H-plane Horn Antenna Research Articles

Electronic Beam-Scanning Strip-Coded Graphene Leaky-Wave Antenna Using Single Structure

In this paper, a reconfigurable graphene leaky-wave antenna (GLWA) with electronic beam scanning capability for THz communications system is proposed. It consists of graphene strips printed on silicon oxide substrate and is fed by a planar H-plane horn antenna. The tunable graphene conductivity using DC-bias is used to control the GLWA-radiated beam direction without changing its physical structure. By selecting the proper periodicity of the biased/unbiased graphene strips (i.e., codes) of the GLWA, the beam direction, scanning range, gain, and SLL are changed without changing the array layout. A parametric study on the effect of GLWA dimensions on the radiation characteristics is studied. The radiated beam is electronically scanned from − 68° to 26° at a fixed frequency of 2 THz using different codes. The proposed antenna is simple in design, easy to control via the bias/unbiased periodic graphene strips. It has a compact size of $$1350\times 300\times 35 {{\mu m}}^{3}$$ . The GLWA coded by 1111111000 has a peak gain of 19.7 dBi, SLL of − 10.8 dB and beam radiated in 8° direction at 2 THz. The code 11111000 has beam scanning from − 35° to − 3° with frequency varying from 1.8 to 2.2 THz with 20.0 dBi gain. An investigation of the radiation characteristics of different codes of GLWA is introduced. The effect of GLWA feeding with substrate integrated waveguide (SIW) H-plane horn antenna that is compared with the ideal wave-port is studied. The GLWA with code 11111000 introduces BW of 21.95% (1.72–2.15 THz) with good impedance matching. The antenna structure is full-wave simulated and studied using the finite integral technique.

Dielectric‐loaded substrate integrated waveguide H‐plane horn antenna with embedded air cavity

A new type of dielectric-loaded substrate integrated waveguide H-plane horn antenna with an embedded air cavity is proposed aiming to improve E-plane performance on a thin substrate. Comparing with recent works, this design attracts superior radiation performance only requiring drilling process to embed a rectangular air cavity in the extended dielectric loading. The measurement results show that at 24.15 GHz, the proposed antenna provides a gain of 13 dBi and 27.7 dB front-to-back ratio with narrow 34.3° and 27.3° half-power beamwidths in E- and H-plane. From 22 to 27 GHz, the side lobe level in E-plane is reduced below −10 dB. The entire proposed antenna size is 59 × 16 × 3.175 mm.

Dual-Polarized Directive Ultrawideband Antenna Integrated With Horn and Vivaldi Array

A novel ultrawideband dual-polarized H-plane horn antenna incorporated with a Vivaldi array is proposed. Aiming at ultrawide low-frequency applications that require dual-polarization with a compact shape, the proposed antenna employs an all-metal shared aperture structure. Different from the conventional dual-polarized horn where dual polarization is achieved using two orthogonal modes of the same waveguide, the proposed antenna uses two different types of transmission line for feeding: rectangular waveguide for vertically polarized (VP) H-plane horn antenna, and slot line for horizontally polarized (HP) Vivaldi antenna array. The Vivaldi slot significantly increases the HP bandwidth compared to the typical dual-polarized horn antennas, and does not disturb the VP radiation pattern. The proposed antenna has a measured -10 dB impedance bandwidth of 103% for HP mode, and 77.5% for VP mode. The measured peak gain for HP is 13.0 dBi and 14.3 dBi for VP. The simulated and measured results are in good alignment.

Dielectric-Loaded SIW H-Plane Horn Antenna With Gradient Air Slots

In this letter, a new structure of a dielectric-loaded substrate integrated waveguide H-plane horn antenna with gradient air slots, fed by a coaxial pin, is proposed. This novel structure aims at improvements in the radiation characteristics, including the gain, front-to-back ratio (FTBR), both E- and H-planes half-power beamwidth (HPBW), and sidelobe level (SLL). The measurements of the fabricated antenna show 15.4 dBi gain, 37 dB FTBR, and narrow E- and H-plane HPBW of 35° and 27° respectively, at 24.15 GHz. The entire antenna structure design is briefly expressed to combine the advantage of one single Rogers TMM4 thermoset laminate layer for reduced manufacturing difficulties and ensured improved performance. The optimized proposed antenna is fabricated by standard printed circuit board (PCB) manufacturing process, with the overall size 61.2 mm × 18.6 mm × 3.175 mm.

