Beam-scanning Antenna Research Articles

Dual‐layer frequency beam‐scanning antennas without specifically designed radiation elements by using tile‐configured power‐dividers

In this article, two dual-layer frequency beam-scanning antennas (FBSAs) without specifically designed radiation elements are proposed. For the realization of such FBSAs, two tile-configured stripline power-dividers with in-phase outputs are designed. These power-dividers enable conventional radiation elements such as the Yagi-Uda antenna to be usable in a FBSA with the dual-layer configuration, and therefore reduce the complexity of the overall array that is one major issue in our previous work. In the first design, the input of the array is constructed by a bilateral broadside-coupled suspended stripline (BBSS). Specific substrate thickness is required for the connection between an SMA and the BBSS and therefore, an improvement is conducted by using a proposed broadside-connected double-layer coplanar waveguide (BD-CPW) as the input. For both power-dividers, the insertion loss is smaller than 0.25 dB, together with a phase imbalance smaller than 1°. For validation, two 20-element FBSAs centered at 8.75 GHz with Yagi-Uda radiation elements are designed, fabricated, and also verified in the measurement.

A Low-Sidelobe Circularly Polarized Continuous Beam-Scanning Array Using Double-Layer Rotated Structure for Ku-Band Satellite Communications

In this letter, a low-sidelobe level (SLL) circularly polarized (CP) beam-scanning array antenna based on a double-layer rotated structure is proposed for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Ku</i> -band satellite communications. It is comprised of a 16 × 24 CP substrate integrated waveguide slot antenna array and a rotatable feeding network. Detailed design methodology and working mechanism of the proposed antenna array are presented and analyzed, in particular, the method of achieving low SLL in Blass matrix design. A prototype was fabricated and measured, and the measured results indicate that an AR < 1.5 dB and a max SLL suppression of 19.4 dB at 11.95 GHz can be achieved. Its superiorities of low profile, low SLL, high gain, and continuous beam-scanning ability make the proposed array antenna a promising candidate for satellite communications.

Design and Analysis of a Compact Frequency Beam-Scanning Antenna Based on Composite FHMSIW/SSPP Waveguide

In this letter, a novel compact frequency beam-scanning antenna (FBSA) using composite waveguide based on folded half-mode substrate integrated waveguide (FHMSIW) and spoof surface plasmon polaritons (SSPP) is proposed. The novel composite FHMSIW/SSPP waveguide with compact size and high field-confinement is initiated by embedding dual SSPP structures into the FHMSIW. Its transmission characteristic has flexible features from both the FHMSIW and SSPP. To excite the radiation mode from the composite slow-wave waveguide, a simple single-sided sinusoidal modulation method is designed and used. In this way, the common open stop-band problem around broadside is effectively eliminated, and the beam-scanning range of the antenna can be flexibly designed without changing the modulation structure. The presented scanning antenna owns a compact size and a simple feeding network. The experimental results indicate that the proposed FBSA can achieve continuous beam scanning from backward to forward in a wide scanning range of 60° within a bandwidth of 7.7–10.1 GHz. The stable unidirectional radiation patterns and appropriate gains are also realized in the entire operating frequency band.

Integrated Slotted Serpentine Waveguide to Enhance Radiation Properties and Efficiency

Slotted waveguides are often used when high-power and high-efficiency antennas must be designed and particularly for millimeter waves applications (automotive radar for example). But it is not easy to choose any distance between radiation slots because of the guided wavelength, to obtain a wide beam in E plane and so to cover a wide angular sector in beam scanning antennas. Moreover, the main beam depends of frequency because it is a progressive wave antenna. In this article, the authors propose an original solution based on a slotted serpentine waveguide with slots on the narrow wall of the waveguide allowing to obtain a very wide radiation pattern in E plane, and this antenna is manufactured, thanks a PCB (printed circuit board) process with empty waveguides to enhance the efficiency for the global structure. Simulations and measurements are given to validate the idea and the technological process in W band, and some different prototypes demonstrate that it could be possible to obtain a wide angular sector in a beam scanning antenna configuration.

Two-Degree-of-Freedom Control of Field Distribution on Nonreciprocal Metamaterial-Line Resonators and Its Applications to Polarization-Plane-Rotation and Beam- Scanning Leaky-Wave Antennas

Two-degree-of-freedom control of field distribution on the pseudotraveling wave resonator using nonreciprocal metamaterial lines is demonstrated for the first time. Dynamic control of current distribution on the resonator is given based on circuit theory. We employed a normally magnetized ferrite microstrip line-based composite right-/left-handed (CRLH) transmission line as a metamaterial with variable phase-shifting nonreciprocity. Numerical simulation results show that the phase gradient of the fields along the resonator is controlled by the applied dc magnetic field to the ferrite. By changing the reflection coefficients of two reflectors inserted at both ends of the CRLH line section, current distribution along series and shunt branches of the unit cell is continuously and drastically changed under the resonance. The variable field distribution was implemented to polarization-plane-rotation and beam-scanning leaky-wave antennas. The experimental demonstration verifies our basic concept and shows the performance of the prototype antenna with a beam scanning angle of 20° and a continuous rotation angle of polarization plane by ±70° at the fixed frequency.

