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Showing papers in "IEEE Transactions on Antennas and Propagation in 1998"


Journal ArticleDOI
TL;DR: In this article, a simple formula is proposed to predict the frequency corresponding to the lower edge of the bandwidth for each of these configurations, including square, rectangular, and hexagonal disc monopole antennas.
Abstract: The circular disc monopole (CDM) antenna has been reported to yield wide-impedance bandwidth. Experiments have been carried out on a CDM that has twice the diameter of the reported disc with similar results. New configurations are proposed such as elliptical (with different ellipticity ratios), square, rectangular, and hexagonal disc monopole antennas. A simple formula is proposed to predict the frequency corresponding to the lower edge of the bandwidth for each of these configurations. The elliptical disc monopole (EDM) with ellipticity ratio of 1.1 yields the maximum bandwidth from 1.21 GHz to more than 13 GHz for voltage standing wave ratio (VSWR)<2.

866 citations


Journal ArticleDOI
TL;DR: In this article, the multiband behavior of the fractal Sierpinski (1915) antenna is described and compared to the well-known single-band bow-tie antenna.
Abstract: The multiband behavior of the fractal Sierpinski (1915) antenna is described. Due to its mainly triangular shape, the antenna is compared to the well-known single-band bow-tie antenna. Both experimental and numerical results show that the self-similarity properties of the fractal shape are translated into its electromagnetic behavior. A deeper physical insight on such a behavior is achieved by means of the computed current densities over the antenna surface, which also display some similarity properties through the bands.

754 citations


Journal ArticleDOI
TL;DR: In this article, a novel feed structure was proposed to excite a plane TEM wave in a parallel-plate waveguide, which is composed of densely arrayed posts on the same layer as the parallel plate.
Abstract: The authors propose a novel feed structure to excite a plane TEM wave in a parallel-plate waveguide. The feed waveguide is composed of densely arrayed posts on the same layer as the parallel plate. The posts can be easily fabricated at low cost by making metalized via holes in a grounded dielectric substrate. Such a procedure results in a quite simple fabrication of the antenna. The feed waveguide is designed to obtain a uniform division, which is confirmed by measurements on a 40-GHz band model.

568 citations


Journal ArticleDOI
TL;DR: In this article, a rotational element was used to achieve cophasal far-field radiation for a circularly polarized microstrip reflectarray with elements having variable rotation angles, which is the largest reflectarray ever developed using microstrip patches.
Abstract: This paper demonstrates a novel means of achieving cophasal far-field radiation for a circularly polarized microstrip reflectarray with elements having variable rotation angles. Two Ka-band half-meter microstrip reflectarrays have been fabricated and tested. Both are believed to be the electrically largest reflectarrays ever developed using microstrip patches. One, a conventional design, has identical square patches with variable-length microstrip phase-delay lines attached. The other has identical square patches with identical microstrip phase-delay lines but different element rotation angles. Both antennas demonstrated excellent performance with more than 55% aperture efficiencies, but the one with variable rotation angles resulted in better overall performance. A brief mathematical analysis is presented to validate this "rotational element" approach. With this approach, a means of scanning the main beam of the reflectarray over a wide angular region without any RF beamformer by using miniature or micromachined motors is viable.

554 citations


Journal ArticleDOI
TL;DR: In this paper, a variation of the aperture-coupled stacked patch microstrip antenna is presented, which greatly enhances its bandwidth, and the impedance behavior of this antenna is compared with that of other wideband radiators.
Abstract: A variation of the aperture-coupled stacked patch microstrip antenna is presented, which greatly enhances its bandwidth. Bandwidths of up to one octave have been achieved. The impedance behavior of this antenna is compared with that of other wide-band microstrip radiators. Matching techniques for the antenna are presented and their relative merits discussed. The effects of varying several key physical parameters of the antenna are investigated, lending some insight into its wide-band operation. Variations on the design such as incorporation of additional patches are also discussed.

