Resonator Antenna Research Articles

2.4 G HZ MINIATURISED RECTANGULAR MPA WITH DEFECTED GROUND AND PATCH

This study aimed to develop a miniaturised rectangular microstrip patch antenna with a resonance frequency of 2.4 GHz. In order to achieve this, an initial microstrip antenna's resonance frequency was shifted from 3 GHz to a lower frequency by employing a defective ground structure (DGS) with a triangular-shaped slot into the ground plane. Also Triangular ring slots used defect the patch to improve co- and cross-polarization separation. Finally, a successful downsizing of up to 28% along the length and 18% along the width of the patch is achieved compared to the traditional 2.4 GHz microstrip antenna. The findings of the experiments have been obtained using high-frequency structure simulator software (HFSS). The substrate used in this work is RT/ Duroid 5880, which has a dielectric constant of 2.2 and a thickness of 1.575 mm.

Зависимость уровня искажений выходного сигнала передатчика современных телекоммуникационных сигналов с разделением составляющих от параметров фильтра тракта огибающей

The article investigates the dependence of the envelope elimination and restoration (EER) transmitter out-of-band emissions on the parameters of its envelope path LPF. LPFs of the sixth order with the Cauer structure, having the same degree of clock frequency unwanted products suppression, unilaterally and bilaterally loaded, and optimized LPFs with a smooth transition of the frequency response from the passband to the stopband are considered. It is shown that when the transmitter is operating at a nominal load (broadband antenna), a sharp transition from the passband to the stopband in the envelope path LPF leads to an increase in out-of-band emissions that are separated from the center frequency of the transmitter by the LPF cutoff frequency. The minimum envelope path allowable bandwidth is at least 5 transmitted signal bandwidths when using a Cauer-type LPF with a standard approximation and at least 3.5 bandwidths for an optimized LPF with a smooth transition. For the case of a transmitter operating on a resonant antenna with a limited bandwidth, the dependences of the minimum envelope path filter required bandwidth on the antenna bandwidth and the VSWR value at the edges of the amplified signal band are revealed. It is shown that the use of two-sided loaded filters in the envelope path allows the transmitter to work on antennas with half the bandwidth and reduce the antenna SWR requirements from 1.03 to 1.07. The use of smooth transition filters allows you to reduce the minimum required bandwidth of the LPF by 20% compared to standard filters. The most preferable is the use of a two-sided loaded LPF of the 6th order with a smooth transition, which ensures the operation of the transmitter to the antenna with VSWR = 1.07 at the edges of the transmitted signal band with a minimum LPF bandwidth equal to 5.8 signal bands.

Оценка влияния формы простого микрополоскового излучателя на его широкополосность

Microstrip antennas are one of the most common types of antennas for mobile objects. Compactness, lightness and conformity make their use convenient and in fact the only solution for the rapidly developing industry of wire-less telecommunications. The key disadvantage of such antennas is their narrow bandwidth inherent in all resona-tor type antennas, microstrip antennas being a particular case. Basically, the narrowband nature of such antennas is due to a pronounced frequency dependence of the input impedance, as a result of which a satisfactory quality of natural matching can be achieved in a frequency band measured in units of percent. The paper considers mi-crostrip radiators of simple geometry: rectangular, square, rhombic, triangular, round, elliptical, located on a sub-strate of fixed geometry with the same dielectric. For each shape of the strip geometry, numerical optimization of the strip dimensions and the position of the excitation point is performed in order to obtain the maximum bandwidth of natural matching in VSWR of no more than 2 when con-nected to a 50-ohm feeder. The frequency of 2 GHz was chosen as the central frequency in numerical studies. Cal-culations of the directional characteristics of the most successful variants of microstrip radiators within the matching band are given. It is shown that for a given ge-ometry and parameters of filling the substrate, the most broadband is a microstrip elliptical radiator, the matching bandwidth of which is from 1900 to 2100 MHz, i.e. +/- 5% of the center frequency. The results obtained can be use-ful both in the design of microstrip antenna arrays and in the construction of microstrip multiband antennas, which is especially important for new generation mobile com-munication systems.

