Fabry-Perot Resonator Antenna Research Articles

Mechanical azimuthal beam‐steering Fabry–Perot resonator antenna with large deflection angle

AbstractContinuous beam steering approach with minimal power consumption is highly desirable in modern antenna designs. A simple mechanical method for achieving beam steering in the Fabry–Perot resonator antenna (FPRA) is presented. It involves rotating the upper phase gradient metasurface (PGM) mechanically to change the aperture phase distribution, so the beam is continuously steered in the azimuthal plane while maintaining a large elevation angle. The proposed PGM unit cell comprises a hexagonal ring and patch printed on both sides of the substrate, along with a honeycomb lattice. A prototype antenna operating at 5.65 GHz is fabricated and measured to validate the feasibility. Measurement results show that the FPRA achieves a gain of 14.9 dBi, and can continuously steer its beam in the azimuthal plane with an elevation angle of around θ = 50°. Measured radiation patterns in eight azimuthal directions (φ = 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°) are consistent with the simulated results. Compared with other electrical tuning methods, our design has a compact size and requires lower power for the PGM rotation.

Wideband RCS Reduction of Fabry-Perot Resonator Antenna Based on Diffuse Scattering Method

Wideband RCS Reduction of Fabry-Perot Resonator Antenna Based on Diffuse Scattering Method

A High-gain Fabry-Perot Resonator Antenna With Dual-sense Circular Polarization Diversity

A High-gain Fabry-Perot Resonator Antenna With Dual-sense Circular Polarization Diversity

A dual-band low-profile Fabry–Perot resonator antenna with single partially reflecting surface

ABSTRACTThis paper presents a novel design for a low-profile Fabry–Perot resonator antenna (FPRA) that operates at two distinct frequency bands using a single partially reflecting surface (PRS). The PRS is composed of two different types of unit cells arranged in a staggered fashion. These unit cells are comprised of double-sided complementary structures, including a square patch with a square aperture and a circular ring with a circular ring slot. To reduce the overall profile of the antenna, an artificial magnetic conductor (AMC) surface is utilized as the reflection plane. The proposed design employs a dual-band slotted patch antenna as the primary source. The overall dimensions of the FPRA are 91 mm×91 mm×5.54 mm. The performance of the prototype antenna is validated through measurement, demonstrating peak gains of 14.1 and 16.1 dBi at frequencies of 6.65 and 12.05 GHz, respectively. Additionally, the antenna exhibits −10 dB impedance bandwidths of 6.5–6.8 GHz and 12.15–12.23 GHz at the two frequency bands.

Gain enhancement of circularly polarized Fabry-Perot resonator antenna using simple superstrate

This communication presents a method to enhance the gain of a circularly polarized (CP) Fabry-Perot resonator antenna (FPRA) by using a simple superstrate. The proposed superstrate is a polarization conversion metasurface (PCM) which is capable of partial reflection and CP transmission phase manipulation. The partial reflection property of PCM is used to form FPRA with a feed, and the linear to circular polarization conversion capacity make the antenna realize CP radiation. Furthermore, the PCM can also correct the aperture field phase distribution of the antenna through tuning the CP transmission phase of each unit. Then the gain of the CP FPRA can be further improved. Finally, the CP radiation and gain enhancement of the FPRA are achieved by a simple superstrate without the need to add additional antenna structure. This makes the proposed antenna keep a simple structure. The performance of the antenna is verified by comparing the test results of the fabricated antenna with the simulation results. Measured results show that the antenna can realize well CP radiation at 10 GHz. After phase correction, the measured peak gain of the antenna is increased by 1 dB, reaches 18.2 dBic. The method proposed in this communication provides a new idea for improving the gain of CP FPRA while maintaining simple antenna structure.

