Search Results (61)

Traditional Beidou Navigation Satellite System anti-jamming array antennas mostly use PCB plates, but in extreme vibration environments, their rigidity may cause the antenna structure to be more susceptible to damage. Especially in an extremely high-temperature environment, it may cause thermal expansion, softening, and even melting of metal materials, which will affect the structure and performance of the antenna; In this paper, a Beidou array antenna integrating high seismic resistance, high-temperature stability, and anti-interference ability is designed and studied. The structural parts of the antenna are composed of 7075 aluminum alloy and high-temperature ceramic material technology, which has a compact structure and strong corrosion resistance, which is especially suitable for aviation and marine environments. The antenna works stably at 400 °C and has excellent heat resistance. Built-in shock-absorbing elements or shock-absorbing materials are used to effectively absorb and disperse vibration energy and reduce the direct impact on the internal components of the antenna. Considering the anti-interference performance caused by the size of the array spacing and the mutual coupling between the array elements, the array spacing is designed to be between λ/4 and λ/2. In simulations and experiments, the designed antenna array shows good performance and proves its applicability for high-temperature applications. The antenna frequency includes the B3 band (1250.618~1286.423 MHz) and B1 band (1559.052~1591.788 MHz) of the Beidou Navigation Satellite System. The following article includes the introduction, proposed array antenna structure and dimension, antenna simulation results, antenna protype and environment test, conclusions and future work. Full article

A wideband dual-polarized dielectric resonator antenna (DRA) with gain-filtering response was proposed in this paper. First, a differentially fed, low-profile crossed-DRA was used to obtain orthogonal polarizations with two resonant modes. A radiation null at upper band edge was also generalized. Second, with the introduction of four parasitic patches at the top of the crossed DRA, another resonant mode at lower band was excited, and the bandwidth was greatly expanded. Moreover, the introduction of parasitic patches could also help improve the selectivity of realized gain with another radiation null at the upper band edge. Furthermore, four sequentially rotated shorting coupling structures (SRSCSs) were proposed for the first time to generalize two additional radiation nulls. Finally, a wideband bandpass filtering response of the realized gain with four radiation nulls was obtained. Prototypes of the proposed antennas were fabricated, and the testing results showed that the antenna had a wide operation band of 57.1% from 2.75 GHz to 4.95 GHz with sharp roll-off at the band edge. This technique could also be used in wireless communication devices at millimeter/optical front ends and other multi-wavelength fiber lasers with micro structures. Full article

This paper presents a novel dual-band antenna design for simultaneous 5G communication and localization services in high-speed train (HST) scenarios. It operates in the frequency range 1 (FR1) n78 band at 3.5 GHz and the FR2 n258 band at 26.2 GHz. The design combines a dielectric resonator antenna (DRA) and a planar patch antenna to achieve dual-band functionality. This provides efficient performance across both mid-band and millimeter-wave frequencies for advanced 5G applications. The dual-band configuration is motivated by the need to balance wide coverage and high data rates within a single, compact antenna design, addressing the specific challenges of maintaining stable connectivity and efficient spectrum utilization in high-speed, data-intensive environments. A common challenge in dual-band antenna designs is the interference between low- and high-frequency antennas, which can significantly degrade performance or even cause antenna failure. Our design addresses this issue by minimizing interference between the patch and DRA elements, ensuring stable operation across both frequency bands. As a result, the antenna achieves impressive gains and bandwidth, with a maximum gain of 6.8 dBi and an impedance bandwidth of 22.5% for the dual-band configuration. Also, both radiators present high total efficiency above 90%. The compact size of the antenna makes it highly suitable to be mounted on the roof of the train to enable 5G communication and location-based services for both safety-critical and liability-critical applications in HST scenarios. Full article

