<![CDATA[ IEEE Transactions on Antennas and Propagation - new TOC ]]>
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TOC Alert for Publication# 8 2017August 21<![CDATA[Table of contents]]>658C13818230<![CDATA[IEEE Transactions on Antennas and Propagation]]>658C2C2506<![CDATA[Frequency-Agile Beam-Switchable Antenna]]>658381938262098<![CDATA[Investigations of a Load-Bearing Composite Electrically Small Egyptian Axe Dipole Antenna]]>658382738372822<![CDATA[Dual Null Steering and Limited Beam Peak Steering Using Triple-Mode Circular Microstrip Patch Antenna]]>11 mode, a TM_{21} mode shorted annular ring around it and another shorted annular ring supporting TM_{31} mode encompassing the other two radiators. Each mode is fed using two feed points to create right-handed circular polarization. Analytical and simulation studies show that by controlling the individual mode amplitude and phase ratios, radiation pattern can be reconfigured. Especially, two nulls can be generated in upper hemisphere and can be steered independently based on the ratio of applied excitation to each mode. This is a highly desirable feature for satellite receives antenna system with antijamming capability. To calculate the required modes excitation ratios, a MATLAB optimization code using a hybrid method of particle swarm optimization and pattern search was used. To apply the calculated excitation, an analog beamforming network consisting of digital variable gain attenuators, digital phase shifters, and low-noise amplifiers was used. This antenna was fabricated and tested for radiation patterns showing full hemispherical null steering along with limited beam peak steering.]]>658383838483339<![CDATA[Waveguide-Based Differentially Fed Dual-Polarized Magnetoelectric Dipole Antennas]]>$four$ probes and the latter by a turnstile junction orthomode transducer feed. Using 3-D printing technique, the corresponding prototypes are fabricated for demonstration. Experimental results show that the rectangular-shaped E-dipole design has a wide impedance bandwidth of 55.1% from 7.5 to 13.2 GHz and a stable gain of 6 ± 1.5 dBi. On the other hand, the triangular-shaped E-dipole design can achieve 62.8% impedance bandwidth from 7 to 13.4 GHz and 5.15 ± 0.95 dBi gain over the operating frequencies. Furthermore, it is found that both antennas have low cross polarization and backlobe radiation, both characteristics of ME dipoles. Due to the waveguide configuration, the proposed antennas have good mechanical and electrical performances. They can be easily implemented and applied for various high power capacity applications. With these advantages, the proposed antennas are good candidates for the satellite and other wireless communication systems.]]>658384938572657<![CDATA[On-Chip Dual-Band Rectangular Slot Antenna for Single-Chip Millimeter-Wave Identification Tag in Standard CMOS Technology]]>$2.5\times 2.5\times2.5$ mm^{3} with DRA.]]>658385838682131<![CDATA[Monopole Antenna Radiation Pattern Control via 3-D-Printed Dielectrics]]>658386938761740<![CDATA[A Wideband Circularly Polarized Omnidirectional Antenna Based on Excitation of Two Orthogonal Circular TE<sub>21</sub> Modes]]>21 mode over a wide bandwidth. It is shown that the circular TE_{21} mode generates a linearly polarized far-field electric field over the horizontal plane with its polarization tilt angle varying as a function of azimuth angle. It is also shown that the tilt angle varies by 90° for an azimuthal angle increase of 45°. To obtain circular polarization, two circular TE_{21} modes are excited such that one mode is spatially rotated by 45° with respect to the other mode. The phase difference between two modes is 90°. The modes are excited by an array of 16 monopole sectorial loop antennas to achieve a wide axial-ratio (AR) bandwidth. A right-handed CP antenna based on the proposed structure is fabricated and tested against simulation results. A feed network including Wilkinson power dividers and low-pass/high-pass phase shifters is also designed and fabricated to feed the antenna elements. The measurement results show 58% of 3-dB AR and 10-dB impedance bandwidth with the center frequency at 1.565 GHz. The total height of the antenna is 47 mm.]]