Design of a wideband Fabry–Perot resonator antenna with a double‐layer partially reflective surface

A novel Fabry–Perot resonator antenna using a double-layer partially reflective surface (PRS) to enhance the operating bandwidth is proposed. Two layers of double-sided printed substrate are employed as the PRSs. A higher-permittivity dielectric substrate is inserted between the two PRSs to produce a positive reflection phase gradient, which is essential to expand the bandwidth. A wideband aperture-coupled microstrip antenna is utilized as the feed antenna to further improve the working bandwidth. A prototype of the proposed antenna is fabricated and tested to validate the simulated results. The experimental results show that the designed antenna has a wide impedance bandwidth ( S 11 < − 10 dB $$ \left|{S}_{11}\right|<-10\ \mathrm{dB} $$ ) of 9.43–13.0 GHz (35.7%) with a 3-dB gain bandwidth ranging from 9.12 to 12.26 GHz (31.4%) and a peak gain of 15.4 dBi at 10 GHz.

High-Gain Wideband Circularly Polarised Fabry-Perot Resonator Array Antenna Using a Single-Layered Pixelated PRS for Millimetre-Wave Applications.

In this paper, a wideband and high-gain circular polarised Fabry–Perot Resonator Antenna (FPRA) with a single partially reflective surface (PRS) layer is automatically generated and optimised using a VBA-based interface system between CST Microwave studio and Matlab. The proposed PRS layer is a promising superstrate for wideband and high-gain FP resonator antennas due to its relatively high reflection coefficient magnitude and positive phase gradient, which resemble that of the optimum PRS over the relevant frequency band. The circular polarisation was achieved using a sequential feeding network for a 2 × 2 array air-gapped slot-coupled elliptical patch antenna. The proposed design achieved an impedance bandwidth of 48.58% (15.3 GHz) ranging from 23.84 GHz to 39.14 GHz, and the −3 dB gain bandwidth was 22.42% (6.25 GHz) from 24.75 to 31 GHz, with a peak gain of 17.12 dB at 29 GHz, and an axial ratio bandwidth of 21.75% (6.2 GHz). In addition, the achieved radiation efficiency was 90%. Consistent and almost invariant radiation patterns are achieved over the millimetre-wave frequency band of interest. The experimental and simulated results are in good agreement, justifying the feasibility of the proposed design as a high-gain and wideband FP resonator array antenna for Mm-wave applications.

High gain and wide band fabry perot resonator antenna

High gain and wide band fabry perot resonator antenna

Multifunctional Low-Profile Fabry–Perot Resonator Antenna Integrated With Solar Cells

A novel multifunctional low-profile Fabry–Perot resonator (FPR) antenna integrated with solar cells (SCs) is proposed in this communication. It is mainly composed of a transparent partially reflective surface (PRS), a patch radiator, and an artificial magnetic conductor (AMC) made of SCs array. On the upper layer, the PRS is made of the transparent copper microgrid to perform the function of partial reflection as well as ensure that sufficient solar energy can be captured by the SCs. Here, the SCs array acting as AMC can reduce the profile of the FPR antenna, on the other hand, it can collect solar energy and convert it into direct current (dc) power to provide energy supply of the device. Through this design, the SCs and FPR antenna are well combined compatibly together. The proposed antenna is fabricated and verified, the measured results demonstrate that the proposed multifunctional FPR antenna has a realized gain of 11.5 dBi with high aperture efficiency of 58.3% and a good low-profile characteristic (approximately <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda _{0}$ </tex-math></inline-formula> /6). The measured output power of SCs can reach to 600 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{w}$ </tex-math></inline-formula> . The work proposed in this communication illustrates the multifunctional requirements of antenna with high radiation properties, low profile, and the capability of power harvesting, simultaneously. It may be a good scheme for self-powered occasions, such as outdoor and satellite communication devices.

A broadband Fabry–Perot resonator antenna using partially reflecting surface with positive reflection phase gradient

A novel Fabry–Perot resonator antenna with a wide impedance- and gain-bandwidth is proposed in this paper. A wideband aperture-coupled microstrip antenna is used as the primary source, and a single-layer frequency selective surface with a positive reflection phase gradient is designed as a partially reflective surface. To validate the proposed approach, a prototype antenna operating in the X-band is designed, fabricated, and measured. Both simulation and measured results indicate that the proposed antenna exhibits wideband characteristics. The measured impedance bandwidth (|S11| &amp;lt; −10 dB) is 64.4%, ranging from 8.68 to 15.12 GHz. The experiments demonstrate that a 3 dB gain bandwidth of 31.9% from 8.61 to 11.80 GHz with a peak gain of 14.0 dBi at 10 GHz is achieved. In addition, the proposed antenna reveals good directional radiation patterns, low side-lobe level, and low cross-polarization over the whole working band.

