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Showing papers on "Reflective array antenna published in 1989"


Book
01 Jan 1989
TL;DR: Analysis and design of circular microstrip elements micro Strip patch antennas circular polarization and bandwidth electromagnetically coupled dipoles multilayer configurations large bandwidth hybrid flat dipoles and arrays numerical analysis of microstrip patch antennas segmentation and desegmentation methods for microstrip antenna design transmission line model.
Abstract: Analysis and design of circular microstrip elements microstrip patch antennas circular polarization and bandwidth electromagnetically coupled dipoles multilayer configurations large bandwidth hybrid flat dipoles and arrays numerical analysis of microstrip patch antennas segmentation and desegmentation methods for microstrip antenna design transmission line model of microstrip antennas design and technology of low cost printed antennas analysis and design considerations of printed array antennas circularly polarized array antennas microstrip antenna feeds advances in substrate technology special measurement techniques for printed antennas CAD of microstrip and triplate systems resonant microstrip antenna elements and arrays applications of microstrip antennas monolithic conical conformal microstrip tracking antenna extensions and variations of the microstrip antenna concept.

1,501 citations


Proceedings ArticleDOI
Isamu Chiba1, K. Hariu1, S. Sato1, S. Mano1
26 Jun 1989
TL;DR: In this paper, a method for the analytical determination of the amplitude distribution providing the low sidelobe pattern of conformal array antennas is presented. Butler et al. proposed a projection method that considers both the nonuniform element density and element patterns on the aperture.
Abstract: The authors present a novel method for the analytical determination of the amplitude distribution providing the low sidelobe pattern of conformal array antennas. The proposed projection method considers both the nonuniform element density and element patterns on the aperture. Numerical results are given as well as results of experimental verification for an X-band, half-spherical array with 60 rectangular microstrip antennas. >

39 citations


Patent
23 Jun 1989
TL;DR: In this paper, a dual polarised phased array antenna is formed by intersecting two parallel sets of circuit boards (11,12) respectively carrying orthogonally polarised antenna elements (17).
Abstract: A dual polarised phased array antenna is formed by intersecting two parallel sets of circuit boards (11,12) respectively carrying orthogonally polarised antenna elements (17). In prior antennas corresponding orthogonal elements mutually coincided with board intersections and interengagement slots restricted on-board circuit interconnection of elements. In the improvement the elements (17) are spaced from the board intersection slots (14) facilitating circuit interconnection along the board. Also the phase centres (16) of those antenna elements (17) relating to one polarisation direction are offset from the phase centres of corresponding antenna elements relating to the other polarisation direction. An array employing Vivaldi slot antenna elements is described

18 citations


Proceedings ArticleDOI
01 Oct 1989
TL;DR: In this article, a multiple beam microstrip patch array is presented that combines the function of a beamformer and an array into one structure that gives a one dimensional beam set, and the array comprises a set of series resonant patch arrays that are excited by a number of travelling wave feed lines.
Abstract: A novel multiple beam microstrip patch array is presented that combines the function of a beamformer and an array into one structure that gives a one dimensional beam set. The array comprises a set of series resonant patch arrays that are excited by a number of travelling wave feed lines. The beam directions are determined by small meander line phase shifting sections in each feed line. In this paper the array operation is described and the behaviour of the radiation pattern, gain, bandwidth and beam isolation are noted. Measured results for a 5 beam array at 8 GHz are given. The array gives significant simplification over other current multiple beam antennas and has potential use in several current application areas.