515 citations


Journal ArticleDOI
TL;DR: In this article, it was shown that the electromagnetic field can be accurately represented over a substantially arbitrary surface by a finite number of samples, even when the observation domain is unbounded.
Abstract: It is shown that the electromagnetic (EM) field, radiated or scattered by bounded sources, can be accurately represented over a substantially arbitrary surface by a finite number of samples even when the observation domain is unbounded. The number of required samples is nonredundant and essentially coincident with the number of degrees of freedom of the field. This result relies on the extraction of a proper phase factor from the field expression and on the use of appropriate coordinates to parameterize the domain. It is demonstrated that the number of degrees of freedom is independent of the observation domain and depends only on the source geometry. The case of spheroidal sources and observation domains with rotational symmetry is analyzed in detail and the particular cases of spherical and planar sources are explicitly considered. For these geometries, precise and fast sampling algorithms of central type are presented, which allow an efficient recovery of EM fields from a nonredundant finite number of samples. Such algorithms are stable with respect to random errors affecting the data.

500 citations


Journal ArticleDOI
TL;DR: An accurate method of moments solution of the combined field integral equation (CFIE) using the multilevel fast multipole algorithm (MLFMA) for scattering by large, three-dimensional (3-D), arbitrarily shaped, homogeneous objects.
Abstract: We present an accurate method of moments (MoM) solution of the combined field integral equation (CFIE) using the multilevel fast multipole algorithm (MLFMA) for scattering by large, three-dimensional (3-D), arbitrarily shaped, homogeneous objects. We first investigate several different MoM formulations of the CFIE and propose a new formulation, which is both accurate and free of interior resonances. We then employ the MLFMA to significantly reduce the memory requirement and computational complexity of the MoM solution. Numerical results are presented to demonstrate the accuracy and capability of the proposed method. The method can be extended in a straightforward manner to scatterers composed of different homogeneous dielectric and conducting objects.

321 citations


Journal ArticleDOI
TL;DR: In this paper, a vertical plane launch (VPL) technique was proposed to estimate a full 3D site-specific ray trace to predict propagation effects in cities for frequencies in the 300 MHz-3 GHz band.
Abstract: A vertical-plane-launch (VPL) technique for approximating a full three dimensional (3-D) site-specific ray trace to predict propagation effects in cities for frequencies in the 300 MHz-3-GHz band is described and its predictions are compared with measurements for Rosslyn, VA. The VPL technique employs the standard shoot and bounce method in the horizontal plane while using a deterministic approach to find the vertical displacement of the unfolded ray paths. This approximation is valid since building walls are almost always vertical. The VPL method shows significant improvement compared with the slant-plane/vertical-plane (SP/VP) method for rooftop antennas. For a base station located at street level, the VPL method gives better predictions than the two-dimensional (2-D) method in locations where propagation over buildings is significant.

302 citations


Journal ArticleDOI
TL;DR: Techniques to enhance the bandwidth of these antennas are presented, and valuable insight to the optimum design, namely broad bandwidth, small size, and ease of manufacturing, is given.
Abstract: Electrically small microstrip patches incorporating shorting posts are thoroughly investigated. These antennas are suitable for mobile communications handsets where limited antenna size is a premium. Techniques to enhance the bandwidth of these antennas are presented and performance trends are established. From these trends, valuable insight to the optimum design, namely broad bandwidth, small size, and ease of manufacturing, is given.

298 citations


Journal ArticleDOI
TL;DR: In this article, the design of a compact PIFA suitable for operation at 900 MHz was described, and modifications to this design were provided to operate in dual-frequency bands at 300 and 1800 MHz.
Abstract: Planar inverted F antennas (PIFA) have been proposed as possible candidates for mobile telephone handsets. We describe the design of a compact PIFA suitable for operation at 900 MHz. In addition, we provide modifications to this design that allow it to operate in dual-frequency bands at 300 and 1800 MHz. Finite-difference time-domain (FDTD) and experimental results are provided.

289 citations


Journal ArticleDOI
TL;DR: In this article, a review of the extrapolation methods for accelerating the convergence of Sommerfeld-type integrals is presented, which arise in problems involving antennas or scatterers embedded in planar multilayered media.
Abstract: A review is presented of the extrapolation methods for accelerating the convergence of Sommerfeld-type integrals (i.e. semi-infinite range integrals with Bessel function kernels), which arise in problems involving antennas or scatterers embedded in planar multilayered media. Attention is limited to partition-extrapolation procedures in which the Sommerfeld integral is evaluated as a sum of a series of partial integrals over finite subintervals and is accelerated by an extrapolation method applied over the real-axis tail segment (/spl alpha/,/spl infin/) of the integration path, where /spl alpha/>0 is selected to ensure that the integrand is well behaved. An analytical form of the asymptotic truncation error (or the remainder), which characterizes the convergence properties of the sequence of partial sums and serves as a basis for some of the most efficient extrapolation methods, is derived. Several extrapolation algorithms deemed to be the most suitable for the Sommerfeld integrals are described and their performance is compared. It is demonstrated that the performance of these methods is strongly affected by the horizontal displacement of the source and field points /spl rho/ and by the choice of the subinterval break points. Furthermore, it is found that some well-known extrapolation techniques may fail for a number of values of /spl rho/ and ways to remedy this are suggested. Finally, the most effective extrapolation methods for accelerating Sommerfeld integral tails are recommended.