A novel method for high‐gain and high‐aperture efficiency Fabry‐Perot resonator antenna design

Due to the nonuniform electric field distribution over its aperture, the Fabry-Perot resonator antenna (FPRA) is normally with high gain but relatively low-aperture efficiency. In this paper, a novel nonuniform superstrate design method is proposed to improve the gain and aperture efficiency of the FPRA. The reflection amplitude design formula of the superstrate for uniform electric field distribution is derived. Based on this formula, a nonuniform superstrate with different reflection amplitudes and a fixed reflection phase is designed to uniformize the aperture electric field distribution and maximize the aperture efficiency of the FPRA. As a verification of this design method, a FPRA working at 10 GHz with the aperture size of 3.5 × 3.5 λ is designed, fabricated and measured. The simulated gain of the nonuniform FPRA is 21.6 dBi at 10 GHz with the aperture efficiency as high as 93.9%.

High Gain and Wideband Fabry-Perot Resonator Antenna Based on a Compact Single PRS Layer

In this paper, a wideband and high gain Fabry Perot Resonator Antenna (FPRA) is proposed. It is based on a synthesized compact single partially reflective surface (PRS) layer acting as a superstrate to a slot-coupled feed antenna, which acts as a radiating source element for the proposed design. The PRS is based on a 2-D printed unit cell, where the lower part is a simple circular ring Frequency Selective Surface (FSS), incorporated with a synthesized FSS unit cell, using an automated system through a VBA based interface established between CST Microwave studio and Matlab, and optimized using a binary genetic algorithm. This new FSS layer acts as the upper part of the proposed PRS layer and provided a positive phase gradient. It almost perfectly resembles that of the optimum PRS over the desired frequency range, with a relatively high reflection magnitude, which makes it a promising superstrate candidate for wideband and high gain FP resonator antennas. The fabricated prototype achieved an important performance in terms of impedance bandwidth with 42%, ranging from 11.32 to 17.35 GHz. In addition, the 3-dB gain bandwidth is 36 % from 11.68 to 16.78 GHz, with a maximum peak gain of 14.72 dB achieved at 16 GHz. Consistent and almost invariant radiation patterns are achieved over the Ku-band frequency band of interest. The experimental and simulated results are in good agreement, justifying the feasibility of the proposed design as a high gain and wideband FP resonator antenna.

Circularly Polarized FP Resonator Antenna With 360° Beam-Steering

A high gain circularly polarized Fabry–Perot (FP) resonator antenna with 360° beam steering property is presented in this communication. A linear to circular polarization conversion metasurface (PCM) based on a receiver–transmitter unit cell is designed to act as the partially reflecting surface (PRS) of the FP resonator antenna. The transmission phase of the unit cell can be tuned by rotating the radiator and transmission phase shift of the unit cell equal to the rotation angle of the radiator, indicating that the transmission phase varies over a range of 360°. Then, by manipulating the transmission phase of unit cells on the metasurface (MS), the antenna can realize 360° beam steering with an angle tilted range of 0°–75°. To further enhance the antenna performance, the compensatory transmission phase is added to each unit cell on the MS, which can make the antenna obtain higher gain while realizing tilted beam. The measured results of the fabricated antennas imply the feasibility of this design. The proposed MS provides a novel method to realize beam steering of the circularly polarized FP resonator antenna.

A novel receiver-transmitter metasurface for a high-aperture-efficiency Fabry-Perot resonator antenna* *Project supported by the National Natural Science Foundation of China (Grant No. 61871394) and Natural Science Foundation of Shanxi Province, China (Grant No. 2020JQ-482).