8 citations


Proceedings ArticleDOI
26 Mar 1989
TL;DR: A multiple-target-detection technique based on phase processing of data collected in a sequential mode operation is presented, and the attenuation of the secondary patterns is not sufficient because the diameter of the dish is limited by the element spacing.
Abstract: A multiple-target-detection technique based on phase processing of data collected in a sequential mode operation is presented. The elements are assumed to be circular dishes. No tapering or phase-shifting hardware is needed. The firing of the elements is sequential with all or some of the elements receiving in parallel. The sequential operation and phase processing applied to a real array show a significant improvement in the array pattern. However, the attenuation of the secondary patterns is not sufficient because the diameter of the dish is limited by the element spacing. the secondary patterns can be reduced to an acceptable level using bistatic arrays. In the present application, the bistatic array consists of two adjacent linear arrays: one transmitting array with large dishes and spacing, and a receiving array with small dishes and spacing. >

7 citations


18 Sep 1989
TL;DR: In this article, the fundamental principles of a phased array are described and the properties of radiating apertures are given first, as these are basic to both aperture antennas and arrays as sampled aperture.
Abstract: Phased arrays are a major class of antennas which offer many important features such as electronic beam scanning. Their flexibility has to be assessed against their complexity and cost. The fundamental principles of a phased array are described. The properties of radiating apertures are given first, as these are basic to both aperture antennas and arrays as sampled apertures. Linear array analysis then introduces beam steering and null steering. Array beamforming shows how array excitation is controlled. This is followed by discussion of the effects of systematic or random excitation errors. Planar array analysis includes different array grid structures and the important topic of mutual coupling. Finally active arrays are briefly introduced.

7 citations


Book
01 Jan 1989
TL;DR: In this article, the authors present a survey of antennas for surveillance and electronic warfare receivers. But their focus is on four types of antennas: reflector, lens, horn, and other antennas of conventional configuration.
Abstract: Transmission Lines. Transmission--Line Discontinuities. Filters, Hybrids and Couplers, Power Combiners, and Matching Networks. Cavities and Resonators. Ferrite Control Components. Microwave Surface Acoustic Wave Devices. Quasi--Optical Techniques. Components for Surveillance and Electronic Warfare Receivers. Microwave Measurements. Antennas I: Fundamental and Numerical Methods. Antennas II: Reflector, Lens, Horn, and Other Microwave Antennas of Conventional Configuration. Antennas III: Array, Millimeter Wave, and Integrated Antennas. Antennas IV: Microstrip Antennas. Index.

5 citations



Proceedings ArticleDOI
26 Jun 1989
TL;DR: In this article, a theoretical investigation showed that, by using array elements operating at two or more azimuthal modes with circular polarization, the element patterns can be shaped and scanned.
Abstract: A theoretical investigation shows that, by using array elements operating at two or more azimuthal modes with circular polarization, the element patterns can be shaped and scanned. The beam shaping reduces the grating lobe effects and enhances the array gain for large scan angles. As an application of these elements in a phased array, the case of a circular seven-element array is investigated. >

5 citations


Proceedings ArticleDOI
26 Jun 1989
TL;DR: In this paper, the effects of a dielectric cover on the characteristics of circular and annular ring patch antennas are investigated, and the theoretical results are derived from the conventional Hankel transform analysis.
Abstract: A dielectric cover is usually added on top of a microstrip antenna to protect the antenna from environmental damage. The effects of a dielectric cover on the characteristics of circular and annular ring patch antennas are investigated. The theoretical results are derived from the conventional Hankel transform analysis. Some experimental data are also obtained to verify the theory. In general, it is found that when the thickness of the cover is increased, the resonant frequency decreases monotonically. It is also observed that the half-power bandwidth only changes slightly with the superstrate thickness. >

5 citations


21 Nov 1989
TL;DR: In this article, two novel optical techniques are proposed for controlling phased array antennas. First a "nondispersive prism", controlling time-shared single beams or monopulse patterns, and then a "lens-fed model array", which can control multiple independent antenna beams.
Abstract: Two novel optical techniques are put forward, for controlling phased array antennas. First a 'nondispersive prism', controlling time-shared single beams or monopulse patterns. Next a 'lens-fed model array', which can control multiple, independent antenna beams.