Journal ArticleDOI
TL;DR: In this article, the authors used selective lateral etching based on micromachining techniques to enhance the performance of rectangular microstrip patch antennas printed on high-index wafers such as silicon, GaAs, and InP.
Abstract: This paper presents the use of selective lateral etching based on micromachining techniques to enhance the performance of rectangular microstrip patch antennas printed on high-index wafers such as silicon, GaAs, and InP. Micromachined patch antennas on Si substrates have shown superior performance over conventional designs where the bandwidth and the efficiency have increased by as much as 64% and 28%, respectively. In this work, the silicon material is removed laterally underneath the patch antenna to produce a cavity that consists of a mixture of air and substrate with equal or unequal thicknesses. Characterization of the micromachined patch antenna is presented herein and includes a discussion on the bandwidth improvements, radiation patterns, and efficiency of the patch. In addition, antenna placement on the reduced index cavity with respect to the high-index substrate is described to achieve efficiency improvements over conventional patch antennas.

Journal ArticleDOI
TL;DR: In this paper, a variety of formulations for the hybrid finite-element and boundaryintegral (FE-BI) method for three-dimensional (3-D) electromagnetic scattering by inhomogeneous objects are studied.
Abstract: This paper studies, in detail, a variety of formulations for the hybrid finite-element and boundary-integral (FE-BI) method for three-dimensional (3-D) electromagnetic scattering by inhomogeneous objects. It is shown that the efficiency and accuracy of the FE-BI method depends highly on the formulation and discretization of the boundary-integral equation (BIE) used. A simple analysis of the matrix condition number identifies the efficiency of the different FE-BI formulations and an analysis of weighting functions shows that the traditional FE-BI formulations cannot produce accurate solutions. A new formulation is then proposed and numerical results show that the resulting solution has a good efficiency and accuracy and is completely immune to the problem of interior resonance. Finally, the multilevel fast multipole algorithm (MLFMA) is employed to significantly reduce the memory requirement and computational complexity of the proposed FE-BI method.

Journal ArticleDOI
TL;DR: In this paper, a ray-tracing method for wave propagation inside buildings is presented, where the cross sections of the ray tubes at the field points are evaluated to find the spreading factors of the waves and then the geometrical optics contributions at the locations of the receiving antenna.
Abstract: A ray-tracing method for waves inside buildings is presented. Ray tubes are used to model the wave propagation and penetration and all the significantly reflected and transmitted ray tubes from interfaces are included. Also, the cross sections of the ray tubes at the field points are evaluated to find the spreading factors of the waves and then the geometrical optics (GO) contributions at the locations of the receiving antenna. A program has been developed according to this ray-tracing technique that can be applied to simulate waves transmitted through and reflected from electrically large complex 2D and 3D bodies. To verify this ray-tracing program, 2D moment method (MM) solutions for wave propagating in a two-room structure and also through a stair-shaped wall above a lossy ground are used to compare with those obtained from the ray tracing. Besides, comparisons of field measurements and ray-tracing simulations at 900 and 1800 MHz performed in a corridor on different floors and inside a staircase are shown. The effective complex dielectric constants of the buildings determined from a free-space method are employed in the simulations and a vector network analyzer is used for the field measurements. Good agreements are obtained. In addition, measured results for waves penetrating an exterior wall with metal-framed windows at 1290 MHz are employed to test the ray-tracing solutions, which indicate that scattering from the metal frames may be significant for field points near the windows. This ray-tracing program can be applied to evaluate the channel characteristics for the indoor wireless communications.