Horn Antenna With Miniaturized Size and Increased Gain by Loading Slow Wave Periodic Metal Blocks

An H-plane horn antenna with miniaturized size and increased gain is reported, which is realized by loading slow wave structures (SWSs) inside the shortened horn cavity. The SWSs in the form of periodic metal blocks can decelerate the phase velocity of the electromagnetic wave traveling to the radiating aperture. So the phase difference between the center and the edges of the aperture enlarged by the shortened longitudinal dimension can be compensated, and the longitudinal length of the horn antenna is significantly reduced. Meanwhile, uniform magnitude distribution of electric fields on the aperture is achieved by cleverly designing the heights of embedded blocks. Thus, the realized gain and aperture efficiency are maximized. The proposed horn antenna is easily fabricated by standard mechanical manufacture process. The longitudinal length of the prototype is 33.3% less than the original horn antenna with the same aperture size. Moreover, the average gain is 1.7 dB higher than the original horn, while maximized aperture efficiency up to 80.7% is achieved.

A single layer SIW H-plane Horn Antenna with nearly equal E- and H-plane beamwidths

ABSTRACT In this paper, a novel Single-layer Substrate Integrated Waveguide (SIW) H-plane horn antenna with equal beamwidths in the principal planes is proposed. To equalize radiation patterns in E- and H-plane, descending tapered-length triangular grated transitions are used at the aperture of the horn. Then, an elliptical dielectric slab with ascending tapered-diameter air holes is utilized to improve the gain and bandwidth of the antenna. Its radiation patterns in E- and H-plane are nearly equal and the H-plane planar horn antenna works as a 3D pyramidal horn. The antenna has small dimensions of 76.62 mm × 22.9 mm × 3.175 mm (5.62λ0 × 1.68λ0 × 0.23λ0). It covers the frequency range of 17 GHz-26 GHz with S11 < −10 dB, i.e., 41% bandwidth. The gain of the antenna is 12.6 dBi ± 2.5 dBi over the operational bandwidth. The proposed horn antenna is a suitable feed for small symmetric reflectors with negligible blockage and respectable efficiency. To validate the simulation results, the antenna is fabricated and tested. There is a good agreement between the simulation and measurement results.

Reconfigurable Dual-Fed Horn With Pattern Switchability Realized by SIW Technology

A novel multihorn antenna using the substrate integrated waveguide (SIW) technology is discussed in this communication. Conventional SIW-inspired horns, being the extensions of planar H-plane horn antennas, portray a fan-shaped beam, with a narrow H-plane and a wide E-plane radiation characteristics. The present design employs this feature to produce a crossed horn, in which both E- and H-plane radiations can be realized by individually exciting the two sectoral horns, while terminating the other port to a matched load. When both the ports are excited, a spot beam is realized, representing a pattern similar to that of a pyramidal horn. Such an antenna should find its potential applications in systems requiring radiation switchability/pattern diversity from a single embodiment.

Dielectric-Slab-Loaded Hollow Substrate-Integrated Waveguide $H$-Plane Horn Antenna Array at $Ka$-Band

A dielectric-slab-loaded hollow substrate-integrated waveguide (HSIW) H-plane horn antenna with improved impedance matching is proposed based on printed circuit board material FR-4. HSIW is utilized to avoid high dielectric loss. Apart from that, a dielectric slab is added by directly extending the substrates for gain improvement. Moreover, two coupling lines are added above and below the horn aperture for better impedance matching. The proposed HSIW H-plane horn antenna shows a maximum realized gain of 11.2 dBi with 77.6% radiation efficiency and 32.9% bandwidth (27.7-38.6 GHz). Based on the antenna element, a 1 × 4 HSIW H-plane horn antenna array is proposed. The array shows a maximum realized gain of 17.2 dBi with 66.5% radiation efficiency and 31.9% bandwidth (27.6-38.1 GHz). Good agreements of the measured and simulated results are achieved for both designs. The proposed antenna and array can be good candidates for low-cost millimeter-wave wireless communication systems.

Substrate Integrated Waveguide Corrugated Horn Antenna

In this paper, a substrate integrated waveguide (SIW) H-plane horn antenna is proposed. We first optimize the antenna in size to obtain the maximum gain. The SIW horn antenna is then corrugated by adding some vias in order to further improve the beam pattern. We use half power beam width (HPBW) as a metric for this improvement. An optimization procedure is also employed to find the best places for the added vias. The horn antenna is implemented on FR4 substrate at 27 GHz frequency band for both with and without corrugation. The results show a good agreement between simulation and measurement. Moreover, it is shown that the SIW corrugated horn antenna reveals a pattern enhancement in terms of HPBW.