04 Apr 1989
TL;DR: In this article, Gaussian beam theory is applied to reflector antenna design and a suggested method for generalising inverse square law factors in a mixed Gaussian-ray geometry is illustrated.
Abstract: Procedures for applying Gaussian beam theory to reflector antenna design are discussed, and a suggested method for generalising inverse square law factors in a mixed Gaussian-ray geometry illustrated. These methods allow practical designs to be generated with almost negligible computation, in unusual geometries. In the practical elliptical antennas described, Gaussian beam concepts have led to a single-lens configuration, involving a real imaged waist in one plane. >



Proceedings ArticleDOI
11 Jun 1989
TL;DR: There is little difference in the throughputs of the four schemes for operation in the normal range of channel traffic levels, and the optimum scheme is compared with three suboptimum, but easier-to-implement schemes.
Abstract: The performance of a number of antenna selection schemes in a multisector packet radio network is analyzed. In the model studied, it is assumed that the mobiles are symmetrically distributed within a circle centered at the base station. The circle is divided into M sectors. The station has M directional antennas, each aiming at one sector. Also available at the station are N/sub r/ receivers. Channel access time is divided into slots. At the beginning of a time slot, N/sub r/ antennas are selected and connected to the receivers. Once made, such connections last until the end of the time slot. The optimum scheme is compared with three suboptimum, but easier-to-implement schemes. It is found that for operation in the normal range of channel traffic levels, there is little difference in the throughputs of the four schemes. >

01 Jul 1989
TL;DR: An overview of recent advances in performing rf measurements on large antennas is presented with emphasis given to the application of a space-based far-field range utilizing the Space Shuttle in this article.
Abstract: Antennas in the range of 20 meters or larger will be an integral part of future satellite communication and scientific payloads. In order to commercially use these large, low sidelobe and multiple-beam antennas, a high level of confidence must be established as to their performance in the 0-g and space environment. It is also desirable to compensate for slowly varying surface distortions which could results from thermal effects. An overview of recent advances in performing rf measurements on large antennas is presented with emphasis given to the application of a space-based far-field range utilizing the Space Shuttle. The concept of surface distortion compensation is discussed by providing numerical and measurement results.

Proceedings ArticleDOI
26 Jun 1989
TL;DR: In this paper, an analysis and design procedure for an array of patches that are coupled electromagnetically by means of microstrip line sections embedded within the substrate is presented, with a simple feed mechanism, with only the first and last patches fed actively or terminated with a load.
Abstract: Analysis and design procedures are presented for an array of patches that are coupled electromagnetically by means of microstrip line sections embedded within the substrate. Such an array has a simple feed mechanism, with only the first and last patches fed actively or terminated with a load. In the design procedure the geometry of the embedded line sections is determined in order to excite a specified set of patch currents and produce a specified pattern. A four-element array having a uniform amplitude taper and a 45 degrees beam was designed and built. >

11 Dec 1989
TL;DR: In this article, the authors investigate the applicability of the EBS tracking technique to the land-mobile satellite terminals using small tracking antennas, and investigate the error detection capabilities of the systems and operational performance of two forms of prototype antenna.
Abstract: The current interest in land-mobile satellite terminals, using small tracking antennas, has prompted researchers at the University of Bristol, to investigate the applicability of the electronic beam squint (EBS) tracking technique to this environment. The preliminary findings of this investigation are presented. Two systems, are described, based on the EBS technique, which use both conventional waveguide and phased array technology. Results are presented covering the error detection capabilities of the systems and operational performance of two forms of prototype antenna. The described schemes are intended for use at L-band and Ku-band. >

Proceedings ArticleDOI
S.M. Ibrahim1
26 Jun 1989
TL;DR: In this article, the analysis of some special cases of finite-element antenna arrays such as V-array, double-V array, and multiple-ring array is presented, and the derivation of the far-field array factor and electric field are given for each case.
Abstract: The author presents the analysis of some special cases of finite-element antenna arrays such as V-array, double-V array, and multiple-ring array. The derivation of the far-field array factor and electric field are given for each case. Some important properties such as the half-power beamwidth, the beamwidth between first nulls (or minimum), and the side-lobe level are given. As an illustrative example, the author considers the case of a 64-element multiple-ring planar array. >

