Conference Paper

A millimeter-wave conformal phased microstrip antenna array on a cylindrical surface

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Abstract

The work presents a design of a cylindrical conformal phased microstrip antenna array. Based on the HFM and the parallel feed network, a conformal microstrip 2 times 8 array on a cylinder surface is designed by the isotropic transformation theory (IT). Simulation results show that the conformal array works at 35GHz and the gain is 19.6dB at the center frequency. The phase-scanned patterns of the conformal 2 times 8 array are analyzed by the CST using phase control method. From the comparison of the scanning results at different phase division, it can be found that the scan angle, the angular width and the side lobe level varies following the trends of the phase division, at the same time, the gain of the conformal array changes markedly opposite the trends of the phase division. Therefore, this is a shortcoming of the conformal phased array. This kind of conformal phased sub-array can be easily expanded into a large-scale conformal array and be suitable for active integration with other microwave circuits and communication systems if this disadvantage was eliminated after further discussion in future.

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... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Effect of curvature of conformal antenna on resonance frequency been presented by Clifford M. Krowne [13,14] as: (1) where 2b is a length of the patch antenna, a is a radius of the cylinder, 2θ is the angle bounded the width of the patch, ε represents electric permittivity and µ is the magnetic permeability. ...
... For this, substitute Equation (9) into Equation (3) and multiply both sides of (3) by , and integrate over area of the patch. Making use of orthonormal properties of , one obtains: (10) Now, let the coaxial feed as a rectangular current source with equivalent cross-sectional area centered at , so, the current density will satisfy the Equation below: (11) Use of Equation (14) in (13) gives: (12) So, to get the input impedance, one can substitute in the following Equation: ...
... (14) By using Equations (4), (9), (11), (14) and substitute in (13), we can obtain the input impedance for a rectangular microstrip antenna conformal in a cylindrical body as in the following Equation: (15) V. MUTUAL COUPLING Mutual coupling between array elements affects the radiation pattern and input impedances. The radiation from one element in the array induces currents on the other elements to a nearby and scatters into the far field. ...
Chapter
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna. Consequently, the fringing field affects the effective dielectric constant and then all antenna parameters. A new mathematical model for return loss mutual coupling coefficient as a function of curvature for two element array antenna is introduced in this paper. These parameters are given for TM10 mode and using three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass and Epsilam-10 ceramic-filled Teflon. Index Terms— Fringing field, Curvature, effective dielectric constant and Return loss (S11), mutual coupling coefficient (S12), Transverse Magnetic TM 10 mode
... Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [13,14] as: (4) where 2b is a length of the patch antenna, a is a radius of the cylinder, 2θ is the angle bounded the width of the patch, ε represents electric permittivity and µ is the magnetic permeability as shown in Figure 4. [9] Joseph A. et al, presented an approach to the analysis of microstrip antennas on cylindrical surface. In this approach, the field in terms of surface current is calculated, while considering dielectric layer around the cylindrical body. ...
... Now, let the coaxial feed as a rectangular current source with equivalent cross-sectional area centered at , so, the current density will satisfy the Equation below: (14) Use of Equation (14) in (13) gives: (15) So, to get the input impedance, one can substitute in the following Equation: (16) where is the RF voltage at the feed point and defined as: ...
... Now, let the coaxial feed as a rectangular current source with equivalent cross-sectional area centered at , so, the current density will satisfy the Equation below: (14) Use of Equation (14) in (13) gives: (15) So, to get the input impedance, one can substitute in the following Equation: (16) where is the RF voltage at the feed point and defined as: ...
Article
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for return loss mutual coupling coefficient as a function of curvature for two element array antenna is introduced in this paper. These parameters are given for TM 10 mode and using three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass and Epsilam-10 ceramic-filled Teflon. Keywords Fringing field, Curvature, effective dielectric constant and Return loss (S11), mutual coupling coefficient (S12), Transverse Magnetic TM 10 mode.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Figurer 4: Geometry of cylindrical-rectangular patch antenna[9] Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
... So, the effective width for the equivalent capacitor s eff is given by Equation (13) as a function of area of the shaded area shown inFigure 6 and the thickness of that area. The effective filling factor is given by [10]: ...