Journal ArticleDOI
TL;DR: In this paper, an explicit finite-difference time-domain (FDTD) scheme for wave propagation in certain kinds of nonlinear media such as saturable absorbers and gain layers in lasers is proposed.
Abstract: An explicit finite-difference time-domain (FDTD) scheme for wave propagation in certain kinds of nonlinear media such as saturable absorbers and gain layers in lasers is proposed here. This scheme is an extension of the auxiliary differential equation FDTD approach and incorporates rate equations that govern the time-domain dynamics of the atomic populations in the medium. For small signal intensities and slowly varying pulses, this method gives the same results as frequency-domain methods using the linear susceptibility function. Population dynamics for large signal intensities and the transient response for rapidly varying pulses in two-level (absorber) and four-level (gain) atomic media are calculated to demonstrate the advantages of this approach.

Journal ArticleDOI
TL;DR: A new practical model is introduced, which provides a way to estimate body-shadowing effects deterministically with the existing ray-determination methods and is shown applying the procedure to a simple office layout.
Abstract: Deterministic propagation prediction methods proposed for indoor radio are useful for estimating the average propagation loss in real environments, which usually have complicated geometries. On the other hand, these methods generally fail to accommodate human body shadowing, which is a significant propagation effect in indoor picocells. Several empirical models to describe body shadowing have been reported. However, to our knowledge, no appropriate model that can be used in combination with deterministic propagation prediction methods has been provided in the literature. In this paper, a new practical model is introduced, which provides a way to estimate body-shadowing effects deterministically with the existing ray-determination methods. The detailed procedure to combine our body-shadowing model with the ray-determination methods is described. Several examples are shown applying the procedure to a simple office layout.

Journal ArticleDOI
TL;DR: In this paper, a novel finite-difference time-domain (FDTD) formulation for dispersive media called the JE convolution (JEC) method is derived using the convolution relationship between the current density J and the electric field E. The high accuracy of the JEC method is confirmed by computing the reflection and transmission coefficients for a nonmagnetized plasma slab in one dimension.
Abstract: A novel finite-difference time-domain (FDTD) formulation for dispersive media called the JE convolution (JEC) method is derived using the convolution relationship between the current density J and the electric field E. The high accuracy of the JEC method is confirmed by computing the reflection and transmission coefficients for a nonmagnetized plasma slab in one dimension. It is found that the new method has an accuracy comparable to the auxiliary differential equation (ADE) while having the same computational efficiency as the less accurate recursive convolution (RC) method. Numerical simulations also show that the JEC method exhibits significantly higher accuracy than the RC method in modeling wave attenuation inside the plasma.

Journal ArticleDOI
TL;DR: In this paper, the authors applied the method of moments (MoM) in conjunction with the asymptotic waveform evaluation (AWE) technique to obtain the radar cross section (RCS) of an arbitrarily shaped three-dimensional (3-D) perfect electric conductor (PEC) body over a frequency band.
Abstract: The method of moments (MoM) in conjunction with the asymptotic waveform evaluation (AWE) technique is applied to obtain the radar cross section (RCS) of an arbitrarily shaped three-dimensional (3-D) perfect electric conductor (PEC) body over a frequency band. The electric field integral equation (EFIE) is solved using the MoM to obtain the equivalent surface current on the PEC body. In the AWE technique, the equivalent surface current is expanded in a Taylor's series around a frequency in the desired frequency band. The Taylor series coefficients are then matched via the Pade approximation to a rational function. Using the rational function, the surface current is obtained at any frequency within the frequency range, which is in turn used to calculate the RCS of the 3-D PEC body. A rational function approximation is also obtained using the model-based parameter estimation (MBPE) method and compared with the Pade approximation. Numerical results for a square plate, a cube, and a sphere are presented over a frequency bandwidth. Good agreement between the AWE and the exact solution over the bandwidth is observed.

Journal ArticleDOI
TL;DR: A novel technique for electronically directing the radiation pattern of an antenna array employs a directional array with only one active element and three parasitic elements operating near resonance, lending the technology to applications in both terrestrial and satellite communications systems.
Abstract: Base-station tracking in mobile communications benefits from a directional antenna and so requires direction finding technology. A novel technique for electronically directing the radiation pattern of an antenna array employs a directional array with only one active element and three parasitic elements operating near resonance. Three different methods of direction finding are assessed; a coarse angular location method, a precise angular location method assuming one incident beam, and a precise angular location method with multiple incident beams. An array with n elements, if used in conjunction with a relatively simple controller, can be used to resolve n-1 signals. This technology can be implemented using both wire and patch antenna-array elements and either linear or circular polarization can be used, lending the technology to applications in both terrestrial and satellite communications systems.