A pattern-reconfigurable, vertically polarized (VP), electrically small (ES), Huygens source antenna (HSA) is demonstrated. A custom-designed reconfigurable inverted-F structure is embedded in a hollowed-out cylindrical dielectric resonator (DR). It radiates VP electric dipole fields that excite the DR’s HEM_11δ mode, which in turn acts as an orthogonal magnetic dipole radiator. The HSA’s unidirectional properties are thus formed. It becomes low-profile and electrically small through a significant lowering of its operational frequency band by loading the DR’s top surface with a metallic disk. The entire 360° azimuth range is covered by each of the HSA’s four 90° reconfigurable states, emitting a unidirectional wide beam. A prototype was fabricated and tested. The measured results, which are in good agreement with their simulated values, demonstrate that the developed wideband Huygens source antenna, with its 0.085 λ_L low profile and its 0.20 λ_L × 0.20 λ_L compact transverse dimensions, hence, electrically small size with ka = 0.89, exhibits a wide 14.1% fractional impedance bandwidth and a 6.1 dBi peak realized gain in all four of its pattern-reconfigurable states. Full article

This article presents a circular polarized enclosed dielectric resonator antenna (DRA), operating at 5.8 GHz. The design consists of a twist DRA, which is enclosed in a box to give stability to the structure. The circular polarization of the antenna depends on the sense of twisting the top with respect to its base to achieve Left Hand Circular Polarization (LHCP) or Right Hand Circular Polarization (RHCP). The antenna was manufactured using 3D printing and low-loss dielectric filament. The measurement results show the two resonance frequencies and an axial ratio below 3 dB at the operational frequency, while exhibiting a bandwidth and gain compatible for unmanned aerial vehicle (UAV) applications. Full article

This paper presents a hybrid dielectric resonator antenna (HDRA) for circularly polarized (CP) radiation at 5 GHz, designed for WLAN applications. The antenna features a single probe feed that excites a combination of a circular ring patch and a cylindrical dielectric resonator (DR) element, achieving stable gain across a wide bandwidth. The parametric analysis and vector E-field distribution of the proposed antenna presents the optimization, and it is evidence of CP radiation, respectively. The hybrid DRA has a reflection loss (RL) bandwidth of 485 MHz, from 4740 to 5225 MHz, and an axial ratio (AR) bandwidth of 150 MHz, ranging from 4950 to 5100 MHz. It achieves a peak gain of 7.03 dBic at 5 GHz, making it suitable for missile tracking, data link communications, and IEEE 802.11n WLAN systems. Measurements of a prototype in an anechoic chamber show a close match with simulation results. Full article

In this paper, a novel dual-slot-fed dielectric resonator antenna (DRA) with rectangular and irregular elements, designed for 5G wireless applications, is presented. The DRA achieves wideband capability by combining the resonant modes of the rectangular and irregular DRA elements, which is a less common feature in conventional designs. A frequency ratio adjustment technique, based on the concept of inductive de-loading, is uniquely proposed for the independent frequency adjustment of the irregular DRA. Unlike traditional methods, an equivalent circuit presentation was developed to interpret the impedance characteristics of single-element DRAs, and to provide new insights into the presence of inductive de-loading from a circuit perspective. For verification, a dual-slot-fed prototype was fabricated through digital light processing (DLP)-based 3D printing technology, with the aim of customizable design and low-cost fabrication. The measured and simulated results of reflection coefficients and radiation patterns showed good agreements, with a measured bandwidth of 51.6% (2.96–5.02 GHz), effectively covering the desired 5G n77–n79 (3.3–5.0 GHz) frequency bands. Full article