Article
Full-text available
The fringing field has an important effect on the accurate theoretical modeling and performance analysis of microstrip patch antennas. Though, fringing fields effects on the performance of antenna and its resonant frequency have been presented before, effects of curvature on fringing field have not been reported before. The effective dielectric constant is calculated using a conformal mapping technique for a conformal substrate printed on a cylindrical body. Furthermore, the effect of effective dielectric constant on the resonance frequency of the conformal microstrip antenna is also studied. Experimental results are compared to the analytical results for RT/duroid-5880 PTFE substrate material. Three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass, and Epsilam-10 ceramic-filled Teflon are used for verifying the new model. KEYWORDS Fringing field, microstrip antenna, effective dielectric constant and Resonance frequency.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Figurer 4: Geometry of cylindrical-rectangular patch antenna[9] Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
... So, the effective width for the equivalent capacitor s eff is given by Equation (13) as a function of area of the shaded area shown inFigure 6 and the thickness of that area. The effective filling factor is given by [10]: ...
Article
Full-text available
The fringing field has an important effect on the accurate theoretical modeling and performance analysis of microstrip patch antennas. Though, fringing fields effects on the performance of antenna and its resonant frequency have been presented before, effects of curvature on fringing field have not been reported before. The effective dielectric constant is calculated using a conformal mapping technique for a conformal substrate printed on a cylindrical body. Furthermore, the effect of effective dielectric constant on the resonance frequency of the conformal microstrip antenna is also studied. Experimental results are compared to the analytical results for RT/duroid-5880 PTFE substrate material. Three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass, and Epsilam-10 ceramic-filled Teflon are used for verifying the new model. KEYWORDS Fringing field, microstrip antenna, effective dielectric constant and Resonance frequency.
... However, it is time consuming and sometimes cannot be used in reality because the distance between elements is too small. Some conformal arrays have been proposed to extend the scanning angle [12,13], but the application of conformal array is often subject to the conditions of application environments. In [14,15], the theory of unequally spaced array has been proposed, which has no grating lobes in the visible region when the distance between elements is greater than /2. ...
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A novel thinned array with symmetric distribution along the array center is proposed in this paper. The proposed symmetric thinned array is based on the theory of unequally spaced array and the amplitude of each element in the array can be changed by introducing the weighted function. The pattern of the proposed array can be properly adjusted by changing the weighted function and the amplitude of the weighted factor, which obviously releases new degrees of freedom in array design. It has advantages such as low side lobe level (SLL) in the visible region, no grating lobes, and low nearby side lobe level (NSL), which has good potential for wide-angle scanning. Both simulation and experiment have been done; the experiment results show that, by applying this novel symmetric thinned array with pattern reconfigurable quasi-Yagi antenna, the scanning range of the array is −70°~70° in H -plane with SLL almost −10 dB below the maximum of the main beam. The 3 dB beam-width coverage is −86°~86°, which means that the proposed array can realize the entire upper-space beam coverage and restrain the SLL at the same time.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Figurer 4: Geometry of cylindrical-rectangular patch antenna[9] Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
Conference Paper
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss, voltage standing wave ratio and electric and magnetic fields is introduced in this paper. These parameters are given for TM10 mode and TM01 mode Epsilam-10 ceramic-filled Teflon substrate material. Keywords: Fringing field, Curvature, effective dielectric constant and Return loss (S11), Voltage Standing Wave Ratio (VSWR), Transverse Magnetic TM01 and TM01 modes.