Journal ArticleDOI
TL;DR: In this paper, a new inverse synthetic aperture radar (ISAR) algorithm is proposed for radar cross-section imaging and measurement from scattered fields, based on a spherical-wave near-field illumination of the target, overcomes the requirement for an expensive compact range facility to produce a plane wave illumination.
Abstract: The paper presents a new inverse synthetic aperture radar (ISAR) algorithm intended for radar cross-section (RCS) imaging and measurement from scattered fields. The method, based on a spherical-wave near-field illumination of the target, overcomes the requirement for an expensive compact range facility to produce a plane wave illumination. The formulation and the implementation of the algorithm are described. Some experimental results obtained in an anechoic chamber are presented to show RCS results similar to the conventional plane wave methods.

Journal ArticleDOI
TL;DR: An artificial neural network (ANN) has been developed and tested for square-patch antenna design that transforms the data containing the dielectric constant, thickness of the substrate, and antenna's dominant-mode resonant frequency to the patch length.
Abstract: An artificial neural network (ANN) has been developed and tested for square-patch antenna design. It transforms the data containing the dielectric constant (/spl epsiv//sub r/), thickness of the substrate (h), and antenna's dominant-mode resonant frequency (f/sub r/) to the patch length (l).

Journal ArticleDOI
TL;DR: In this article, a 3D transition connecting the patch to a perpendicular connector is presented, where the patch is suspended over the ground plane and supported by a nonconductive pin.
Abstract: The typical single-layer patch printed on a dielectric substrate is a narrow-band element. This well-known fact is mainly due to the limitations imposed by the dielectric substrate. From efficiency and cost considerations, in most of the cases, the substrate cannot be too thick. In order to increase the microstrip element bandwidth, additional resonators in different configurations and combinations can be used: parasitic elements, slots, etc. However, the microstrip antenna element with the widest bandwidth (a variation of the aperture-fed stacked-patch element) is about 40-50%. This antenna, an aperture-fed stacked patch, has a relatively poor front-to-back ratio, due to the fact that it has a slot in the ground plane. In this paper, a new type of patch element is presented. The patch is suspended over the ground plane and supported by a nonconductive pin. It is fed by a three-dimensional (3-D) transition connecting the patch to a perpendicular connector. The typical bandwidth of this element (in terms of VSWR) is 90%. When built on a large ground plane, the front-to-back of this element is better than 25 dB across the band.

Journal ArticleDOI
Abstract: For ptI seeibid vol46, no9, p1328, (1998)The uniform theory of diffraction (UTD) developed in part 1 is used to predict narrow- and wide-band propagation characteristics in tunnels at 900- and 1800-MHz Narrow-band propagation characteristics is shown in the spatial domain and wide-band propagation in the time domain In empty straight-tunnel environments, propagation exhibits a break-point phenomenon and has very short time delay spread In empty curved or branched tunnel environments, propagation suffers higher loss Vehicles cause additional propagation loss and larger varying time delay spread in tunnels The measured results have validated the accuracy of the theoretical model and provided important information on narrow-band and wide-band propagation characteristics in empty, branched and obstructed tunnels

Journal ArticleDOI
TL;DR: A fast full-wave analysis technique that can be used to analyze the scattering and radiation from large finite arrays of microstrip antennas is presented, demonstrating the accuracy, efficiency, and capability of this technique.
Abstract: A fast full-wave analysis technique that can be used to analyze the scattering and radiation from large finite arrays of microstrip antennas is presented. The technique discretizes the mixed potential integral equation (MPIE) in the spatial domain by means of a full-wave discrete complex image method. The del operators on the Green's functions are transferred from the singular kernel to the expansion and testing functions. The resultant system of equations is solved using the biconjugate gradient (BCG) method in which the matrix-vector product is evaluated efficiently using the fast Fourier transform (FFT). This results in an efficient and accurate computation of the scattering and radiation from finite arrays of microstrip antennas. Several numerical results are presented, demonstrating the accuracy, efficiency, and capability of this technique.

