Horn Radiation Research Articles

A 3-D Printed Lightweight Miniaturized Dual-Band Dual-Polarized Feed Module for Advanced Millimeter-Wave and Microwave Shared-Aperture Wireless Backhaul System Applications

A 3-D-printed lightweight miniaturized dual-band dual-polarized feed module of wireless backhaul systems consisting of a dual-band air-filled waveguide orthomode transducer (OMT) and a shared-aperture conical horn radiator is investigated. The OMT operating in both Ku- and E-bands with a large frequency ratio is realized by combining the turnstile-junction-type and Bøifot-junction-type OMTs sharing a common-mode-composite coaxial port. A design method of the dual-band OMT considering the requirement for a self-supporting geometry in metallic 3-D printing is presented, so that its compact configuration that is difficult to fabricate by traditional milling technology can be fulfilled conveniently in a whole piece with the use of commercial 3-D printing facilities. A millimeter-wave horn with a small radiation aperture is embedded into a larger aperture of a microwave horn. A proper longitudinal offset between them is introduced to guarantee promising radiation characteristics of the shared-aperture scheme in the two bands. By connecting the OMT with the radiator, the proposed dual-band dual-polarized feed module with a weight of only 100 g is manufactured and measured. Excellent performance, involving the wide bandwidths of 46.7% and 31.2% at microwave and millimeter-wave frequencies, a high isolation of almost larger than 40 dB, a high radiation efficiency of about 90%, and stable dual-polarized radiation patterns with low cross polarizations, is confirmed experimentally. Benefitted from the geometric and operating merits, the feed module would be attractive for applications in advanced millimeter-wave and microwave shared-aperture wireless backhaul systems.

The Results of the Experimental Study of the Method of Directional Radiation Pattern Transformation of a Conical Horn Radiator Operating in Millimetric (Sub-THz) Band

The article describes the experimental study of one of techniques of implementation of a machine-vision illuminant operating within the millimetre (sub-THz) band and forming a directional radiation pattern (DRP) with parameters compliant with the specifics of functioning of radio vision systems. In view of this, experimental research of the method of formation of a DRP configuration of a millimetre (sub-THz) machine vision system illuminant based on a conical horn radiator adapted to receiver field of view was studied experimentally using a quasi-optic system. The results of the study of the DRP configuration of such illuminant designed using a quasi-optic system installed in the aperture of a conical horn radiator are presented.

Experimental study of the transmission of energy of a microwave electromagnetic field into the oil environment employing a submersible emitter

The supply of heat to oil media pumped by pipeline transport systems is one of the main problems in the oil industry. The article describes a method for supplying heat to oil-containing media using the energy of an electromagnetic field. The possibility of releasing surfaces in contact with oil sludge under the influence of electromagnetic fields has been shown by experiment. We describe the design and parameters of a biconical horn radiator of a microwave electromagnetic field operating at a frequency of 2 450 MHz. A method for generating energy and transmitting it to the emitter by means of a coaxial cable is shown. Testing the emitter in oil placed in an optically transparent and radio-tight double-walled tank is presented. The design of the stand allows us to safely examine the thermal process using a thermal imager. The installation made it possible to heat 7 liters of oil at 15 °C in 12 minutes.

Ultra-Wideband Endfire Long-Slot-Excited Phased Array for Millimeter-Wave Applications