This paper presents a novel coupled receiver–transmitter metasurface (MS) which is used to realize a high-aperture-efficiency Fabry–Perot resonator antenna. The unit cell of the MS adopts a slot-coupling procedure to realize energy transmission from the receiver patch to the radiator patch. This approach makes it easier to independently control the transmission magnitude and phase. Based on this characteristic, the transmission coefficients of different unit cells on the MS can be optimized by a genetic algorithm. Then, nearly uniform electric amplitude and phase distribution across the aperture field of the antenna are achieved. Therefore, the gain and aperture efficiency of the antenna are improved. A prototype of the optimized antenna is fabricated and measured to validate the design. The measured gain of the fabricated antenna reaches 17.3 dBi with an aperture efficiency of 94.5%. A higher aperture efficiency is obtained with the proposed antenna which has a low profile and simple structure.

Fabry-Pérot Resonator Antenna in Equivalent-Medium Metamaterials

In this communication, a wideband Fabry–Perot resonator antenna (FPRA) is proposed. An optimized partially reflective surface (PRS) with a transverse permittivity gradient (TPG) composed of four nonrotationally symmetric sections is employed in the design of the antenna. The use of nonrotationally symmetric PRS results in more than 31% improvement of the 3 dB gain bandwidth compared with the traditional rotationally symmetric PRS. Furthermore, two types of nonresonant metamaterials (metallic-ring and etching-hole unit cells) are used to implement the equivalent permittivity of PRS. In this way, the equivalent permittivity value covers a broad range (3.5–9.5) for the same dielectric. As a result, the restrictions imposed by the use of only commercially available dielectrics and the errors that occur during the fabrication and assembly progress of different materials can be avoided. The primary radiator of FPRA is a double-ridge waveguide horn, which ensures wideband antenna operation. An FPRA prototype is fabricated and measured, which exhibits a broad bandwidth (5.2–11.5 GHz) with the return loss |S11| of less than −10 dB. The measured 3 dB gain bandwidth is 73.8% (in the frequency range of 5.3–11.5 GHz) with a peak gain of 17.1 dBi at 7.8 GHz.

Gain and AR Improvements of the Wideband Circularly Polarized Fabry-Perot Resonator Antenna

A method to improve the performance of a wideband circularly polarized (CP) Fabry–Perot resonator antenna (FPRA) is presented in this communication. First, a wideband CP FPRA composed of a partially reflective surface (PRS) with a positive reflection phase gradient and a wideband CP patch antenna is proposed. Then, a transmission metasurface (MS) with a high transmission magnitude and tunable transmission phase in a broadband range is proposed to correct the electric field phase above the antenna. This MS has the ability to independently tune the transmission phases of two orthogonally polarized waves. On the one hand, the nonuniform phase distribution on the aperture field of the antenna can be transmitted to be nearly uniform, so the gain of the antenna will be enhanced. On the other hand, the transmission phases of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$x$ </tex-math></inline-formula> - and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$y$ </tex-math></inline-formula> -polarized waves are corrected to maintain a 90° phase difference at every position, which leads to a wider axial ratio (AR) bandwidth. Therefore, after the phase correction of the MS, the gain and AR performances of the antenna are both improved significantly. The measured results suggest that the overlap of the 10 dB return loss bandwidth, 3 dB gain bandwidth, and 3 dB AR bandwidth of the antenna is 9–11.1 GHz (21%). The peak gain of 18.3 dBic is achieved at 10.2 GHz. The results indicate that the proposed MS can achieve excellent performance improvement of the CP FPRA.

Wideband and Compact Fabry–Perot Resonator Antenna Using Partially Reflective Surfaces With Regular Hexagonal Unit

A wideband and compact Fabry–Perot resonator antenna (FPRA) employing two layers of partially reflective surfaces (PRSs) is presented in this letter. The proposed PRSs with regular hexagonal units are used in wideband FPRA for the first time. Based on the compact arrangement of regular hexagon units and the addition of tripod branches, the size of FPRA is greatly reduced. Furthermore, the regular hexagonal units are arranged periodically along three directions on the 2-D plane, which means that one regular hexagon unit has six identical units around it. Therefore, there is a strong coupling between the PRS units, and units obtain a positive phase gradient in a wide range of 9.1–13.5 GHz, which is the basis for the formation of the wideband FPRA. The FPRA with dimensions of (2.2×2.2×0.6) λ03 (λ0 is the wavelength of the center frequency) has a 3 dB gain bandwidth over 9.2–13 GHz, relatively 34.2%, with a peak gain of 14.2 dBi. The prototype has been fabricated and tested, and validate the simulated results.