... Figurer 4: Geometry of cylindrical-rectangular patch antenna[9] Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
Article
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss, voltage standing wave ratio and electric and magnetic fields is introduced in this paper. These parameters are given for TM 01 mode and using two different substrate materials RT/duroid-5880 PTFE and K-6098 Teflon/Glass. Experimental results for RT/duroid-5880 PTFE substrate are also introduced to validate the new model. Keywords: Fringing field, Curvature, effective dielectric constant and Return loss (S11), Voltage Standing Wave Ratio (VSWR), Transverse Magnetic TM 01 mode.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
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Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective d ielectric constant and then all antenna parameters. A new mathematical model for inpu t impedance, return loss, voltage standing wave ratio and electric and magnetic fields is introduced in this paper. These parameters are given for TM 01 mode RT/duroid-5880 PTFE substrate material. The range of operation is around 4.7 GHz.
... Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9,10] ...
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Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss and voltage standing wave ratio is introduced in this paper. These parameters are given for TM 01 mode and using two dif-ferent substrate materials K-6098 Teflon/Glass and Epsilam-10 Ceramic-Filled Teflon materials.
... Les antennes utilisées étaient à la base des guides d'ondes ou des fentes de dimensions variable, qui permettent de réaliser des retards pour obtenir une onde plane [80]. La technologie microruban a permis de réduire les dimensions axiales de ce genre d'antenne par l'utilisation de patchs diélectriques sans plan de masse [83]. En effet, il est aussi possible de jouer sur la permitivité ε r ou la perméabilité µ r du matériau pour faire varier la phase par l'ajout des ferrites ou de matériaux ferroélectriques [84][85] [86]. ...
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The PhD work is carried out at the Laboratory of Electronics, Antennas and Telecommunications in the frame of a millimetre detection system in the used for two projects. The INFRADAR Project in collaboration with companies (ATE and Opéra Ergonomie) aims to conceive a flying assistance system for helicopters in order to avoid obstacle as high voltage power line and pylons at long range. The Sakura Project in collaboration with a foreign institute LEAT, (Electronic Navigation Research Institute of Tokyo) is focused on the Foreign Object and Debris detection (FOD) on airport runways. The first chapter is a state of art of millimetre radar and antennas. The chosen antenna for our application is a reflectarray. The second chapter is dedicated to the study of originals elementary cells that allow polarisation conversion and frequency stability. The chapter three describes the three developed reflectarrays with circular polarisation, simultaneous multi-beam operation and low noise radiation level. The chapter four talks about the several measurements campaigns carried out in Tokyo and Sendaï for the Sakura Project. The results will be compared to a theoretic model to define the system limitation. Finally, we discuss in the chapter 5 about the measurements carried out at Aix en Provence and Sophia Antipolis in the framework of the INFRADAR Project. This latter being just started the first results underline the detection capacities for our application.
... Furthermore, conformal arrays can afford larger beam coverage range besides planar arrays. Hence, the designs of conformal array antennas have been an attractive research field, and many significant investigations have been reported, such as the conformal waveguide slot arrays [1] and the conformal microstrip patch arrays [1][2][3][4][5][6][7][8][9][10][11]. As compared to conformal waveguide slot arrays, conformal microstrip patch arrays have the advantage of lighter weight, smaller size, and better integration with aircrafts. ...
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A Ku-band wideband conformal array antenna with 13 × 19 elements is presented in the paper. The array has a spherical structure, and its element is a proximity-coupled stacked patches antenna with a cavity-backed ground plane. The stacked patches and the cavity produce multiple coupled resonances, which enhance the bandwidth of the element extremely. A simulated model with the reasonable dimensions is framed with the coupling analyses, and the effective simulated results and good computing efficiency are obtained simultaneously. The measured results of the center embedded element in the whole array show a bandwidth exceeding 40% VSWR < 2 , which is close to the simulated matching performance.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [13, 14] as: ...
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Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for return loss and mutual cou-pling coefficient as a function of curvature for two element array antenna is introduced in this paper. These parameters are given for TM 01 mode and using three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass and Epsilam-10 ceramic-filled Teflon. Keywords Fringing field, Curvature, effective dielectric constant and Return loss (S11), mutual coupling coefficient (S12), Transverse Magnetic TM 01 mode.