18 Sep 1989
TL;DR: Attention is focussed on the receiving function of the array, since this is generally more demanding in terms of the number of beams to be generated and their sidelobe performance than the transmit function.
Abstract: With recent developments, the array designer now has the option of placing active elements at the array face for both transmit and receive functions, and to perform digitally programmable operations on the signals at each element. The spatial filtering functions required of the array; and the techniques and architectures which are available for their realisation are examined. Attention is focussed on the receiving function of the array, since this is generally more demanding in terms of the number of beams to be generated and their sidelobe performance than the transmit function.

04 Apr 1989
TL;DR: In this paper, the results of an investigation carried out to develop microstrip body-mounted antennas designed to have an omnidirectional radiation pattern in azimuth, at a frequency within the 100-440 MHz range.
Abstract: Presents the results of an investigation carried out to develop microstrip body-mounted antennas designed to have an omnidirectional radiation pattern in azimuth, at a frequency within the 100-440 MHz range. Among the body-mounted antennas tested were a single rectangular patch microstrip antenna, an array of two rectangular patch antennas and a novel, helmet-mounted travelling-wave microstrip antenna. >

Proceedings ArticleDOI
01 Oct 1989
TL;DR: In this article, an integrated multi-channel, multi-frequency microstrip antenna array with a given limited aperture is described. But the performance of the array is limited by the number of microstrip patches that can operate at different frequencies.
Abstract: This paper describes an integrated, multi-channel, multi-frequency microstrip antenna array confined to a given limited aperture. Integration of several channels has become important in the development of wide scan angle phased-array antennas that operate without the appearance of grating lobes. The integrated array presented here is built from special multi-channel microstrip elements. Each element of the array consists of microstrip patches operating at different frequencies which are integrated into one microstrip element. This unique technique reduces the weight and dimensions of the multi-channel array, compared to that of separated arrays with the same performance.

Proceedings ArticleDOI
26 Jun 1989
TL;DR: In this article, the authors describe the eight different types of antennas on the INTELSAT VII spacecraft, which are: (1) C-band hemi/zone antennas, (2) Cband spot antenna, (3) Ku-band spot antennas,(4) global antenna, and (5) K-band beacon antenna.
Abstract: The authors describe the eight different types of antennas on the INTELSAT VII spacecraft. These antennas are: (1) C-band hemi/zone antennas, (2) C-band spot antenna, (3) Ku-band spot antennas, (4) C-band global antenna, (5) Ku-band beacon antenna, (6) C-band beacon antenna, (7) omni telemetry tracking and control antennas, and (8) telemetry directional antenna. All antennas are located on the earth panel of the satellite except the hemi/zone antennas, which are on the east and west sides of the spacecraft. All antennas have a clear view of earth with 'stay-away' regions to eliminate any scattering-related performance degradation. >

04 Apr 1989
TL;DR: In this paper, the authors presented a miniaturized log-periodic dipole array using a meander element for each dipole arm, which consists of a zig-zag path intended to reduce the resonant length.
Abstract: The author presents a miniaturized log-periodic dipole array using a meander element for each dipole arm. A meander section consists of a zig-zag path intended to reduce the resonant length. By this technique a 35 percent reduction in size is obtained for the dipole elements of the array. The miniature array is compared with the full-size version, and an overview of size reduction methods is given.

