestal is constructed from the vertical stack of the multiple metal layers of the CMOS...
We describe in this paper a new technique for measurement of reflection coefficients of high impedances devices in radio frequency (RF). To that end, a system intrinsically high impedance (characteristic impedance = 1 kΩ) based on a multi-port technique is developed. The validation of the approach chosen is made by measuring high value resistors.
The spread of metamaterial concepts has lead to the appearance of waveguides with a composite right/left-handed (CRLH) behavior, i.e., supporting both forward and backward waves, together with a zero-phase-constant wave. The use of this kind of waveguide as feeding structures gives rise to a new generation of slot array antennas, which exhibits new radiation capabilities, such as backward-to-forward...
The six-port network has been identified in recent years as one of the best candidates to implement a Software Defined Radio (SDR). The main characteristic of the six-port architecture is its extremely large bandwidth, which involves multi-band and multi-mode capabilities. However, broadband six-port network designs lead to large size circuits. New technologies must be explored in order to achieve...
Using a GaN high power amplifier and a double 4-inputport circular waveguide combiner, a 1kW S-band compact waveguide combiner unit operating at 2.1 GHz was assembled. The maximum power of 200W was realized with a Peltier device for heat sink. The high power amplifier unit shows the PAE of more than 50% with an AB-class operation under the temperature around 40 degrees C. The four GaN high power amplifiers...
In this paper, an interface between 2-D and 3-D EM simulators is presented for the optimization-oriented design of 3D RF/microwave circuits. This optimization tool is obtained from a linear iterated 2-D to 3-D prediction method and a modeling process based on a fuzzy logic technique. We illustrate the performance of our technique with the design of third-order C-band evanescent rectangular waveguide...
This paper investigates the electrical characteristics of nano-particle-based pulverized materials. A measurement setup is developed to extract the electrical properties of the composite material in its powder form. Numerical simulations are also carried out to examine and analyze the effects of embedded metallic particles in a dielectric host medium. The experimental results present the role of the...
In this work, a very efficient mixed-potential integral-equation formulation is implemented for the rigorous analysis of multilayered structures with arbitrarily-shaped two-dimensional periodic metallic and/or dielectric inclusions. Original acceleration techniques have been developed for the computation of the components of the scalar and dyadic Green's functions, based on different types of asymptotic...
The external modulation, in the optical links, allows us to transmit a great quantity of digital data. With the spectral efficient given by the 16-QAM modulation and the OFDM, near 1 Gb/s transmission link is possible to get in UWB (Ultra-Wide Band). The direct modulation laser seems to be preferred for the radio over fibre (RoF) home and radar applications, due to its simplicity, but the limit in...
To meet the IMT-Advance technical requirement, both 3GPP LTE-Advanced and IEEE 802.16m include carrier aggregation as one of the key RF technologies. Carrier aggregation uses several carriers with narrow bandwidth which will be combined in the upper layer for high data rate transmission. These carriers can be either adjacent to each other or in different bands. This work describes a transceiver architecture...
This paper proves through simulations that current routing protocols recommended for MANETs do not support a realistic marginal mobility model. A WSN scenario is considered using Qualnet simulator in which the mobile node follows the marginal mobility model. It is proven that routing protocols like DSR, AODV, LAR1, DYMO and Bellman Ford can't send data packets to the mobile node. Different simulations...
This paper presents a silicon platform with Through-silicon vias (TSV) interconnects for Radio-Frequency applications, implemented in a via-last integration scheme. As it is aimed at transmitting a wide range of signals, it is mandatory to accurately evaluate frequency dependent loss of TSV. To achieve attractive RF performances, the silicon platform is carried out on High-Resistivity (HR) substrates...
This paper presents a hermetic sealing technique for rectangular waveguides and packages to improve the reliability of systems in the F band (90–140 GHz). The technique features a new sealing structure, which is a laminate composed of two sealing plates and a spacer with a WR-8 waveguide. The sealing plate has the fused glass window and separates inside air from the ambient atmosphere. The laminated...
A compact in-line pseudoelliptic evanescent mode filter for high power and wide spectrum applications is presented in this paper. The filter employs series lumped capacitors between adjacent resonators. Such capacitors are properly combined with the series distributed inductance of the evanescent mode sections so as to provide independently controlled transmission zeros. The proposed approach does...
In this paper, graphics processing unit (GPU) is used to accelerate both the impedance matrix calculation and the linear system solution in a Mixed-Potential Integral-Equation (MPIE) formulation of the method of moments (MoM). We consider a three-step process. First, the MoM matrix is computed on the GPU by using a quasi-one-dimensional approximation of the MPIE formulation. Second, a sparse representation...
Space mapping (SM) is a popular technique that allows creating computationally cheap and reasonably accurate surrogates of EM-simulated microwave structures (so-called fine models) using underlying coarse models, typically equivalent circuits. Here, we consider various ways of enhancing SM surrrogates by exploiting additional training data as well as two function approximation methodologies, kriging...
In this paper, by using microstrip resonators having dual-mode characteristics, a novel dual-band bandpass filter is presented. Designed resonator structures have been formed by placing a couple of open-circuited stubs to the corner points of a square loop resonator. By means of movement of the gaps between the open ends to obtain a perturbation effect, two degenerate modes are excited, mode frequencies...
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