A High-gain and Beam-scanning Variable Inclination Continuous Transverse Stub Array Antenna Based on Linear-gradient Stub at Ku Band

A High-gain and Beam-scanning Variable Inclination Continuous Transverse Stub Array Antenna Based on Linear-gradient Stub at Ku Band

Successive Convex Approximation with Adaptive Beam Scanning Antenna to Fore Fend Data Collision in WSN

Successive Convex Approximation with Adaptive Beam Scanning Antenna to Fore Fend Data Collision in WSN

A compact wide-angle frequency beam-scanning antenna using modulated composite waveguide based on half-mode substrate integrated waveguide and spoof surface plasmon polariton structure

In this paper, we present a novel frequency beam-scanning leaky-wave antenna (LWA) based on a composite half-mode substrate integrated waveguide/spoof surface plasmon polariton (HMSIW/SSPP) waveguide. The new composite HMSIW/SSPP waveguide is accomplished by embedding periodical symmetric subwavelength grooves on both copper surfaces of the HMSIW, which owns flexible transmission characteristics attributed to its features from both HMSIW and SSPP. The conversion of propagating slow-wave mode to radiation mode is devised by a double-sided symmetric sinusoidal modulation method with a π/2 displacement between the top- and bottom-surface. This double-sided modulation method not only offers a compact structure but also effectively eliminates the open stopband. A prototype of the proposed antenna is fabricated and measured to verify the predicted performance from simulation. Experimental results show that the proposed antenna achieves a continuous wide scanning range of 125° from backward to forward for lateral unidirectional radiation with an average peak gain level of 9.1 dBi from 6.3 to 9.7 GHz. And the compact antenna volume of 0.40 × 8.0 × 0.013 λ03 offers a well scanning rate (36.8°/GHz) and a very high gain value per unit volume (219 dBi/λ03).

Risley-Prism-Based Dual-Circularly Polarized 2-D Beam Scanning Antenna With Flat Scanning Gain

Although the two-dimensional (2-D) beam scanning antenna based on the Risley-prism (R-P) principle has been proposed, the previous research mainly used linear phase progression phase-shifting surfaces, which has the problem that the gain decreases rapidly when the beam scans to a large angle in the elevation plane. Here, exponential phase gradient phase-shifting surfaces based on the Risley-prism principle are innovatively proposed, which can realize the flat scanning gain of 2-D beam scanning antenna. In addition, a rotatable polarization control surface is introduced to make the proposed 2-D beam scanning antenna work in dual-circular polarization. The experimental results show that the maximum scanning angle of the antenna is 52° in the elevation plane and 360° in the azimuth plane. In particular, the gain variation of the beam is only 0.6 dB within elevation angle 45°, showing a flat scanning gain characteristic.

Novel Beam Scan Method of Fabry–Perot Cavity (FPC) Antennas

A new beam scanning method of a Fabry–Perot cavity (FPC) antenna is proposed. To obtain high gain in a target direction with a reduced sidelobe level (SLL), we devised a tapered partially reflective surface (PRS) as a superstrate. Moreover, to attain various beam scanning directions, a phase-controllable artificial magnetic conductor (AMC) ground plane with a broad reflection phase range and high reflection magnitudes was introduced. In the proposed method, a new formula to satisfy an FP resonance condition in a cavity for a scanned beam is also suggested. According to the formula, the FPC antenna can precisely scan the main beam in designed target directions with well-maintained high gain, which has been hardly achievable. In addition, our method demonstrates the potential of electrical beam-scanning antennas by employing active RF chips on the AMC cells. To validate the method, we fabricated a prototype FPC antenna for a scanned beam at θ = 30°. Furthermore, we conducted an additional simulation for a different beam scanning angle as well. Good agreement between the expected and experimental results verifies our design approach.