>658387738882837<![CDATA[A Hybrid Slot/Monopole Antenna With Directional Heating Patterns for Microwave Ablation]]>$\pi $ - matching network. A prototype of this antenna, designed to operate at 7 GHz in egg white, was fabricated and used to perform ablation experiments at a power level of 20 W for 5 min. Experimental results agree well with simulations and confirm the capability of the antenna for generating directional heating patterns.]]>658388938962740<![CDATA[Lightweight Perforated Waveguide Structure Realized by 3-D Printing for RF Applications]]>658389739046245<![CDATA[A Twelve-Beam Steering Low-Profile Patch Antenna With Shorting Vias for Vehicular Applications]]>$\theta _{\mathrm {max}}= 30^{\circ }$ ). This beam is directed away from feeding patch corner. Therefore, the antenna can steer its tilted beam in four different space quadrants in front of the antenna by exciting one feed at a time. The antenna is also capable of generating eight other beams using multiple feed excitations. They are four additional titled beams (6.1 dBi, $\theta _{\mathrm {{max}}}= 30^{\circ }$ ), two tilted-twin beam (5.8 dBi, $\theta _{\mathrm {{max}}}= \pm 36^{\circ }$ ), one semi-doughnut beam (5.8 dBi), and one axial beam (8.2 dBi). The antenna is designed to operate at the test frequency of 2.4 GHz and has a height = 1.5 mm ($\lambda _{\mathrm {{0}}}$ /83). The impedance matching to $50~\Omega $ is achieved using right-angle slots etched on the patch antenna.]]>658390539122300<![CDATA[Printed Endfire Beam-Steerable Pixel Antenna]]>658391339237651<![CDATA[Advantageous Exploitation of Characteristic Modes Analysis for the Design of 3-D Null-Scanning Antennas]]>$J_{n})$ over the investigated platform, a null of the pattern can be placed in any desired direction in the upper hemisphere. A rectangular conductive plane has been taken into account as test case to validate the design strategy. Design guidelines are provided for selecting and placing the proper exciters in order to realize the suitable excitation of the current. Measurements on a realized prototype are in a good agreement with simulations, confirming the reliability of the proposed approach.]]>658392439343686<![CDATA[Back Radiation Suppression Through a Semitransparent Ground Plane for a Millimeter-Wave Patch Antenna]]>$0.8\lambda $ with uniform impedance distribution that can improve the front-to-back ratio of a wide-band patch antenna by 11.6 dB as compared to a similar sized metallic ground plane. The value of uniform impedance is obtained through analytical optimization by using asymptotic expressions in the Kirchhoff approximation of the radiation pattern of a toroidal wave scattered by a round semitransparent ground plane. The semitransparent ground plane has been realized using a low-cost carbon paste on a Kapton film. Experimental results match closely with those of simulations and validate the overall concept.]]>658393539411138<![CDATA[Vehicular Optically Transparent UHF Antenna for Terrestrial Communication]]>658394239497616<![CDATA[Pattern Synthesis of Unequally Spaced Linear Arrays Including Mutual Coupling Using Iterative FFT via Virtual Active Element Pattern Expansion]]>658395039582852<![CDATA[A Broadband High-Efficiency Reconfigurable Reflectarray Antenna Using Mechanically Rotational Elements]]>$15\times15$ manually rotated elements is first computed, simulated, and measured. Full-wave simulations show that the gain of the beam focused in ($\theta =20^{\circ }$ , $\varphi = 0^{\circ }$ ) direction is 25.8 dB and the 1-dB gain bandwidth is over 28.6%. The measured results show that the beam at ($\theta = 20^{\circ }$ , $\varphi = 0^{\circ }$ ) direction achieves the maximum gain of 25.6 dB, corresponding to an aperture efficiency of 51.8%. The beam-steering capability of the RRA is measured within ±60° angular range, and well-defined scanned beams are obtained with maximum scan loss of 3.7 dB. The versatile beam-forming capability of the RRA is also verified by synthesizing a square shaped beam and a cosecant shaped beam. Another micromotor-controlled prototype with 756 elements on an octagonal aperture is fabricated and its measured radiation performance validates the feasibility of the proposed design as well.]]