... The radome does not need to install; even if the radome is installed, as the microstrip antenna and its close proximity, distortion of the antenna is greatly reduced [4]. 4. With planer arrays the radiation pattern changes with the direction of scan, while conformal arrays with rotational symmetry (cylindrical profile) can have scan-invariant pattern [5]. 5. Cylindrical conformal gives nearly Omnidirectional radiation pattern [6]. 6. ...
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In this paper, the comprehensive study of the conformal microstrip printed antenna is presented. The main advantages and drawbacks of a microstrip conformal antenna are introduced. The earlier researches in cylindrical-rectangular patch and conformal microstrip array are summarized. The effect of curvature on the conformal Microstrip antenna patch on conical and spherical surfaces is studied. Some new flexible antenna is given for different frequencies. Finally, simulation software is used to study the effect of the curvature on the input impedance, return loss, voltage standing wave ratio, and resonance frequency.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
Article
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss, voltage standing wave ratio and electric and magnetic fields is introduced in this paper. These parameters are given for TM 10 mode and using two different substrate materials RT/duroid-5880 PTFE and K-6098 Teflon/Glass. Experimental results for RT/duroid-5880 PTFE substrate are also introduced to validate the new model. Keywords Fringing field, Curvature, effective dielectric constant and Return loss (S11), Voltage Standing Wave Ratio (VSWR), Transverse Magnetic TM 10 mode.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Figurer 4: Geometry of cylindrical-rectangular patch antenna[9] Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
Article
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss, voltage standing wave ratio and electric and magnetic fields is introduced in this paper. These parameters are given for TM 01 mode RT/duroid-5880 PTFE substrate material. The range of operation is around 4.7 GHz.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
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Full-text available
Curvature has an important effect on fringing field of a microstrip antenna and consequently fringing field affects the effective dielectric constant and then all antenna parameters. A new mathematical model for resonance frequency, gain, efficiency and quality factor as a function of curvature is introduced in this paper. These parameters are given for TM 01 mode and using three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass and Epsilam-10 ceramic-filled Teflon.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
Article
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for resonance frequency, gain, efficiency and quality factor as a function of curvature is introduced in this paper. These parameters are given for TM 10 mode and using three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass and Epsilam-10 ceramic-filled Teflon.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Figurer 4: Geometry of cylindrical-rectangular patch antenna[9] Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
Article
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss, voltage standing wave ratio and electric and magnetic fields is introduced in this paper. These parameters are given for TM 10 mode and TM 01 mode Epsilam-10 ceramic-filled Teflon substrate material.
... The perception of typical modes will be helpful for attaining the rounded polarization [23]. The spherical polarization is necessary to combine two orthogonal and linearly polarized modes with the same current amplitude and in quadrature phase shift (90°). ...
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... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Figurer 4: Geometry of cylindrical-rectangular patch antenna[9] Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [9, 10] as: ...
Article
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss, voltage standing wave ratio and electric and magnetic fields is introduced in this paper. These parameters are given TM 10 mode and RT/duroid-5880 PTFE substrate material. The introduced model is valid at superhigh frequency range (3– 30 GHz). (VSWR), Transverse Magnetic TM 10 and TM 01 modes.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [13, 14] as: ...
Article
Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for return loss mutual coupling coefficient as a function of curvature for two element array antenna is introduced in this paper. These parameters are given for TM 01 mode and using three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass and Epsilam-10 ceramic-filled Teflon. Keywords Fringing field, Curvature, effective dielectric constant and Return loss (S11), mutual coupling coefficient (S12), Transverse Magnetic TM 01 mode.
... The manufacturing of this antenna is easy with respect to spherical and conical antennas. Effect of curvature of conformal antenna on resonant frequency been presented by Clifford M. Krowne [13, 14] as: ...