Wideband Low-Profile Connected Rectangular Ring Dielectric Resonator Antenna Array for Millimeter-Wave Applications

A wideband low-profile connected rectangular ring dielectric resonator (DR) antenna (DRA) array is presented for millimeter-wave (mmWave) applications. It consists of four rectangular ring DRA elements. The DRA elements are excited by microstrip feedlines through four slots on the ground plane. A slot mode, the DRA <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mathrm {TE}}^{\text {y}}_{1\delta 1}$ </tex-math></inline-formula> mode, and the perturbed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mathrm {TE}}^{\text {y}}_{3\delta 1}$ </tex-math></inline-formula> mode are simultaneously excited, giving a wideband design. To avoid the alignment problem, the DRAs are connected to their adjacent elements through dielectric arms. It is found that the position of the dielectric arms has significant effects on the antenna performance. To demonstrate the idea, a prototype with a dielectric constant of 20.8 was designed, fabricated, and tested for licensed mmWave bands (24.25–29.5 GHz). A reasonable agreement between the measured and simulated results is observed. The measured 10 dB impedance bandwidth ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert \text{S}_{11}\vert \le - 10$ </tex-math></inline-formula> dB) is 31.6% (22.52–30.97 GHz), with a measured boresight realized gain being higher than 8 dBi from 22.5 to 30 GHz. The measured mutual couplings between the DRA elements of the array are lower than −20 dB in the operating frequency range. Furthermore, our prototype has a low profile of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.074~\lambda _{0}$ </tex-math></inline-formula> , where <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> is the wavelength in air at the center frequency.

Design of the Wideband and Low-Height Omnidirectional Cylindrical Dielectric Resonator Antenna Using Arced-Apertures Feeding

This paper mainly discusses the design of wideband and low-height omnidirectional cylindrical dielectric resonator antenna (DRA). It was theoretically found that the TM-mode category of the cylindrical DRA is suitable for the wideband and low-height design using mode-merging method (TM <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{01 \delta }$ </tex-math></inline-formula> and TM <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{02 \delta }$ </tex-math></inline-formula> mode). An improved apertures-fed technique is proposed to excite the TM-mode DRA. The feeding consists of four arc-shaped apertures, and each aperture was fed by the in-phase signal. Based on the E-field distribution, the higher-order TM <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{02 \delta }$ </tex-math></inline-formula> mode of the cylindrical DRA can be excited by adjusting the position of the apertures, and it fuses together with the fundamental TM <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{01 \delta }$ </tex-math></inline-formula> mode to achieve a wideband antenna. Besides, the aperture mode further widen its impedance bandwidth. To demonstrate the idea, a wideband and low-height omnidirectional cylindrical glass DRA was designed for WLAN 5.2-GHz and 5.8-GHz applications. The experimental results show that the proposed low-height DRA ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$h $ </tex-math></inline-formula> = <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.108\lambda _{0}$ </tex-math></inline-formula> ) can achieve an impedance bandwidth of 25.2 % (without aperture mode) and 34 % (with aperture mode), respectively. The bandwidth enhancement of the proposed design is significant, compared to other reported low-height TM-mode DRAs.