3D printing conformal metasurface for Fabry‐Perot resonator antenna application

A conformal receiver-transmitter metasurface (MS) for high gain conformal Fabry-Perot (FP) resonator antenna is presented in this article. The meta-atom consists of three layers of metal structures and two layers of supporting structures. The three layers of metal structures, including receiver patch, radiator patch and ground plane, are printed on ultra-thin substrates. The reception and radiation of the meta-atom are separated by the ground plane, in which case, the reflection and transmission coefficients of the meta-atom can be tuned independently. This property enables the MS to realize transmission phase compensation while maintain the reflection coefficient constant. Also, the supporting structures are fabricated by 3D printing technology, thus they can be fabricated into cylinder and the metal structures on ultra-thin substrates are easily conformed to them. A conformal patch feed antenna is designed in the same way. Then the conformal FP resonator antenna is formed by the MS and the feed antenna. Through tuning the transmission phase of each meta-atom, the MS can make the wave coming out of the cavity appear as a nearly plane wave. The peak gain of the conformal FP resonator antenna reaches 18 dB with aperture efficiency of 58.5%. Fine radiation pattern and high gain property are obtained by the conformal resonator antenna. The measured results verify the performance of the proposed conformal antenna. The design in this article can greatly promote the practical application of the FP resonator antenna.

Dual Circularly Polarized Fabry–Perot Resonator Antenna Employing a Polarization Conversion Metasurface

A dual circularly polarized (CP) Fabry-Perot (FP) resonator antenna is presented in this paper. A linear to circular polarization conversion metasurface (MS) is employed as the superstrate of the FP resonator antenna. The working principle of the unit cell adopted by the MS enables it to independently control the transmission and reflection characteristics. Firstly, the MS is designed to present high reflectivity to ensure the high gain of the FP resonator antenna. Then the capability of polarization conversion is endowed to it. The square patch of the unit cell can receive two orthogonal LP waves, and the cross slot on the ground plane can also make them get through. Meanwhile, the circular patch with 45° tilted etched slot can radiate different CP waves when excited by different LP waves. Therefore, the proposed MS can combine the function of partial reflection and transmission polarization conversion. And for different LP waves, the MS can convert them into different CP waves. A dual LP microstrip patch antenna is designed to act as the feed of the resonator antenna. When the antenna is fed at different ports, different LP waves are excited in the resonant cavity and are converted into different CP waves by the MS, thus the antenna obtains dual CP radiation. The measured results indicate that the antenna can exhibit excellent dual CP radiation characteristic. Compared with other reported dual CP resonator antennas, the proposed antenna can obtain well performance with simple structure and low profile.

Wideband Fabry–Perot Resonator Antenna Employing Multilayer Partially Reflective Surface

A method for designing wideband Fabry–Perot resonator antennas (FPRAs) using multilayer partially reflective surface (PRS) is presented. The proposed partially reflecting structure employs a pair of closely spaced PRSs to obtain a positive reflection phase gradient over a wide range of frequencies. Each PRS layer is composed of complementary square apertures and patches printed on either side of a thin dielectric sheet. The distance between the two PRS layers is only $\lambda _{\mathrm {o}}/12$ ( $\lambda _{\mathrm {o}}$ being wavelength at the center frequency of 13 GHz). Due to the presence of strong couplings between the two PRS layers, the designed PRS unit cell gives a positive reflection phase gradient from 11 to 15 GHz, thereby forming the basis of a wideband FPRA. Based on the proposed PRS, a compact FPRA with overall dimensions of $2.4\lambda _{\mathrm {o}} \times 2.4\lambda _{\mathrm {o}} \times 0.66\lambda _{\mathrm {o}}$ is designed and experimentally validated, which gives a 3 dB gain bandwidth and a maximum realized gain of 32.3% and 14 dBi, respectively.