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Full-text available
Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for return loss mutual coupling coefficient as a function of curvature for two element array antenna is introduced in this paper. These parameters are given for TM 10 mode and using three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass and Epsilam-10 ceramic-filled Teflon. Keywords Fringing field, Curvature, effective dielectric constant and Return loss (S11), mutual coupling coefficient (S12), Transverse Magnetic TM 10 mode.
... So far, however, the CAenabled UAV mmWave network is almost untouched in the literature. Regarding the mmWave CA, there are only a few recent works on the radiation patterns and beam scanning characteristics [20] and the performance evaluation of CAbased beamforming for static mmWave cellular networks [21]. These works validate the potential advantage of CA in the static mmWave networks, which are not applicable to mobile UAV mmWave networks. ...
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Curvature has a great effect on fringing field of a microstrip antenna and consequently fringing field affects effective dielectric constant and then all antenna parameters. A new mathematical model for input impedance, return loss and voltage standing wave ratio is introduced in this paper. These parameters are given for TM 10 mode and using two dif-ferent substrate materials K-6098 Teflon/Glass and Epsilam-10 Ceramic-Filled Teflon materials. Keywords Fringing field, Curvature, effective dielectric constant and Return loss (S11), Voltage Standing Wave Ratio (VSWR), Transverse Magnetic TM 10 mode.
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This paper describes the design of a novel cylindrical millimeter-wave microstrip antenna (MA) with broad beamwidth by means of isotropic transformation (IT). A planar millimeter-wave antenna with broad beamwidth is designed first, and then IT is used to design a conformal one based on the planar structure. In addition, phased array with eight present elements has been designed as an example. Finally, numerical results are given to show that the present antenna possesses broad beamwidth and its array is of large scanning angle, which also verify the validity of the method of IT.
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Conformal arrays possess certain desirable characteristics for deployment on unmanned aerial vehicles and other payload-limited platforms: aerodynamic design, minimal payload weight, increased field of view without the need for cumbersome mechanical couplings and rotary joints, and ease of integration with diverse sensor functions. This paper examines the adaptive detection performance potential of aerospace moving target indication radar employing a conformal antenna array. We consider four candidate conformal designs taking the following shapes: belly-mounted canoe, airfoil, cone and chined radome. Furthermore, we compare results to side- and forward-looking planar arrays. We find that array nonlinearity and orientation induce clutter non-stationarity; this non-stationary behavior adversely affects space–time adaptive processing implementations necessary for effective clutter suppression. We find that additional adaptive losses exceed as a result of conformal geometry-induced clutter non-stationarity. Several mitigating solutions to non-stationarity are given.
Conference Paper
This paper extends a beam pattern synthesis technique to a conformal array geometry. An array of simple slot radiating elements is postulated to cover a surface typical of the nosecone of an aircraft or missile. The far field element patterns for both polarization components are derived and applied to an iterative synthesis algorithm based on maximizing directivity subject to specified sidelobe constraints. Synthesized patterns with specified sidelobe levels are presented. Null steering is demonstrated, and beamwidth and directivity performance is considered as a function of scan angle. Near hemispheric coverage is demonstrated by assuming a capability to switch elements around the cone periphery. These results indicate the potential utility of conformal arrays for airborne applications. By continuing demonstration of useful beam patterns, directivities, and wide scan angles, conformal arrays may routinely find their way onto airborne vehicles, where they can introduce the additional benefits of reduced aerodynamic drag, weight and space savings and reduction of radome signal distortion.
Conference Paper
In this paper we present a methodology on how to use directive elements in an adaptive array methodology. Typically one uses isotropic elements having practically no gain then the signal level is increased by putting hundreds and thousands of these elements together. In this paper we demonstrate a methodology where the elements can be arbitrarily spaced and may even be non-planar. In addition it is shown how to deal with nonuniformly spaced and non-planar arrays. We illustrate these principles in a direction of arrival (DOA) estimation utilizing directive elements.