Gain and Bandwidth Improvement of Empty Substrate Integrated Waveguide H-plane Horn Antenna at W-band

A high-gain broadband empty substrate integrated waveguide (ESIW) H-plane horn antenna constructed by four low-cost printed circuit board (PCB) layers is proposed in this paper. The empty structure is fabricated by using high-precision laser engraving technology. A slotted rectangular dielectric load (SRDL) is introduced by simply extending the substrates, resulting a 4-dB gain enhancement and a 31% bandwidth improvement. The proposed antenna gives a measured realized gain at 14.5-dBi level with a relative impedance bandwidth larger than 19.6% (|S11| ≤ − 10 dB). The proposed antenna features the merits of low cost, high gain, and broad bandwidth.

Design of compact omnidirectional substrate integrated waveguide exponentially tapered multiple H-plane horn antenna

This paper describes a compact omnidirectional antenna on a cylindrical substrate for possible application to indoor wireless communication systems operating at 18 GHz. The proposed antenna consists of nine exponentially tapered substrate integrated waveguide (SIW) H-plane horns at an angular separation of 40° from each other. A pair of metallic vias has been introduced between the horns to obtain satisfactory reflection loss. The proposed structure is symmetrical and is excited by a central probe feed. This symmetry brings about equal electric field distribution in all the horns, which leads to an omnidirectional pattern with appreciable gain (9.5 dBi in simulation). A fractional bandwidth (FBW) of 0.95% has been obtained at the resonant frequency. The design has been fabricated and tested against simulated data, wherein good agreement has been observed. The proposed structure is of low profile having a diameter 80 mm (4.8λ0) and height 0.5 mm (0.029λ0).

Conformal platform‐embedded horn antenna with ultra‐wide bandwidth and low profile

This article presents an H -plane horn antenna exhibiting very wide bandwidth, low profile, and nearly end-fire radiation. A wideband coaxial-to-waveguide transition is proposed by employing ridged waveguide and metallic posts in order to enhance the bandwidth and to suppress the higher mode, respectively. An ellipse-shaped copper taper is extended along the horn aperture in order to obtain smooth transition from the aperture to free space. The proposed antenna can be fully embedded in a conducting platform. Simulated results show that the proposed conformal antenna achieves a very wide bandwidth from 3.4 to 18 GHz for VSWR ≤ 2.5 while retaining the antenna height of only 5.508 mm (0.062 λ 0 at the lowest operating frequency). Nearly end-fire radiation is obtained over the whole frequency band. The prototype of the conformal configuration with six antenna elements embedded into a large cylindrical platform is fabricated and tested, measured results are in good agreement with simulated ones.

High gain and wideband substrate integrated waveguide based H-plane horn antenna

A substrate integrated waveguide (SIW) based H-plane horn antenna with high gain and larger operating bandwidth is proposed in this article in a cost-effective way. An air layer is introduced between the top and bottom surfaces to increase the gain by reducing the effective dielectric constant. Extended metal circular patches with horn aperture are adopted to increase the gain of the horn antenna. Metalized via posts are used in front of the aperture to deal with the impedance mismatch issue. Moreover, air-vias are incorporated periodically into the extended dielectric slab to enhance the bandwidth. The proposed antenna is of the dimension 42 mm × 18.6 mm × 4.8 mm. The antenna operates over 20.6–21.2 GHz, 23.0–26.1 GHz and 27.4–28.2 GHz with a measured peak gain of 11.25 dBi at 20.9 GHz. The proposed antenna is fabricated and measured to validate the simulated results and it shows good agreement.

Design and Development of High-Gain SIW H-Plane Horn Antenna Loaded With Waveguide, Dipole Array, and Reflector Nails Using Thin Substrate

In this communication, a new probe-fed substrate integrated waveguide (SIW) H-plane horn antenna including three linear dipole arrays is proposed. To feed the dipole arrays, a portion of a rectangular waveguide is placed at the front of the radiating aperture of the SIW horn in conjunction with two slots, which are etched at the top and bottom of the substrate. A row of reflector nails is also added to reduce the backward radiation and to improve the antenna gain. A prototype of the proposed antenna is fabricated using the printed circuit board process. The proposed antenna is numerically investigated by a software package. The simulated and measured results are reported for verification. The measured results show that the proposed antenna provides 13.97 dBi gain at 20.5 GHz with a low backward radiation.

Development a new wideband substrate integrated waveguide H-plane horn antenna loaded with periodically diamond patches

This paper presents a new wideband Substrate Integrated Waveguide (SIW) H-plane horn antenna. A few rows of diamond patches are printed on the top and bottom side of the dielectric slab at front of the radiating aperture of a conventional horn to improve impedance matching. The proposed antenna is numerically investigated using a software package and a prototype of the antenna is made to validate the obtained simulated results. The measured results show that the introduced antenna provides 22.7% impedance bandwidth, which covers from 20.8 GHz to 26.15 GHz with stable end-fire radiation patterns, while Side Lobe Level (SLL) is lower than −10 dB over the operating bandwidth.