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

A unidirectional frequency beam‐scanning antenna using composite slow‐wave waveguide based on substrate integrated waveguide and spoof surface plasmon polariton structure

In this study, a novel frequency beam-scanning (FBS) antenna based on composite substrate integrated waveguide/spoof surface plasmon polariton (SIW/SSPP) waveguide is proposed. The composite SIW/SSPP slow-wave waveguide is designed by embedding a series of periodic subwavelength H-shaped grooves on the top surface of the SIW. Its transmission characteristics own both the features from SIW and SSPP, and can be flexibly mansplained by tuning the key structural parameters. To convert the propagating composite slow-wave mode into the radiation mode effectively, a new flexible digital modulation method with staggered metallic vias is proposed and used. The presented beam-scanning antenna has a simple feeding structure, a single dielectric layer, and a compact volume of 0.75 × 8.55 × 0.015 λ03. A prototype of the antenna is fabricated and tested to verify its performance. The experimental results demonstrate that the proposed antenna can realise a continuous beam-scanning angle of 49° in an operating bandwidth of 8.7–9.2 GHz with a high frequency-scanning sensitivity (FSS) of 9.8 °/100 MHz−1. Moreover, the measured results indicate that the antenna has high peak gain with an average level of 12.7 dBi, high radiation efficiency with an average level of 87%, and stable unidirectional radiation pattern in the working band.

A two‐dimensional beam scanning continuous transverse stub antenna based on a single‐layer compact linear source generator

To minimise the profile of Satcom-on-the-Move ground terminals, in this study, a two-dimensional beam-scanning continuous transverse stub antenna that is based on a compact linear source generator (LSG) is presented. A periodic anti-symmetric two-step (ASTS) structure cascaded with a broadband network is used to construct a single-layer compact LSG. The concept of a parallel-plate waveguide polarisation twister is used to design the ASTS unit that acts as a TE10-to-transverse electromagnetic wave converter, to which chamfers and T-type grooves are added to improve the output plane wave performance over the entire frequency band. A prototype array operating in the band 10.95–12.75 GHz is designed, fabricated, and measured, and the experimental results agree well with the simulated ones. A beam-scanning range of ±61° in elevation is achieved at the central frequency. Although only 29 of 36 slots (ϕ = 0°) contribute to the radiation, the antenna aperture efficiency is still over 60% due to the superior performance of the single-layer minimised LSG.

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Special Issue on Low-Cost Wide-Angle Beam-Scanning Antennas

Wideband and Low-Loss Beam-Scanning Circularly Polarized Antenna Based on Air-Filled SIW

In this letter, a wideband beam-scanning antenna with circular polarization (CP) characteristics is proposed. The antenna is designed based on an air-filled substrate-integrated waveguide (SIW), which is composed of three layers of printed circuit board. Since the medium is dug out, the transmission structure has low-loss characteristics. An array of slots is etched on the top layer as radiating elements. Due to the fast-wave characteristic of the air-filled SIW, the antenna can radiate over a wide bandwidth. The proposed antenna is designed, fabricated, and tested. Within the frequency band of 12-18 GHz (40% relative bandwidth), the measured scanning angle is from 28° to -13°. The antenna axial ratio is below 3 dB at the corresponding maximal beam direction, and the gain is above 10.30 dBic over the whole band. This antenna has potential applications in the satellite and wireless communication systems for its advantages of wideband, low loss, CP properties, low cost in fabrication, and simplicity in design.

A Novel Dual-Band Beam Scanning Antenna Based on slot Active Frequency-Selective Surfaces [Antenna Applications Corner

A novel dual-band electronically beam scanning antenna based on a slot active frequency-selective surface (SAFSS) is proposed in this article. Each unit cell used in an SAFSS screen has two slots with four variable capacitors utilized to achieve high tuning ranges and dual modes. To achieve an adequate single mode, specific capacitances are used in each slot to overlap the two resonances. These dual modes in each unit cell create specific conditions for an antenna to control beams in dual bands simultaneously. An antenna prototype operating at the 1.5- and 2.45-GHz frequency bands is fabricated and measured. The results show that the fabricated antenna can scan its main beam in the dual band across the entire azimuth plane with a 45d resolution. The designed dual-band antenna is inexpensive, has easy fabrication, and is capable of sweeping beams across the full 360? angular range in dual bands simultaneously.

A high‐gain circular polarization beam scanning transmit array antenna

A high-gain circular polarization (CP) beam scanning antenna based on planar transmit array (TA) is proposed. The planar TA is implemented using rectangular patches and square rings, and it has different frequency responses to two orthogonal polarized incident waves owing to different phase distributions in x- and y-direction. The TA can convert a linearly polarized spherical incident wave into a circularly polarized transmitted plane wave. In addition, beam scanning is achieved by in-plane translation of the feed antenna. The procedure is demonstrated for high-gain beam steering implementation operating in CP at the Ku-band. Full-wave simulation results demonstrate that the designed antenna enables elevation beam scanning from −33.6° to +33.6°, with a peak gain of 26.4 dBi. Scanning loss is better than 5 dB and the axis ratio remains below 3 dB for the entire scanning range in the frequency band of 13.9–14.9 GHz. Moreover, a prototype is fabricated and the measured results have good agreement with the simulated results, which confirms the feasibility of using this technology to achieve a high-gain, CP, low-cost and low cross-polarization beam scanning antenna.