Triple-Band Circularly Polarized Dielectric Resonator Antenna (DRA) for Wireless Applications

This paper proposes a new dielectric resonator antenna (DRA) design that can generate circularly polarized (CP) triple-band signals. A triple-band CP DRA antenna fed by a probe feed system is achieved with metal strips structure on side of DRA structure. The design start with conventional rectangular DRA with F shaped metal strips on DRA structure alongside the feed. Then, the F metal strip is enhanced by extending the length of the metal strip to obtain wider impedance bandwidth. Further improvement on the antenna performance is observed by improvised the conventional DRA structure. The method of removing part of DRA bottom resulted to higher antenna gain with triple band CP. The primary features of the proposed DRA include wide impedance matching bandwidth (BW) and broadband circular polarization (CP). The primary features of the proposed DRA include wide impedance matching bandwidth (BW) and broadband circular polarization (CP). The CP BW values recorded by the proposed antenna were ∼ 11.27% (3.3–3.65 GHz), 12.18% (4.17–4.69 GHz), and 1.74% (6.44–6.55 GHz) for impedance-matching BW values of 35.4% (3.3–4.69 GHz), 1.74% (5.36–5.44 GHz), and 1.85% (6.41–6.55 GHz) with peak gains of 6.8 dBic, 7.6 dBic, and 8.5 dBic, respectively, in the lower, central, and upper bands. The prototype of the proposed antenna geometry was fabricated and measured. A good agreement was noted between the simulated and the measured results.

A Low-Cost 3-D Printed THz Open Resonator Antenna

We propose a design of an open resonator antenna to fulfill the requirements of high gain and low cost at 0.1 THz. A planar cavity with a loaded phase-shifting periodic structure is used to imitate a spherical cavity, which helps to support higher order modes and, hence, widen the bandwidth. The design procedure is introduced in detail. With the help of high-precision three-dimensional printing technology, the periodic structure can be manufactured with a relatively lower cost and complexity. Measurements were carried out to prove that the proposed antenna can achieve a 3 dB gain bandwidth of 13% and a peak gain over 16.8 dBi.

A Review Paper on Design and Development of Dielectric Resonator Antenna

A Review Paper on Design and Development of Dielectric Resonator Antenna

Wideband Wide-Beam Hybrid Dielectric Resonator Antenna Using Uniaxial Material

In this letter, a wideband wide-beam rectangular dielectric resonator antenna (DRA) employing uniaxial anisotropic material is presented. To the best knowledge of the authors, the uniaxial anisotropic dielectric is used in wide-beam DRAs for the first time. By tuning the uniaxial permittivity tensor of the rectangular dielectric, the radiation from the top wall of the DRA is enhanced which improves the gain at low elevation angle in the E-plane. Both the feed slot mode and the fundamental <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{TE}_{{111}}^{\mathrm{y}}$</tex-math></inline-formula> mode are merged to broaden the bandwidth. When a grounded substrate is added and four trapezoidal notches are etched on the ground, the half-power beamwidth (HPBW) in the H-plane is broadened. The measured results achieve an impedance bandwidth of 35.7% over a band of 2.65–3.8 GHz with HPBWs of at least 250° and 162° in the E- and H-planes, respectively.

Compact and Broadband Substrate Integrated Dielectric Resonator Antenna Suitable for 5G Millimeter-Wave Communications

Compact and Broadband Substrate Integrated Dielectric Resonator Antenna Suitable for 5G Millimeter-Wave Communications

Advancements, Challenges, and Prospects of Water-Filled Antennas

In the group of liquid antennas, water antennas have attracted tremendous popularity due to the excellent electrical and mechanical properties of water. Pure water is a high permittivity dielectric liquid which comprises high dielectric constant and very low electrical conductivity. While the electrical conductivity of pure water is very low, salt-water has good electrical conductivity. The electrical conductivity of salt-water can be controlled by adjusting the ratio of salt content (salinity) in the water solution. Both pure water and salt water has excellent optical transparency, liquidity, flexibility and easy availability, thus, become excellent candidates in antenna manufacturing. Pure water is utilized as the dielectric component of the antenna and generally used in the development of dielectric resonator antennas, whereas salt-water is used as the conductive part of the antenna replacing metallic conductors. Some antennas have also utilized both the pure water and salt water for improved performance. In the literature, different classes of antennas can be found that have been developed by utilizing water. In this review paper, we have highlighted the state-of-the-art designs of water-filled antennas, highlighted the major challenges towards the development of water-filled antennas and presented the novel applications and prospects of water-filled antennas.