An ultra-wideband phased array with endfire radiation is proposed for millimeter-wave (mm-wave) applications. This array consists of a linear long slot array (LSA) source and a transverse-electromagnetic (TEM) horn radiator. For each unit, a Γ-shaped probe based on a substrate integrated coaxial line (SICL) is adopted to generate a primary slot source. Then, the slot flares in the E-plane with an exponential profile to form a horn unit. The antenna unit is studied with periodical boundaries (PBs) in simulation and operates from 15.4 to 46.4 GHz with active standing wave ratio (SWR) <; 3 for a scan angle of up to 45° in H-plane. To verify the design concept, two 1×16 finite arrays, Array-1 for 0° scan and Array-2 for 45° scan, are fabricated and tested. Over the operating band of 15.4-46.4 GHz, both arrays obtain good impedance matching in measurements with SWR <; 2.3. The measured gain varies from 11.8 to 19.1 dBi for Array-1 and from 10 to 16.9 dBi for Array-2 within 16-40 GHz. Besides, Array-2 exhibits a scan angle of 48° and an average scan loss of 2.4 dB. Moreover, both arrays achieve a radiation efficiency exceeding 73% because of employing the low-loss SICL feed network.

Low sidelobe level circularly polarised monopulse slot waveguide antenna array for Ka‐band application

A circularly polarised (CP) monopulse waveguide antenna array for Ka-band wireless communication is proposed. The antenna structure can be divided into six layers from top to bottom, including radiating layer, aperture layer, cavity layer, aperture layer, feeding layer and monopulse comparator. The upper radiating layer allows two transmission modes of the transverse electric (TE) wave and the transverse magnetic (TM) wave to pass through. The 90° phase difference can be obtained by adjusting the horizontal and vertical angles of the horn radiator, which realises the CP radiation pattern. Besides, the 0° or180° phase difference produced by the monopulse comparator enables the antenna to obtain a monopulse radiation mode. In order to obtain the low sidelobe characteristics, the coupling parameters of the coupling layer are weighted by the Taylor distribution. The overall size of the antenna is 194 × 25 × 31 mm3. The slot waveguide antenna is fabricated and measured to validate the proposed design. The measured results show that the monopulse system can achieve an impedance bandwidth of 3.7% (34.5–35.8 GHz) in the Ka-band at the centre frequency of 35 GHz. The sum-pattern maximum gain and radiation efficiency are 23.3 dBic and 75% at 35 GHz, and the gain of the whole bandwidth is >20 dBic. The axial ratio and the sidelobe level is less than 1.2 and −28 dB, respectively. The difference-pattern amplitude imbalance is <0.2 dB and the null-depth lower than −30 dB. Also, the isolation is better than 30 dB. Besides, the pure metal structure of waveguide has incomparable advantages in a harsh environment.

Conceptual Design of Electromagnetic Pulse for Denied Vehicular Access Application

Modern vehicle architectures are complemented by the use of advanced technologies, primarily in the Engine Control Unit (ECU). This article describes the proposed conceptual design of Electromagnetic Pulse (EMP) for denied vehicular access applications, especially to vehicle (cars) engine ECU. The system mainly consists of five parts, namely power supply, magnetron, isolator, tuner, and pyramidal horn radiator. The magnetron is selected as the means for driving the pulse power generator at an operating frequency of 2.4 GHz. The pyramidal horn radiator with a gain of 15 dB is designed using CST Microwave software and fabricated as well as tested. The performance tests of the designed system are conducted in a laboratory environment and field trials, respectively. The effects of the EMP to the engine ECU are analyzed and discussed in terms of the radiated power, radiation gain, radiation pattern, and significant radiation distance. The expected target distance for stopping a vehicle is at least 3m to 5m.

Investigation of Compact Dielectric Monopole Antenna Integrated with 3D Printed Horn for UWB Applications

Abstract A novel broadband portable Dielectric Resonator Antenna (DRA) with integrated unshorted horn and broadside radiation pattern is implemented for ultra-wideband (UWB) and Electromagnetic sensor applications. A rectangular DRA composed of TMM 10i (Dielectric constant 9.8 and loss tangent 0.002) material is mounted over four supporting pillars to separate the DRA from the ground plane. A conical shaped horn with the copper foil conductor is used as a reflector to increase the gain and realize stable radiation pattern over the wide frequency range. The horn and supporting pillars are fabricated by a 3-D printer using light weight thermoplastic composite polymer Poly-Lactic Acid (PLA). The proposed antenna contributes measured VSWR (2:1) impedance bandwidth of 106 % ranging from 6.8 GHz to 22.2 GHz for a Quasi-TM111 mode with a low cross-pol level which ensures its linear polarization. The measured peak gain of the DRA is 7.8 dBi at 14 GHz, while estimated average efficiency is more than 88 %. The measured average group delay of the proposed antenna is ~ 1.5 ns within operation band. The proposed antenna is suitable for UWB operation and other broadband applications having omnidirectional coverage and stable radiation pattern ranging from C-band to K-band.