>658395939662538<![CDATA[Revisiting Hybrid Interferometry With Low-Frequency Radio Astronomy Arrays]]>658396739752384<![CDATA[Effect of Wall-Surrounded Slot on Stepped Narrow Wall for Bandwidth Enhancement of Partially Parallel-Feeding Waveguide Traveling-Wave Array]]>658397639854615<![CDATA[Mutual Coupling Reduction Using Meta-Structures for Wideband, Dual-Polarized, and High-Density Patch Arrays]]>$\pi$ -shaped elements. By incorporating the meta-structures into the array configuration, the isolation levels between adjacent radiating elements in both the E- and H-planes orientations are improved by as much as 7.15 dB. The surface current distribution behaviors of the array with only the GCLLs and with only the $\pi$ -shaped elements are investigated thoroughly to explain the mutual coupling reduction mechanisms. A proof-of-concept array was constructed and tests were performed that validate the reported design principles and simulation results.]]>658398639982833<![CDATA[Slot-Coupled Circularly Polarized Array Antenna With Substrate-Integrated Waveguide Cavity for Parallel-Plate-Mode Suppression]]>$8 \times 8$ phased CP array system is experimentally validated, and shown to exhibit the expected improvements in terms of gain, cross-polarization level, and axial ratio. The obtained results clearly demonstrate the advantages of the proposed antenna for CP phased array systems.]]>658399940062706<![CDATA[A Three-Element Biomimetic Antenna Array With an Electrically Small Triangular Lattice]]>$0.05 \lambda _{0}$ , where $\lambda _{0}$ is the free-space wavelength. Using a triangular lattice allows for maximizing the phase sensitivity of the array over a 360° angular range. Moreover, it will allow for resolving ambiguities when such BMAAs are used in small-aperture direction finding systems. The three strongly coupled antennas are connected to an external coupling network with three inputs and three outputs. This network augments the mutual coupling between the strongly coupled antennas and is designed to maximize the output phase difference between each two antenna elements without sacrificing the output power level of the array compared with a conventional array occupying the same aperture. A modal analysis technique is also presented and used to design a prototype of the proposed array operating at 600 MHz. This prototype was fabricated and experimentally characterized. Measurement results are shown to be in very good agreement with theory.]]>658400740162468<![CDATA[Overlapped Phased Array Antenna for Avalanche Radar]]>658401740263643<![CDATA[Efficiency Improvement of Time Modulated Array With Reconfigurable Power Divider/Combiner]]>658402740373218<![CDATA[Wideband Excitations of Higher-Order Mode Substrate Integrated Waveguides and Their Applications to Antenna Array Design]]>40 mode. The excitation structures exhibit broad bandwidth and good mode purity. Moreover, they can be extended to realize transitions exciting TE_{60}, TE_{80}, $\ldots $ , TE$_{m\mathrm {0}}[m = 6, 8,\ldots 2 \times (n + 3$ ), n is a natural number] modes. As application examples, a $4 \times 4$ -element slot array is designed. Measured results demonstrate that the slot array inherits the merits of the excitation and shows a simple structure, broadside radiation, high aperture efficiency, and good radiation efficiency.]]