DESIGN AND DEVELOPMENT OF SUPER WIDEBAND DIELECTRIC RESONATOR ANTENNA FOR NEXT-GENERATION TELECOMMUNICATIONS

The dielectric resonator antenna (DRA) has revolutionized the latest generation of communication systems with their obvious advantages of small size, bandwidth, and power-consuming capabilities. In this paper, an analysis of the impact of the dielectric material on the radiation characteristics of the DRA is presented with simulation reports. The proposed antenna takes the shape of a circular patch with the dielectric resonator having different shapes. This helps to analyze the impact of the tapering adjustments on the features of the antenna. The simulations are performed using the latest version of the complex electromagnetic modeling tool, and results are analyzed in terms of simulated reports like reflection coefficient (S11), voltage standing wave ratio, radiation patterns, and field distribution plots. The overall size of the proposed antenna is 18 &amp;times; 12 mm&lt;sup&gt;2&lt;/sup&gt;. The measured results are in good agreement with the simulation results. The proposed DRA is suitable for mobile wireless applications.

MM-Wave High Isolated Dual Polarized Dielectric Resonator Antenna for In-Band Full-Duplex Systems

A novel high-isolation dual-polarized in-band full-duplex (IBFD) dielectric resonator antenna (DRA) for satellite communications using a decoupling structure is proposed. Good isolation between transmit and receive ports is achieved by placing two identical linearly polarized resonators orthogonal to each other. Each resonator consists of a main rectangular dielectric resonator of the dielectric constant of 10 and is loaded by a thin dielectric slab of lower permittivity of 5 to broaden the matching bandwidth further. The isolation is further improved by loading an absorber and etching several slots in the ground plane. Finally, the proposed DRA is fabricated and measured to validate the concepts. Measurement results show high isolation of more than 50 dB over the desired operating bandwidth from 23.04 GHz to 24.08 GHz (ka-band) with a peak gain of about 8.93 dBi and 8.09 dBi for Port 1 and Port 2, respectively. In addition, the proposed IBFD DRA provides 11.87 GHz and 4.84 GHz isolation bandwidths over 25 dB and 30 dB, respectively, making it a potential candidate for mm-wave terrestrial applications.

Dual-UWB Dielectric Resonator Antenna for OAM Communication

Dual-UWB Dielectric Resonator Antenna for OAM Communication

Wideband Substrate Integrated Cavity-Backed Dielectric Resonator Antenna at Sub-6-GHz Band

The design and implementation of a wideband single-mode dielectric resonator antenna (DRA) with a substrate integrated cavity-backed structure is presented in this paper. Two short-circuited striplines with differential feeding are placed inside the substrate integrated cavity (SIC) for pure mode excitation of the DRA, providing stable radiation characteristics, and low cross polarization levels. The cavity is coupled to the cylindrical DRA through an annular slot. The fundamental <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mathrm{ HEM}}_{11\delta }$ </tex-math></inline-formula> mode of the DRA is excited over a wide frequency band, as a result of the similar field distribution created on the coupling annular slot by two modes inside the cavity. Measurement results show a maximum gain of 8.2 dBi at 5.45 GHz. The gain is 7.8 dBi at the center frequency of 5.15 GHz and its 1-dB bandwidth is 23%. The measured 10-dB return loss bandwidth is 26% (centered at 5.15 GHz) which is the highest among the previously reported works based on cavity-backed DRAs and single-mode excited DRAs. The measured co-polarization and cross-polarization gain difference at the boresight direction is more than 26 dB. This antenna element can be used to cover a wide range of wireless standards in wireless access point and applications due to its stable wide band performance.