Theoretical analysis of the radiating system for treatment of ovarian diseases of the cows

Conducted in this article theoretical studies are focused on calculation of the geometry parameters and directional diagram of the radiating system for millimeter wavelength range for intrauterine treatment of ovarian diseases of cattle. Theoretical studies have shown that radiating system for intrauterine treatment of ovarian diseases of the cows can be created based on the hollow dielectric waveguide system coordinated with pyramidal horn radiator and the dielectric lens at the output of waveguide

The study of the amplitudes of the fields excited linear grating horn irradiators

The problem of scattering from a linear grating of horns can be solved only with approximate methods because known mathematical methods allow to obtain solutions only for simple mathematical models for example for the endless arrays of planar waveguides. Other sources include experimental characteristics of the amplitudes of the fields excited in apertures and the fields scattered by such grating, however, the theoretical calculations are not given. The problem determining of the amplitudes of the field excited by horn radiators, for arbitrary incidence of the plane electromagnetic wave is solved in references. However, the applicability of this solution for the linear grating of the horn irradiators (waveguides) is investigated, which in turn hinders the development of antenna arrays with reduced scattered field. Thus, there is the problem of developing methods for the investigation of electromagnetic fields amplitudes excited in aperture of n-th radiator grating when incident to flat electromagnetic wave, properly polarized in the plane of incidence from an arbitrarily specified sources. The methodology of the study of the electromagnetic fields amplitudes, which are excited in n-th radiator linear grating aperture when the incidence of the plane electromagnetic wave polarized normal to the plane of incidence from an arbitrarily specified sources. It is found that under these conditions, aperture will be excited only with the waves of magnetic type – $A^{H\perp}_{+0m_y}$. The amplitude of the waves excited by n-th emitter is virtually identical to the amplitude of the central even with the distance between them. The results can be used to study more complex rectangular antenna arrays consisting of the n-th number of linear.

High‐gain wideband SIW offset parabolic antenna

ABSTRACTA substrate integrated waveguide (SIW) offset parabolic antenna is proposed in this letter. The antenna consists of four main parts: a feeder with a horn radiator, a parabolic reflector, parallel plate metal blocks, and a dielectric load. The configuration of the horn and parabolic reflector is based on the parabolic reflector principle. The parallel plate metal blocks and the dielectric load improve the impedance matching and radiation performance of the antenna. Measured results show that the antenna is very well matched in the V‐band and the gain of the antenna in end‐fire direction varies from 13.2 dBi to 16.8 dBi. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2888–2892, 2016

A method for lowering the level of the backward radiation of a microwave horn radiator

A method for lowering the level of the backward electromagnetic radiation arising at the edge of the output aperture of a microwave horn radiator is proposed and developed. The method is based on excitation of slow surface electromagnetic waves on the exterior side of the aperture edge of the horn radiator and subsequent transformation of these waves into spatial electromagnetic waves traveling in the antiphase with electromagnetic waves of the backward radiation. The method was tested by the example of a pyramidal horn radiator with curvilinear walls of a combined shape. Computer simulation of such a radiator was performed.