Journal ArticleDOI
TL;DR: In this paper, a theoretical model is proposed to compute the path loss in a vegetated residential environment, with particular application to mobile radio systems, where rows of houses or blocks of buildings are viewed as diffracting cylinders lying on the Earth and the canopy of the trees is located adjacent to and above the houses/building.
Abstract: A theoretical model is proposed to compute the path loss in a vegetated residential environment, with particular application to mobile radio systems. As in the past, rows of houses or blocks of buildings are viewed as diffracting cylinders lying on the Earth and the canopy of the trees is located adjacent to and above the houses/buildings. In this approach, a row of houses or buildings is represented by an absorbing screen and the adjacent canopy of trees by a partially absorbing phase screen. The phase-screen properties are found by finding the mean field in the canopy of the tree. Physical optics (PO) is then used to evaluate the diffracting field at the receiver level by using a multiple Kirchhoff-Huygens integration for each absorbing/phase half-screen combination.

Journal ArticleDOI
TL;DR: A meander element antenna was found to present some electrical and mechanical properties allowing convenient placement of tuning elements when configured as an electrically small transmitting antenna.
Abstract: For antennas to radiate at maximum efficiency, their dimensions must be on the same order as the radiated wavelength At frequencies below 30 MHz, antennas with efficient radiation are often too large for mobile and portable applications Smaller antennas can be made to radiate efficiently by use of matching networks For installation convenience and ease of adjustment, these networks are usually placed between the transmitter and the antenna input; but it has been found that for best radiation efficiency, matching network elements should be placed at points on the antenna structure Unfortunately, such matching networks must be tuned for each transmitting frequency and, when mounted on the antenna, they cannot easily be tuned A meander element antenna was found to present some electrical and mechanical properties allowing convenient placement of tuning elements when configured as an electrically small transmitting antenna Some simplified design guidelines were derived from experimental data

Journal ArticleDOI
TL;DR: In this article, the design criteria for antenna structures with improved radiation efficiency while operating in close vicinity to a biological scatterer are investigated using a simple /spl lambda//2 dipole combined with a directive or reflective element.
Abstract: In this paper the design criteria for antenna structures with improved radiation efficiency while operating in close vicinity to a biological scatterer are investigated. The study is performed using a simple /spl lambda//2 dipole combined with a directive or reflective element. The optimization criteria are the effective radiation efficiency, the spatial peak specific absorption rate (SAR), and the sensitivity of the input resistance to the distance from the scatterer. It is demonstrated that the primary design criterion to improve the radiation efficiency is not directivity but the reduction of the maximum incident magnetic field strength in the exposed skin area of the user's head. For the reflectively coupled dipole, all performance parameters are improved by several decibels compared to a standard, /spl lambda//2 dipole, whereas for some other directive structures, the performance is impaired. The study is conducted with the generalized multipole technique (GMT) numerical simulation method, the results of which are validated by measurement methods.

Journal ArticleDOI
TL;DR: In this paper, a new concept is presented, where the "printed circuit" is etched out of metal and supported at "strategic points" by (metallic or nonmetallic) posts.
Abstract: Printed microstrip antennas and arrays are known to have limitations in terms of bandwidth and efficiency, all imposed by the very presence of the dielectric substrate. Microstrip arrays printed on a very thin film and separated from the ground-plane by foam were successfully designed; however, the fabrication difficulties associated with the use of foam considerably increases the fabrication cost. In this paper, a new concept is presented. Rather than using a superstrata geometry, the "printed circuit" is etched out of metal and supported at "strategic points" by (metallic or nonmetallic) posts. The main motivation for this work was to obtain large microstrip arrays, which exhibit a higher efficiency than conventional ones, and can be fabricated using inexpensive large quantity production techniques. However, this technology was also used to develop many new types of microstrip antennas. Microstrip elements and arrays based on this technology were designed and fabricated for the L, S, and C bands.

Journal ArticleDOI
TL;DR: The Globalstar cellular-telephone satellite system is described, including its use of code-division multiple access (CDMA) as the basic modulation scheme.
Abstract: The Globalstar cellular-telephone satellite system is described, including its use of code-division multiple access (CDMA) as the basic modulation scheme. Use of diversity for signal quality as well as power control is described, Development of the complex array antennas for L-band (1.6 GHz) and S-band (2.5 GHz) communication with the hand-held radios is described in detail.

Journal ArticleDOI
TL;DR: In this article, a new and advanced sampling technique far-field interpolation with a nonredundant number of samples on plane-polar geometry has been experimentally validated for cases of both complex and only-amplitude measurements.
Abstract: A new and advanced sampling technique far-field interpolation with a nonredundant number of samples on plane-polar geometry has been experimentally validated for cases of both complex and only-amplitude measurements. Experimental results show good stability of the interpolation algorithm with respect to noise and the lack of samples in the case of a limited scanning area.