A 3D-Printed Encapsulated Dual Wide-Band Dielectric Resonator Antenna With Beam Switching Capability

A 3D-Printed Encapsulated Dual Wide-Band Dielectric Resonator Antenna With Beam Switching Capability

Two-port Silicon-based MIMO Nano-dielectric Resonator Antenna with Polarization Diversity for Photonics Applications

Two-port Silicon-based MIMO Nano-dielectric Resonator Antenna with Polarization Diversity for Photonics Applications

5G MILLIMETER WAVE MIMO DIELECTRIC RESONATOR ANTENNA

A four-element rectangular dielectric resonator antenna (DRA) array for fifth generation (5G) multiple-input-multiple-output (MIMO) application at 28 GHz is presented. Each DRA element of the array has a very small dimension of 3 &amp;times; 0.03 &amp;times; 6 mm and oriented at an angle of 90 deg to each other. Total dimension of the proposed antenna system is 20 &amp;times; 20 &amp;times; 7 mm. Each antenna of the system has high radiation efficiency (&amp;#60; -0.004 dB). Defected ground structure is used to obtain very good isolation (&amp;#62; 27 dB) between any two DRA elements of the array. Moderate directivity (&amp;#62; 4.1 dBi) of the MIMO antenna can be increased up to 7.8 dBi using thin metal walls to separate each DRA element of the system. This MIMO antenna system is capable of giving 4 GHz impedance band width extending from 25.78 to 29.78 GHz. Computer simulation technology is used to design and investigate the performance parameters of this MIMO antenna system. Performance parameters of the proposed antenna are compared with similar types of antennas found in recent literature.

Communication Compact Dual-Band Hybrid Dielectric Resonator Antenna for 5G Millimeter-Wave Applications

In this communication, a new kind of dual-band hybrid dielectric resonator antenna (DRA) with its array design and extended dual-polarized version is presented for fifth generation (5G) millimeter-wave (mm-Wave) applications. The hybrid antenna that integrates three types of resonators of strip, slot, and DRA can generate four resonances in 28 and 39 GHz frequency bands. In this design, the strip and slot modes are used to cover the lower frequency band of 26.41–30.42 GHz, while the TE111 and TE131 modes of the DRA are employed to cover the upper frequency band of 36.05–40.88 GHz. It shows that the 5G mm-Wave bands of n257 and n260 can be covered simultaneously. It should be mentioned that our proposed hybrid antenna has a compact size of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.34\lambda _{01} \times 0.36\lambda _{01} \times 0.1\lambda _{01}$ </tex-math></inline-formula> ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda _{01}$ </tex-math></inline-formula> means the free-space wavelength at 28 GHz). Based on the compact size of the antenna element, a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1 \times $ </tex-math></inline-formula> 5 antenna array with the capability of beam steering is designed and simulated. Wide steering angles of ±50° and ±40° can be obtained at 28 and 39 GHz frequency bands, respectively. Furthermore, an extended dual-polarized antenna configuration is also described and measured that provides similar two-port impedance and radiation performance with the single-port counterpart.

Additive Manufacturing of Linear Continuous Permittivity Profiles and Their Application to Cylindrical Dielectric Resonator Antennas

The utilization of additive manufacturing (AM) to engineer the permittivity profile of dielectric resonator antennas (DRAs) is considered. For the first time, the capabilities of AM are exploited to create continuously swept permittivity profiles and applied to cylindrical DRAs. The spatial variant lattices (SVL) synthesis algorithm is implemented to create the desired permittivity profiles from a single material, and resulting geometries are manufactured using a high-permittivity material in a fused deposition modeling AM process. Three individual antennas for global navigation satellite system bands are designed and manufactured, two inhomogeneous DRAs with continuous permittivity profiles along the radial and vertical axis, and one homogeneous DRA for comparison. The manufactured antennas are characterized by impedance, realized gain, and axial ratio. Experimental results agree well with simulations and show increased impedance-, gain-, and axial-ratio bandwidths for both inhomogeneous antennas compared to the homogeneous one.