>658403840474611<![CDATA[Conical Conformal Shaped-Beam Substrate-Integrated Waveguide Slot Array Antenna With Conical-to-Cylindrical Transition]]>658404840562974<![CDATA[Compact Single- and Dual-Band Filtering Patch Antenna Arrays Using Novel Feeding Scheme]]>658405740663185<![CDATA[Low-Sidelobe Air-Filled Slot Array Fabricated Using Silicon Micromachining Technology for Millimeter-Wave Application]]>658406740743006<![CDATA[Pattern Synthesis With Multipoint Accurate Array Response Control]]>$ {\textrm {A}}^{2}\textrm {RC} $ ) algorithm are presented. It is shown that the array weight vector obtained by the $ {\textrm {A}}^{2}\textrm {RC} $ algorithm to control the normalized response at a single direction in each step belongs to a specific set. Thus, an appropriate weight vector chosen from the intersection of weight vector sets corresponding to the desired responses at multiple directions is capable of simultaneously controlling those responses. This results in the so-called multipoint accurate array response control ($ {\textrm {MA}}^{2}\textrm {RC} $ ) algorithm. Moreover, in order to avoid possible beam axis shift in pattern synthesis, a modified $ {\textrm {MA}}^{2}\textrm {RC} $ ($ {\textrm {M}}^{2}{\textrm {A}}^{2}\textrm {RC} $ ) algorithm is proposed by imposing a derivative constraint on the direction of beam axis. Representative numerical examples are provided to demonstrate the effectiveness of the proposed $ {\textrm {MA}}^{2}\textrm {RC} $ and $ {\textrm {M}}^{2}{\textrm {A}}^{2}\textrm {RC} $ algorithms for multipoint responses control and pattern synthesis.]]>658407540882979<![CDATA[Design and Analysis of a Multilayer Meander Line Circular Polarization Selective Structure]]>u-band 12–18 GHz. The functionality of the structure has been verified experimentally through measurements, both in reflection and transmission, with a total bandwidth of 42.0%, covering 86.7% of the K_{u} band. The simulated performance at oblique angles of incidence shows significant improvements when compared to classical resonant CPSSs.]]>658408941014235<![CDATA[Anisotropic Metamaterial as an Antireflection Layer at Extreme Angles]]>658410241143991<![CDATA[Minimization of Antenna Quality Factor]]>$Q$ as an alternative, so-called dual, problem. Taking advantage of modal decomposition and group theory, it is shown that the dual problem can easily be solved and always results in minimal quality factor $Q$ . Moreover, the optimization procedure is generalized to minimize quality factor $Q$ for embedded antennas, with respect to the arbitrarily weighted radiation patterns, or with prescribed magnitude of the electric and magnetic near fields. The obtained numerical results are compatible with previous results based on the composition of modal currents, convex optimization, and quasi-static approximations; however, using the methodology in this paper, the class of solvable problems is significantly extended.]]>658411541233440<![CDATA[Broadband and Thin Linear-to-Circular Polarizers Based on Self-Complementary Zigzag Metasurfaces]]>self-complementary indicates that the structure is identical to its complement, except for some translation smaller than the periodicity. This property together with the nonresonant response of the unit cells ensures broadband conversion from linear polarization to circular polarization. Although we have experimentally achieved a relative 3-dB-axial-ratio (AR) bandwidth (BW) of 53%, in principle, it could reach up to 70.5%. Moreover, the studied metasurface has a very small periodicity, which avoids any higher order grating lobes and provides angular stability of the phenomenon. In fact, the relative 3-dB-AR BW obtained in experiments stays always above 40% for incidence angles within ±30°. An excellent agreement was achieved among theory, simulations, and experiments.]]