Orthomode Transducer and Dual-Polarized Horn Antenna in Substrate Integrated Technology

A dual-polarized system fully implemented in substrate integrated technology is presented. It comprises an orthomode transducer (OMT) with planar excitation schemes for both orthogonal TE10- and TE01-modes and a dual-polarized horn antenna. The whole structure requires only two layers of substrate, and it is based on the extended substrate integrated waveguide (ESIW), which allows the propagation of TEm0- and TE0n-modes. A compact OMT design is proposed along with a procedure to optimize it. The matching and radiation characteristics of a dual-polarized horn antenna fed with this OMT are also studied. The complete structure was manufactured exhibiting an 8.6% bandwidth (13.9-15.15 GHz) where both modes are well matched ( 28 dB). The horn radiation patterns within the frequency range of operation are also similar for both polarizations. The proposed design demonstrates the feasibility of dual-polarized substrate integrated circuits (SICs). This opens the door to new substrate integrated devices as well as to the use of SICs in applications requiring polarization diversity at end-fire. All together, this combined design becomes a promising approach to tackle the increasing demand for capacity in modern communication systems.

Predicting the Performance of Pyramidal and Corrugated Horn Antennas Using ANFIS

This letter presents the development of an adaptive neuro fuzzy inference system (ANFIS)-based model for predicting the performance of a pyramidal and a conical corrugated horn antennas. Different ANFIS-based models were developed. Using these models, horn return-loss characteristics and radiation patterns (copolarization and cross-polarization) can be obtained with great accuracy for any combination of design parameters. The results obtained using ANFIS models were compared to that of the commercial horn antenna design software and found in close agreement. The advantage of the proposed method lies with the fact that, with less time and minimum computational resources, the return-loss and radiation characteristics of a horn antenna under test can be obtained with high degree of accuracy.

Research on Ultra-Wideband TEM Horn Antenna and its Miniaturization

TEM horn antenna is one kind of directional Ultra-wideband antenna with simple structure. Based on the design method of TEM horn antenna, satisfied impedance and radiation character are obtained by simulation and experiment research. On this basis, by means of metal ridged loaded, background dielectric material loaded and distributed lossy metal loaded respectively, the miniaturization character is realized. The simulation analysis results show that load of traditional TEM horn antenna can get efficiently improvement in structure and performance which have widely application foreground in pulse radiation communication system and ultra-wideband radar system.

Conical Horn: Gain and Amplitude Patterns

The conical horn radiation characteristics (gain, aperture phase distributions, loss factors, and amplitude patterns) are revisited based on the spherical and quadratic aperture phase distributions. Calculations of the conical horn gain, using over the aperture either the dominant -mode of a circular waveguide or the modal variations of a conical waveguide, are calculated using the aperture phase distribution represented by spherical and quadratic wavefronts. The gains are compared with the classical data by Gray and Schelkunoff, in an attempt to confirm their validity and accuracy and to determine whether they were derived based on spherical or quadratic phase distribution. In addition, more accurate loss factors, to account for amplitude and phase tapering over the conical horn aperture, are derived which improve the conical horn gain. New formulas for the design of optimum gain conical horns, based on the more accurate spherical aperture phase distribution, are derived and reported, and guidelines are provided for their utility. This paper also introduces a method to calculate accurately the far-zone amplitude patterns in the E and H planes, including those in the far side and back lobe regions, of a conical horn by utilizing geometrical optics and diffraction theory.

Accurate Modeling of Dichroic Mirrors in Beam-Waveguide Antennas

Frequency selective surfaces, also called dichroic mirrors, are usually analyzed assuming a uniform plane-wave excitation. However, when these devices are used within reflector antennas to combine/separate beams at different frequencies, they are often illuminated by corrugated horns, which generate a radiation pattern that cannot be approximated by a uniform plane wave. For this reason, it is important to properly analyze the interaction between the electromagnetic field generated by the horn and the transmission (or reflection) response given by the mirror. To carry out this task, this paper presents an approach based on the plane wave expansion of the field generated by the horn. The effectiveness of the proposed method, which is able to provide the degradation due to the dichroic mirror to the horn radiation pattern for both the co-polar and the cross-polar component, is validated versus measurements.