This paper explores the potential use of fused deposition modeling (FDM) technology for manufacturing microwave and millimeter-wave dielectric resonator antennas (DRAs) for 5G and beyond communication systems. DRAs operating at microwave and millimeter-wave (mmWave) frequency bands were simulated, fabricated, and analyzed in terms of manufacturing quality and radio frequency (RF) performance. Samples were manufactured using a 3D printer and PREPERM^® ABS1000 filament, which offers a stable dielectric constant (${\epsilon }_r$ = 10 ± 0.35) and low losses (tan $\delta$ = 0.003) over wide frequency and temperature ranges. Surface profile tests and microscope measurements revealed discrepancies in the dimensions in the xy-plane and along the z-axis, consistent with the observed shift in resonant frequency. Despite these variations, reasonably good agreement between RF-simulated and measured results was achieved, and the DRA array successfully covered the intended mmWave band. However, challenges in achieving high precision may restrict applications at higher mmWave bands. Nevertheless, compared with conventional methods, FDM techniques offer a highly accessible and flexible solution with a wide range of materials for home and micro-manufacturing of mmWave DRAs for modern 5G systems. Full article

A wideband dual-beam dielectric resonator antenna (DRA) with substrate integration capability was proposed for millimeter-wave (mm-wave) applications. The four rows of air vias along the x-direction and two extended rectangular patches could shift the undesirable radiation mode upward and move the conical-beam radiation mode downward, respectively. Thus, the TE₂₁₁ mode and the TE₄₁₁ mode of the patch-loaded perforated rectangular substrate integrated dielectric resonator (SIDR) supporting the dual-beam radiation can be retained in the operating band, and their radiation can be improved by the air vias along the y-direction. The T-shaped line coupled dual-slot structure could excite the above two modes, and a dual-slot mode supporting dual-beam radiation could also work. Then, a wideband DRA with a stable dual-beam radiation angle can be achieved, and its impedance matching can be improved by two air slots on two sides. Compared with the state-of-the-art dual-beam antennas, the proposed antenna shows a wider bandwidth, a higher radiation efficiency, and the substrate integration capability of DRA, making it more suitable for mm-wave applications. For demonstration, a 1 × 4 array was designed with the 10 dB impedance matching bandwidth of 41.2% and the directions of the dual beams between ±30° and ±35°. Full article

This paper introduces an innovative and cost-effective approach for developing a millimeter-wave (mmWave) frequency-reconfigurable dielectric resonator antenna (DRA), which has not been reported before. The antenna integrates two rectangular DRA elements, where each DRA is centrally fed via a slot. A strategically positioned PIN diode is employed to exert control over performance by modulating the ON–OFF states of the diode, thereby simplifying the design process and reducing losses. In the OFF state, the first DRA, RDRA-I, exclusively supports the TE₃₁₁ resonance mode at 24.3 GHz, offering a 2.66% impedance bandwidth and achieving a maximum broadside gain of 9.2 dBi. Conversely, in the ON state, RDRA-I and RDRA-II concurrently operate in the TE₅₁₃ resonance mode at 29.3 GHz, providing a 2.7% impedance bandwidth and yielding a high gain of up to 11.8 dBi. Experimental results substantiate that the proposed antenna presents an attractive solution for applications necessitating frequency-reconfigurable and high-performance mmWave antennas in 5G and Beyond 5G (B5G) communication systems. Full article

This paper presents the design of a two-port dual-band dual-circularly-polarized dielectric resonator antenna (DRA). The proposed DRA is formed by stacking two dielectric resonators (DRs) of different shapes, including a hexagonal DR on top and a cross-shaped DR on the bottom. It is designed to resonate at two near-degenerate orthogonal modes of TE₁₁₁ and TE₁₁₃, and an aperture-coupled feeding through a cross-like slot is used to achieve dual-band impedance matching simultaneously for right- and left-handed circular polarizations. Tests were conducted on a prototype working in C-band to verify the design concept. The experiment results demonstrate that the proposed DRA has exceptional performance with measured −10 dB reflection bandwidths of 24.4% and 17.4%, 3 dB axial ratio bandwidths of 21.2% and 16.3%, and maximum gains of 5.64 and 8.13 dBic for the lower and upper bands, respectively. Moreover, the measured channel isolation is more than 15.8 dB. The results obtained from the experiments show good agreement with the simulation, and hence, it can be concluded that the proposed DRA is a promising solution that can be used for various wireless communication applications. Full article