>658412441333328<![CDATA[Validating the Characteristic Modes Solvers]]>6584134414512648<![CDATA[A Spectral Integral Method for Smooth Multilayered Bodies of Revolution]]>658414641541794<![CDATA[Nonconformal Discretization of Electric Current Volume Integral Equation With Higher Order Hierarchical Vector Basis Functions]]>658415541693307<![CDATA[Stochastic Solutions to Rough Surface Scattering Using the Finite Element Method]]>658417041801013<![CDATA[An Integral Equation Modeling of Lossy Conductors With the Enhanced Augmented Electric Field Integral Equation]]>658418141902707<![CDATA[Improvement in Computation Time of 3-D Scattering Center Extraction Using the Shooting and Bouncing Ray Technique]]>658419141992350<![CDATA[Dust Storm Attenuation Modeling Based on Measurements in Sudan]]>658420042082398<![CDATA[Improved Antenna Efficiency Measurement Uncertainty in a Reverberation Chamber at Millimeter-Wave Frequencies]]>$K$ -factor, number of uncorrelated paddle orientations, and coherence bandwidth. We calculated the uncertainty using the NIST microwave uncertainty framework capable of performing parallel sensitivity and Monte Carlo analyses. The framework enables us to capture and propagate the uncertainties in the S-parameter measurements to the final efficiency result. The expanded uncertainty that we achieved for these antenna efficiency measurements is 2.60%.]]>658420942194027<![CDATA[A Self-Structuring Impedance Matcher for In-Vehicle Digital Audio Broadcasting Applications]]>658422042292049<![CDATA[A Propagating Plane-Wave-Based Near-Field Transmission Equation for Antenna Gain Determination from Irregular Measurement Samples]]>658423042382753<![CDATA[Experimental Characterization of Circular Polarization Selective Structures Using Linearly Single-Polarized Antennas]]>658423942494756<![CDATA[Shielding Effectiveness of Modern Energy-Saving Glasses and Windows]]>658425042583467<![CDATA[A Dual-Polarized Dual-Band Antenna With Omni-Directional Radiation Patterns]]>01 mode, eight shorted metal pins, and open slots can radiate $\theta$ - and $\varphi$ -components, respectively. Omni-directional circular polarization can be generated over the lower band. When the basic TM_{02} mode is excited, omni-directional linear polarization can be generated over the higher band. Omni-directional circularly polarized fields and omni-directional linearly polarized fields can be achieved at both resonant frequencies. The circular patch antenna is printed on a substrate with a radius of 48 mm ($0.24~\lambda _{\mathrm {\mathbf {0}}}$ , where $\lambda _{\mathrm {\mathbf {0}}}$ is the wavelength in free space). The antenna has a low profile of 4 mm ($0.02~\lambda _{\mathrm {\mathbf {0}}}$ ). The antenna is fabricated and measured; the measured results show that the impedance bandwidths for VSWR <2 are 18 MHz (1566—1584 MHz) and 32 MHz (2440—2472 MHz). The axial ratio in the xoy plane is less than 3 dB over the lower band. These measured results are congruent with the simulated data. The antenna can be a good candidate for both GPS and WLAN applications. Besides, the S-parameters, radiation patterns, and some key structures are studied.]]>658425942621370<![CDATA[High-Efficient Circularly Polarized Magnetoelectric Dipole Antenna for 5G Applications Using Dual-Polarized Split-Ring Resonator Lens]]>$3\times4$ MNZ unit cell. The measured results indicate that the magnitude of $S_{11}$ is below −10 dB in the frequency range of 29.5–37 GHz. The resulting 3-dB axial ratio is over a frequency range of 32.5–35 GHz. The measured realized gain of the antenna is more than 10 dBi over a frequency band of 31–35 GHz achieving a radiation efficiency of 94% at 34 GHz.]]>658426342671507<![CDATA[A Wideband CP Crossed Slot Antenna Using 1- $\lambda $ Resonant Mode With Single Feeding]]>$\lambda $ resonant mode of slot radiator with single feeding for bandwidth enhancement. The impedance of a simple slot radiator is studied using computer simulation. Since operating the slot radiator in the 1-$\lambda $ resonant mode requires a longer slot length, a large square slot is used at both ends of the slot to reduce the required slot length. The results of the study are subsequently used to design a wideband circularly polarized (CP) crossed slot antenna (CSA) with single feeding. The CSA consists of two slot radiators having the same length and placed in a crossed shape, i.e., orthogonal positions. A single microstrip line with a via at the end is used to feed the CSA. By loading reactive elements with appropriate values on each slot near to the feed line, the two slots generate two linearly polarized electric fields with 90°-phase difference for CP operation. The CSA is studied and designed using simulation and measurement. Measured results show that the CSA has a wide impedance bandwidth of 1.52–3.44 GHz (1.92 GHz, 77.4%) and axial-ratio bandwidth of 1.73–3.01 GHz (1.28 GHz, 54%), much wider than the previous directional and bidirectional CSAs using single feeding.]]