Dual-Band Horn Array Design Using a Helical Exciter for Mobile Satellite Communication Terminals

A horn array antenna is proposed for dual-band and dual-polarization operation. The array is optimally designed to be used as a feeder in mobile satellite terminals with a hybrid antenna (HA) structure, but it can be also used independently as a phased array. The array has an oval-shaped rim to maximize the efficiency of the HA, and is composed of 20 horn elements in a hexagonal structure. The element has a horn radiator with a conical helix, which is placed inside the horn and excited by two ports for TX and RX at both ends. Therefore, the antenna can be simultaneously operational in the Ka-band TX and K-band RX frequency bands, using a compact structure providing left-hand circular polarization (LHCP) for TX and right-hand circular polarization (RHCP) for RX. The fabricated array is connected with active channel modules having 20 channels each for TX and RX, and it was experimented on within a beam scanning range of -5° to +5° in the azimuth and elevation directions using phase control of the ac tive channel module. The antenna has a minimum gain of 21.7 dBi over the TX band and 19.7 dBi over the RX band over the desired scan region. The maximum pointing error is about 0.32° and the pointing loss is approximately 1.3 dB. In addition to meeting the above RF requirements, the antenna is designed to meet environmental specifications such as wind loads as required for mobile terminals.

Self-Filtering Low-Noise Horn Antenna for Satellite Applications

In this letter, we present the design and the experimental realization of an innovative self-filtering low-noise horn antenna. The proposed radiator consists of the following: a regular WR-62 waveguide connected to a horn antenna, a metallic screen with a vertical slit placed at the section connecting the waveguide and the horn, and a dielectric slab, with metallic omega shapes printed on both faces, placed across the slit. The goal of this design is to reduce the bandwidth of operation of the regular WR-62 horn in order to self-filter the noise captured within the antenna operation band. In the receiving mode, the metallic omega shapes placed across the slit allow transmission only in a narrow frequency band centered around the resonant frequency of the omegas. In such a frequency band, the radiating performances of the proposed antenna are comparable to the ones of a regular WR-62 horn radiator. A proper set of numerical simulations and measurements confirm the effectiveness of the proposed design, which can be successfully used in receiving satellite communication systems.

On the theory and calculation of directional waveguide-horn antennas

Excitation of a horn radiator by the coaxial line connected to the radiator is considered. A finite electromagnetic pulse with the TEM structure propagates in the line. It is shown that cancellation of the symmetry of rotation about the Z axis of the shape of the horn head results in the appearance at the Z axis of the flow of the efficient electromagnetic radiation directed along this axis, which is caused by the conversion of the TEM mode into the modes with linear (near the Z axis) polarization inside the horn. The possibility of control of the calculation accuracy and support of a high accuracy of calculation (which, for the considered examples, is about 0.1% in terms of the energy norm) is demonstrated.

Development of Advanced Design Software for Complex Multimode Antenna Feeding Systems

Ka-band multiple-beam spacecraft antennas (MBA) are a key technological challenge in the design of broadband communication-satellite systems. Due to the very narrow beamwidth of multiple-beam spacecraft antennas, beam pointing is a critical issue, since even very small pointing errors can seriously affect the antenna's performance. Consequently, many of these communications antennas require closed-loop tracking. While full-wave design tools for multimode waveguide components have been well established since the mid-1990s, there was a perceived lack of similarly powerful design tools for multimode horn radiators. In order to close this technological gap, the European Space Agency (ESA) proposed a sponsored research effort, focusing on the development of multimode horn design software. The project was executed by a team consisting of MDA Satellite Systems, Canada, and Mician GmbH, Germany. While the software-requirements specification and its validation was the primary responsibility of MDA, Mician was responsible for the software implementation. This paper summarizes the work performed under this project, and also provides examples of complex multimode feed designs for multiple-beam spacecraft-antenna applications.