This paper presents a novel wideband circularly polarized millimeter-wave (mmWave) hemispherical dielectric resonator antenna (HDRA). Two distinct configurations of alumina dielectric resonator antennas (DRAs) are investigated, each featuring a different coating: the first configuration incorporates a polyimide layer, while the second involves a perforated alumina. Both configurations demonstrate promising characteristics, including impedance and axial ratio (AR) bandwidths of 58% and 17.7%, respectively, alongside a maximum gain of 10 dBic at 28 GHz. Leveraging additive manufacturing technology, the HDRA with the perforated coating layer is fabricated, simplifying assembly and eliminating potential air gaps between layers, thereby enhancing the overall performance. This innovative approach yields a circularly polarized (CP) HDRA suitable for Beyond 5G (B5G) communication systems. Agreement between measurements and simulations validates the efficacy of the proposed design, affirming its potential in practical applications. Full article

This article delves into the capabilities of 3D-printed millimeter-wave (mmWave) layered cylindrical dielectric resonator antennas (CDRAs). The proposed design yielded promising results, boasting a remarkable 53% impedance bandwidth spanning the frequency spectrum from 18 to 34 GHz. Furthermore, the axial ratio (AR) bandwidth achieved an impressive 17%, coupled with a maximum gain of 13.3 dBic. These notable results underscore the efficacy of the proposed design, positioning it as a viable solution for applications in Beyond 5G (B5G). A novel assembly technique was also investigated, employing additive manufacturing to seamlessly merge two layers with distinct dielectric constants into a singular layer. This innovative approach systematically eliminates the potential for air gaps between layers, enhancing the antenna’s overall performance. This approach exhibited potential, particularly in the performance of a millimeter-wave circularly polarized (CP) cylindrical DRA featuring a perforated coating layer. The synergy between measurements and simulations demonstrates a remarkable alignment, providing robust validation of the effectiveness of the proposed design. Full article

We review dielectric resonator antenna (DRA) designs. This review examines recent advancements across several categories, specifically focusing on their applicability in array configurations for millimeter-wave (mmW) bands, particularly in the context of 5G and beyond 5G applications. Notably, the off-chip DRA designs, including in-substrate and compact DRAs, have gained prominence in recent years. This surge in popularity can be attributed to the rapid development of cost-effective multilayer laminate manufacturing techniques, such as printed circuit boards (PCBs) and low-temperature co-fired ceramic (LTCC). Furthermore, there is a growing demand for DRAs with beam-steering, dual-band functions, and on-chip alignment availability, as they offer versatile alternatives to traditional lossy printed antennas. DRAs exhibit distinct advantages of lower conductive losses and greater flexibility in shapes and materials. We discuss and compare the performances of different DRA designs, considering their material usage, manufacturing feasibility, overall performance, and applications. By exploring the pros and cons of these diverse DRA designs, this review provides valuable insights for researchers in the field. Full article

A circularly polarized (CP) multiple-input multiple-output (MIMO) dielectric resonator antenna (DRA) is presented in this paper for 5G millimeter-wave (mm-wave) applications. This MIMO antenna consists of two high-order mode CP DRAs, which use the modified cross slots to generate the CP fields. Two complementary split ring resonators (CSRR) are used to isolate the surface current on the metal ground, which can increase the antenna isolation and optimize the axial ratio when each port is excited. The proposed MIMO antenna obtains a simulated impedance bandwidth from 25.41 to 31.18 GHz and an axial ratio (AR) bandwidth (AR < 3 dB) from 25.49 to 29.52 GHz for the 5th generation wireless communication applications. The measured results show that the antenna covers the overlapped bandwidth of 11% and isolation less than −25 dB over the frequency band range. The measured average (peak) gain is 5.84 (6.24) dBic at 26.5 GHz to 29.5 GHz for port 1 and 6.90 (7.27) dBic for port 2. Full article