>658426842731635<![CDATA[Wideband CPW-Fed Flexible Bow-Tie Slot Antenna for WLAN/WiMax Systems]]>658427442771547<![CDATA[Single Open-Slot Antenna for LTE/WWAN Smartphone Application]]>$\Omega$ vertical feedline with two horizontally protruded feeding structures. To further attain good impedance matching for these two operating bands, an L-shaped metallic plate is used. From the measured results, good antenna efficiencies of more than 40% are demonstrated across the LTE/WWAN operation in the 698–960 MHz and 1710–2690 MHz bands.]]>658427842821649<![CDATA[Single-Feed Dual-Band Circularly Polarized Dielectric Resonator Antenna for CNSS Applications]]>111 and TE_{113}, and a cross slot is introduced to simultaneously achieve dual-band right-hand circular polarization. The measured −10 dB impedance bandwidths of 11.4% and 8.4%, 3-dB axial ratio (AR) bandwidths of 2.1% and 2.2%, and antenna gains of over 5.4 and 4.3 dBic are obtained for CNSS B3 and B1 bands, respectively. Reasonable consistency is achieved between measured and simulated results of reflection coefficients, ARs, and radiation patterns.]]>658428342872409<![CDATA[A Circularly Polarized High-Gain Antenna With Low RCS Over a Wideband Using Chessboard Polarization Conversion Metasurfaces]]>$X$ -band, excited by a sequentially rotated feeding network, is fabricated and measured. Simulated and measured results show that the left-hand CP gain of the antenna with CPCM is at least 3 dB higher than that of the reference antenna from 8.5 to 9.5 GHz and the monostatic RCS is effectively reduced from 6 to 14 GHz.]]>658428842922369<![CDATA[A mm-Wave Patch Antenna with Broad Bandwidth and a Wide Angular Range]]>658429342982543<![CDATA[A Multi-linear Polarization Reconfigurable Unidirectional Patch Antenna]]>11 mode with LP. By controlling the connections between the four shorting posts and the ground plane using p-i-n diodes, four reconfigurable polarization states at $\phi =0 {^{\circ }}$ , $\phi =45 {^{\circ }}$ , $\phi =90 {^{\circ }}$ , or $\phi =135 {^{\circ }}$ can be realized. The size of this antenna is about $0.57\lambda \times 0.57\lambda \times 0.07\lambda $ at 2.45 GHz. It can be easily fabricated and has a simple biasing network. The measured overlapping impedance bandwidth for different polarizations under the condition $|\text{S}11| \leq -10$ dB is from 2.33 to 2.50 GHz, which agrees well with the simulated one. Moreover, the antenna maintains stable radiation patterns and the measured realized gains range from 5.3 to 5.9 dBi.]]>658429943042062<![CDATA[Compact Laterally Radiating Dielectric Resonator Antenna With Small Ground Plane]]>111 mode of the DRA, which is an equivalent magnetic dipole. By combining this equivalent magnetic dipole and the electric dipole of the probe, a lateral radiation pattern can be obtained. This complementary antenna has the same E- and H-Planes patterns with low back radiation. Moreover, the cardioid-shaped pattern can be easily steered in the horizontal plane by changing the angular position of the patch (ground). To verify the idea, a prototype operating in 3.5-GHz long term evolution band (3.4–3.6 GHz) was fabricated and measured, with reasonable agreement between the measured and simulated results obtained. It is found that the measured 15-dB front-to-back-ratio bandwidth is 10.9%.]]>658430543101868<![CDATA[Dielectric Image Line-Based Leaky-Wave Antenna for Wide Range of Beam Scanning Through Broadside]]>$V$ -band. A prototype is fabricated and measured in Ku-band, which fairly agrees with simulated results.]]