Multi-Way Quasi-Optical Waveguide Power Divider with 2D Diffraction Approximation and Experimental Verification at Millimeter Wave

In this paper, multi-way quasi-optical parallel-plate waveguide power dividers/combiners are designed and fabricated using the 2D diffraction approximation. Shape optimization technology is applied to shape the cylindrical reflector surface to reconstruct the diffraction field to improve the magnitude and phase balance of the parallel-plate waveguide power dividers. Both a 1-to-6 way quasi-optical waveguide power divider with H-plane horn antenna array and a 1-to-10 way power divider with gap waveguide transition are analyzed and designed, respectively. We fabricated the two designed power devices at millimeter wave for verifying the validity of the design method. The measured average transmission coefficient of the 1-to-6 way power divider is − 10.8 dB from 81 to 110 GHz, corresponding to 50% power combining efficiency, while the measured back-to-back structure of the 1-to-10 way power divider/combiner features an average transmission coefficient to − 2.83 dB corresponding to 72.2% power combining efficiency over the entire W-band. The proposed power dividers/combiners and the efficient optimization method used in their design are believed to be of importance for future power device applications in millimeter wave and terahertz range.

Compact High-Performance Lens Antenna Based on Impedance-Matching Gradient-Index Metamaterials

A planar wavefront transformation lens based on gradient-index metamaterials is proposed. The designed lens is composed of isotropic and inhomogeneous metamaterials and can reach impedance matching with free space. Based on the impedance-matching metamaterial lens, we present a compact high-gain and high-aperture-efficiency horn-based lens antenna working from 8 to 12 GHz. At the center working frequency of 10 GHz, the performance of the antenna is significantly improved and the measured gain increases to 17.7 dBi, which is 6.5 dBi higher than that of the original H-plane horn antenna. The half-power beamwidth and sidelobe level in the H-plane reduces to 6.2° and 15.3 dB, respectively, and the aperture efficiency reaches 94%. Such performance is much better than that of the conventional optimal H-plane horn antenna.

A 18–40 GHz Substrate Integrated Waveguide H-Plane Horn Antenna

A 18-40 GHz wideband substrate integrated waveguide (SIW) H-plane horn antenna is proposed for applications on both the K- and Ka-bands. By employing a grating transition in front of the horn aperture, the impedance bandwidth (IBW) of the proposed antenna is broadened considerably. A broadband double-ridge waveguide (DRW)-to-SIW transition is also developed as the feeding structure for the proposed SIW H-plane horn antenna. The DRW is adopted to support a wider IBW as compared to that of a rectangular waveguide. A prototype of the proposed antenna is experimentally verified. The measured results show that the IBW for |S <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> | ≤ -10 dB ranges from 18 GHz to more than 40 GHz, covering the entire Kand Ka-bands. The measured gain varies from 7.52 to 15.37 dBi with an average gain of 11.58 dBi. In addition, the endfire radiation patterns are observed and maintained within the IBW.

Quasi-corrugated substrate integrated waveguide H-plane horn antenna with wideband and low-profile characteristics

A wideband H-plane horn antenna based on quasi-corrugated substrate integrated waveguide (SIW) technology with a very low profile is presented in this article. Open-circuited microstrip stubs are applied to create electric sidewalls of the quasi-corrugated SIW structure. The quasi-corrugated SIW H-plane horn antenna shows high performance and simple structure. A specify-shaped horn aperture is utilized, so that the poor impedance matching owing to the structure restriction can be smoothened. The structure is simulated by ANSYS HFSS and a prototype is fabricated. The measured results match well with the simulated ones. An enhanced impedance bandwidth ranging from 5.3 GHz to 19 GHz (VSWR < 2.5) is achieved. The presented antenna also brings out stable radiation beam over the same frequency band.

Bandwidth and Gain Enhancement of Ridge Gap Waveguide H-Plane Horn Antennas Using Outer Transitions

In this communication, solutions are developed for gain and bandwidth enhancement of a ridge gap waveguide (RGW) H-plane horn antenna. Intrinsic features of RGW allow us to introduce a simple transition at the antenna aperture making its impedance matching with outer space easier, leading to antenna bandwidth enhancement. Two transitions, stepped and tapered, are introduced. The proposed transitions are fully designed as a part of horn flared part and do not introduce any expansion to the antenna length, contributing to its compactness. Furthermore, the modified form of the proposed RGW H-plane horn in which the antenna aperture is squinted is also presented. In this form, the backward radiation is reduced leading to 2 dB gain enhancement.