Proceedings ArticleDOI
26 Jun 1989
TL;DR: In this article, a 90 degrees corner reflector antenna was developed to meet the design requirements of the required bandwidth, front-to-back ratio, and low feedover were achieved by using triangular flat-blade dipole elements (resistively terminated) and filling the antennas with titanium dioxide (TiO/sub 2/) powder.
Abstract: A promising technique being developed for probing coal seams (3 m thick) ahead of the cutting face is to drill a horizontal borehole midway through the seam in which a ground-penetrating FM radar probe can be inserted to measure the seam thickness and to detect the presence of faults. For this application, the radar antennas (bistatic system) must be broadband and directional, operate in the VHF/UHF bands, and fit within a borehole diameter of approximately 4 inches (10.2 cm). A 90 degrees corner reflector antenna was developed to meet the design requirements. The required bandwidth, front-to-back ratio, and low feedover were achieved by using triangular flat-blade dipole elements (resistively terminated) and by filling the antennas with titanium dioxide (TiO/sub 2/) powder. Performance results are presented and discussed. >

23 Jan 1989
TL;DR: In this article, the authors used an array of log-periodic dipole antennas (LPDAs) for wideband wideband applications, based on extensions of the principles established by Hill and Koepke.
Abstract: Compact ranges have traditionally used reflector antennas for illumination, but these are typically only usable at high frequencies, such that the reflector is a substantial number of wavelengths in width. For lower frequencies, control of the aperture illumination is better achieved by using an array antenna. Some numerical antenna pattern synthesis methods, stemming from the more generalised 'regularisation methods', derived by Mautz and Harrington (1975), are suitable for synthesising antenna patterns in the near field as well as the far field. The design procedures discussed are based on these methods. Similar work has been reported by Hill (1985) and Koepke (1986) who designed and built an array of seven Yagi-Uda antennas for an experimental compact range. In order to investigate the criteria for use of the array in wideband applications, the work reported used an array of log-periodic dipole antennas (LPDAs) and was based on extensions of the principles established by Hill. >

04 Apr 1989
TL;DR: In this paper, a technique has been developed to transform near field measured data back to the apertures of a linear aperture array, which was initially created for the characterization and iterative development of this linear array.
Abstract: A technique has been developed to transform near field measured data back to the apertures of a linear aperture array. The technique described was initially created for the characterization and iterative development of this linear array. The technique is offered as a superior replacement to reactive nearfield probing.

Proceedings ArticleDOI
26 Jun 1989
TL;DR: In this article, a procedure for deriving the expectation and variance of the two-dimensional array pattern when the array uses Tseng window weight for its gain at each element is presented.
Abstract: The authors observe how the errors in location of the elements of a two-dimensional antenna array affect the gain pattern of the array in a statistical manner. A procedure for deriving the expectation and variance of the two-dimensional array pattern when the array uses Tseng window weight for its gain at each element is presented. By computing the expectation, variance, and deviation of the array pattern, the critical value for the position error can be determined depending on the desired sidelobe level of the array. Numerical results are presented. >

Proceedings ArticleDOI
26 Jun 1989
TL;DR: In this article, it is considered that the radiation field of an end-fed circular array, whose main beam points toward the array normal and whose elements are uniformly spaced in the circle, is the output of a time-invariant system.
Abstract: It is considered that the radiation field of an end-fed circular array, whose main beam points toward the array normal and whose elements are uniformly spaced in the circle, is the output of a time-invariant system. On the basis of a linear system, the transfer function of this system is obtained. The time required for the establishment of the steady-state pattern is assessed. >

15 May 1989
TL;DR: A new analysis approach is introduced that considers the presence of the BWG enclosure and has revealed new understandings of the performance degradation mechanisms in a BWG antenna and provided direction for potential design improvements.
Abstract: Beam-waveguide (BWG) antennas provide multiple frequency band operations and other operational benefits for large ground-station antennas. Present design practices use diffraction analyses that ignore the presence of the BWG enclosure and may be inaccurate at lower frequency bands for ground-station antennas operating over multiple frequency bands. Introduced here is a new analysis approach that considers the presence of the BWG enclosure. Results based on the new analysis have revealed new understandings of the performance degradation mechanisms in a BWG antenna and have provided direction for potential design improvements.