>658431143151823<![CDATA[Double-Reflector Configuration for Optimal Exposure of Wideband Focal-Plane Arrays With Optical Beamforming]]>658431643212935<![CDATA[Circularly Polarized Elliptical Microstrip Patch Reflectarray]]>$11\times11$ full-fledged reflectarray has been designed and fabricated. The reflectarray is fed by a linearly polarized horn. Measurement shows that the proposed CP elliptical microstrip patch reflectarray is able to achieve an antenna gain of 20.38 dBic and a 1-dB gain bandwidth of 11.6%. It also has a broad 3-dB axial ratio bandwidth of 12.47%.]]>658432243271582<![CDATA[94-GHz Compact 2-D Multibeam LTCC Antenna Based on Multifolded SIW Beam-Forming Network]]>$2 \times 4$ SIW slot antenna array, the multibeam antenna can realize eight symmetric scanning beams on 2-D with stable gains for a wide coverage. For demonstration, the two single-port antennas with different pitch-angle beams are fabricated and measured, and good agreements with the expectations are observed. The differences of the beam orientations are less than 5°, while the measured peak gains of the beams are about 8.5 dBi.]]>658432843332660<![CDATA[On Multimode Equivalent Network Representation of Finite Arrays of Open-Ended Waveguides]]>658433443391748<![CDATA[Synthesis of Subarrayed Monopluse Arrays With Contiguous Elements Using a DE Algorithm]]>658434043451798<![CDATA[Frequency-Selective Feeding Network Based on Directional Filter for Constant-Beamwidth Scalable Antenna Arrays]]>658434643501589<![CDATA[An Ultra-Wideband Horizontally Polarized Omnidirectional Circular Connected Vivaldi Antenna Array]]>$\vert S_{11}\vert <-10$ dB. Meanwhile, uniform omnidirectional radiation patterns with a gain variation of less than 1.5 dB have been obtained within the frequency band of 1.25–7.6 GHz (142.73%).]]>658435143562648<![CDATA[Bandwidth Study of the Stacked Mushroom EBG Unit Cells]]>658435743621923<![CDATA[3-D Frequency-Selective Rasorber With Wide Upper Absorption Band]]>658436343671092<![CDATA[Realization of Focused Beam and Shaped Beam Transmitarrays Based on Broadband Unit Cells]]>$K$ -band have been designed, fabricated, and measured. Four-layer unit cells allowing a transmission phase range of 360° are used. The gain of the beam-focusing TA is 30.3 dB at 19 GHz with an aperture efficiency of 34.9%. Compared with TAs proposed in the literature, the presented antenna bandwidth is almost two times larger with a −1 dB gain bandwidth of 18% and a −3 dB gain bandwidth of 25.5%. A second TA radiating a shaped beam was designed, and its measured pattern correlates well with theoretical calculations. The sensitivity of the proposed unit cells to fabrication errors and the effect of oblique incidence are also studied.]]>658436843731848<![CDATA[An Efficient High-Order Marching-on-in-Degree Solver for Conducting and Dielectric Bodies of Revolution]]>658437443781133<![CDATA[FMM-Accelerated Source-Model Technique for Many-Scatterer Problems]]>658437943841043<![CDATA[Spherical Wave Expansion With Arbitrary Origin for Near-Field Antenna Measurements]]>658438543881106<![CDATA[Surface Field Measurements From a Buried UHF Transmitter: Theory, Modeling and Experimental Results]]>−4 S/m). A strong interference pattern with nulls greater than −20 dB were observed extending laterally to more than 5 m. This interference was evident when both the transmitter and receiver lay on the surface and when separated by an above ground conducting shield. Forward modeling using the impedance method and the finite integral technique adequately predict the interference pattern. These observations impact open-pit mining, surface and buried wireless sensor networks, and under-road communications systems.]]>658438943931248<![CDATA[Introducing IEEE Collabratec]]>658439443942182<![CDATA[Fuel Your Imagination]]>658439543951693<![CDATA[Member Get-A-Member (MGM) Program]]>658439643963487<![CDATA[IEEE Transactions on Antennas and Propagation]]>658C3C3501<![CDATA[Institutional Listings]]>658C4C4437