The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The analysis of the tolerance effects on the radiated power pattern caused by the fabrication errors in the printing of the microstrip patches of reflectarrays is addressed through a method based on the Interval Analysis and the arithmetic of intervals. The dimensions of the microstrip patches are defined as intervals of values including the tolerance errors and the mathematics of intervals is exploited...
In this paper, a four element coplanar waveguide fed monopole antenna which is arrayed as volume array antenna to obtain omnidirectional pattern is presented. This femtocell antenna is designed to work at frequency 2.3-2.5 GHz for VSWR <2 and have at least 100 MHz impedance bandwidth. This array antenna has low mutual coupling, 460 MHz bandwidth at frequency 2.05-2.51 GHz and gain 6.3 dBi.
The wideband printed antenna array with cosecant square-shaped beam pattern, synthesized using Orchard Elliott's methods and genetic algorithm, is proposed. The array is with four symmetrical pentagonal dipoles as radiating elements operating at a second resonance. The apex of corner reflector is at distance λ0/2 from antenna array increasing antenna gain. The symmetrical tapered feed network of impedance...
Four-element microstrip patch antenna array is proposed at millimeter wave frequency. The proposed antenna achieves the impedance bandwidth of 4.6% at 28 GHz as well as a flat gain of 13.5 dB over an operating frequency band. It uses the aperture coupling along with air cavities to feed the patch elements. It achieves the side lobe level of -23 dB in the H Plane and -14.5 dB in the E plane. In addition,...
A compact reconfigurable defected microstrip structure (RDMS) unit is proposed for phase shifters used in phased array antennas. The RDMS unit can introduce a phase shift when working in two different states. The performance of the RDMS unit, including the phase shift and insertion loss, is found to have closely correlations with some key dimensions, which is elucidated using equations and simulations...
A wideband planar microstrip grid array antenna is presented. The antenna is realized on a standard Rogers RO3003 substrate. It is fed using two centrally located microstrip vias through a ground aperture. Measured results show a 12% S11 <−10 dB bandwidth and a maximum gain of 17 dBi. Using a variable microstrip line width, a side-lobe suppression of at least −12 dB between 77–85 GHz is measured...
For linear multi-pixel imaging systems, a linear stack of pixels comprising of an antenna and a heterodyne receiver are needed. Such pixels can be realized using MMIC processes. The main constraint for such multi-pixel system is a compact array of pixels giving high coupling to quasi-optics used for focusing. This paper addresses this trade-off and presents a novel solution based on beam synthesis...
In this paper, carried out research on the development of radar antenna for X-band, with a resonant frequency of 9.4GHz. Antenna designed using coplanar array, the module is designed radiating patch of 4, 4 co-planar patch on the left side of the main and 4 co-planar on the right side of the main patch. Bandwidth resulting from the simulation is 677.8MHz, at a frequency of 9.0815GHz – 9.7953GHz. In...
Models of the cylindrical microstrip phased antenna arrays (MPAA) of rectangular radiators on the thin suspended anisotropic substrate are examined. Radiation and scattering characteristics of MPAA in the X-band are studied numerically in HFSS. Possibilities of a controlling of the scattering characteristics of "MPAA-cylinder" system by means of switching the states of its passive reciprocal...
A novel compact microstrip-to-waveguide transition is presented. In this structure, the backshort is surrounded by metal vias and integrated with a multilayered circuit board. The bottom of the backshort is formed by an array of metal blind vias with periodic structure. An air blind via array is drilled into the substrate within the backshort. Therefore the cross-section dimensions of the backshort...
As the mutual coupling effects play a major role in synthesizing of array, it needs to be investigated. This paper discusses the process of computing the mutual coupling among rectangular patch antenna elements (RPAE) conformed onto a hemisphere surface. The elements are arranged in two different distributions, mainly E- and H-plane type. The isolated mutual coupling is considered in an array which...
Digital beam forming has been implemented in a 7T MRI system with a multi-channel RF coil to obtain images with optimized signal to noise ratio, and uniform intensity. Beam forming is performed by summing the complex images received at each pixel in the image plane using a weighting algorithm to optimize the signal to noise ratio. The theory developed for the algorithm is outlined and includes the...
This paper presents design of a microstrip antenna array fed by transverse slots on a broad wall of the rectangular waveguide with standing wave excitation for linear polarization parallel to the axis. A series-fed two-element microstrip antenna array on a dielectric substrate excited by a transverses slot of the waveguide is used as an element of the proposed array. In this paper, radiation power...
This paper presents a new broadband antenna for satellite communications. It describes the procedure involved in the design of a microstrip antenna array and its multi-level passive feed network that together yield circular polarization and the necessary gain to be used in an earth-satellite link. The designed antenna is notable for its large bandwidth, circular polarization, high gain and small dimensions.
In this paper, we verified the Poggio, Miller, Chang, Harrington, Wu and Tsai - Characteristic Basis Function Method (PMCHWT-CBFM) by applying the extended version of the CBFM for analyzing the radar cross section (RCS) of the array antenna. The method can be reduced memory usage of calculation compared with those of the direct MoM.
A 4 × 2 microstrip antenna array has been proposed, in which the broadside beam is obtained in a wide frequency range. The broadband operation is achieved with the use of a 4-way slot-coupled power divider which not only performs wideband 180-deg phase shift, but also preserves the symmetry of an antenna array. The paper includes detailed design description as well as simulation and measurement results...
Floquet analysis is applied to study the effects of incident angle on the reflection properties of unit cells. The performance of reflectarray unit cells is evaluated in terms of reflection loss and phase sensitivity. The analysis is demonstrated in three planes of interest, where extremes in performance are likely to occur. Unit cell illuminated by an incident wave with varying angles of arrival...
Nowadays, radar retro-reflector has been widely applied as a decoy, to seduce an incoming assault away from the target, or towards a less vulnerable part of it to communication systems and remote identification as their characteristics of low-profile, low-cost and Radar Cross Section (RCS) enhancement. A passive retro-reflector is a device which can be used to be reflected most of the energy incident...
In this paper, a novel microstrip antenna array with low RCS (Radar Cross Section) is presented and analyzed. Under the condition that the incident wave is in grazing angle, a single microstrip antenna which uses the techniques of miniaturization and ground-cut slots is chosen as an element of a 2×2 antenna array. Analysis and optimization of the arrangement of the array is made to realize more reduction...
In this paper, with the application of dielectric resonator antennas(DRA), a novel design of a shared-aperture dual-band dual-polarized (DBDP) array working in the Ka/Ku bands is proposed. At Ka-band, aperture-coupled microstrip patches are selected as the radiating elements. At Ku-band, Crossed dielectric resonator antennas(DRA) are selected as the radiating elements. The array which comprises 2×2...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.