Millimeter-wave Antenna Research Articles

Miniaturized Multi-band Millimeter-Wave Vivaldi Antenna with Performance Optimization at 28 GHz for 5G MIMO Applications

A novel design for Vivaldi antenna is introduced to operate in more than one frequency band in the millimeter-wave spectrum range with high gain. The proposed Vivaldi antenna is planar and printed on both sides of Rogers 3003C flexible substrate. A parasitic annular ring is added to each arm of the Vivaldi antenna to adjust the impedance matching and maximize the gain. The dimensions of the antenna are optimized using the CST microwave simulator to obtain the best impedance matching bandwidths and highest gain in a compact-size antenna. The 28-GHz band is then selected due to its importance to enhance the gain and improve the operating bandwidth for the 5G applications. A gain of 10 dBi and bandwidth of 6.1 GHz are obtained at 28 GHz. A multiple-input multiple-output (MIMO) antenna system is then designed for pattern diversity for the fifth-generation mobile applications. The performance of the MIMO system is evaluated regarding the envelope correlation coefficient and the diversity gain showing good results. The optimized antenna is fabricated and its return loss and radiation patterns are measured showing good consent between the simulations and the practical work. The MIMO antenna system is also fabricated, and its performance is measured regarding the reflection and coupling coefficients showing good agreement between the measurements and simulations.

Dodecahedron lattice of rattling phenomenon, and microwave dielectric properties of yttrium aluminum garnet ceramics and its application verification for Wifi6E/7 patch and 6G resonant antennas

In garnet phase ceramics Y2.9M0.1Al4.9Si0.1O12 (M = Mg2+, Co2+, Zn2+, Mn2+, Ca2+, Sr2+, Ba2+), rattling effects occur when M = Mg2+, Co2+, Zn2+, Mn2+ ions with smaller ionic radius (<1Å) occupy the dodecahedron lattice lattices. This results in an abnormally high dielectric constant, in contrast to the larger ionic radius (>1 Å) of M = Ca2+, Sr2+ and Ba2+, which deviate from the theoretical values calculated using the Clausius-Mosotti formula according to each ion’s polarizability. The optimal microwave dielectric properties for Y2.9Mg0.1Al4.9Si0.1O12 was obtained by sintering at 1575 °C for 5 h (Q×f = 51,382 GHz, εr = 9.74, and τf = −30.12 ppm/°C). Additionally, a thermal stable Y2.9Mg0.1Al4.9Si0.1O12-6 wt%TiO2 composite ceramic was developed. Based on this composite, a Wifi6E/7 patch antenna operating at 6.3 GHz and a millimeter-wave resonant antenna functioning at 27.1 GHz were designed and validated. This indicates the potential application prospects of garnet ceramics in 5G/6G radio communication technologies.

Hybrid Integration of 5G/B5G Millimeter-wave and Microwave Antennas in Handsets for ISAC

Hybrid Integration of 5G/B5G Millimeter-wave and Microwave Antennas in Handsets for ISAC

Millimeter-Wave Beam-Tilted Phased Array Antenna for 5G-Enabled IoT Devices

Millimeter-Wave Beam-Tilted Phased Array Antenna for 5G-Enabled IoT Devices

Millimeter-Wave Dual-mode Low Divergence Angle OAM Antennas with High Mode Purity in Wide Bandwidth

Millimeter-Wave Dual-mode Low Divergence Angle OAM Antennas with High Mode Purity in Wide Bandwidth

3D Printed High-Gain Millimeter-Wave Horn Antenna with a Hybrid Metal and Dielectric Lens

3D Printed High-Gain Millimeter-Wave Horn Antenna with a Hybrid Metal and Dielectric Lens

Millimeter-wave End-Fire Magneto-Electric Dipole Antenna and Array with Horizontal Polarization and Wide Bandwidth

Millimeter-wave End-Fire Magneto-Electric Dipole Antenna and Array with Horizontal Polarization and Wide Bandwidth

A Triple-Band Triple-Polarization End-fire/Broadside Millimeter-Wave Phased Array Cavity Antenna with Small Frequency Ratio

A Triple-Band Triple-Polarization End-fire/Broadside Millimeter-Wave Phased Array Cavity Antenna with Small Frequency Ratio

Millimeter-Wave Wideband Wide-angle Scanning Linear Phased Array Antenna Using Pin-loaded Slot Elements

Millimeter-Wave Wideband Wide-angle Scanning Linear Phased Array Antenna Using Pin-loaded Slot Elements

Retracted: Research on Quantization Error Influence of Millimeter-Wave Phased Array Antenna

Retracted: Research on Quantization Error Influence of Millimeter-Wave Phased Array Antenna

A Millimeter-Wave Wideband Antenna Module With Switchable Fan-Beam Radiation for Wide Coverage of 5G IoT Applications

Millimeter wave (mm-wave) antenna modules with switchable beam radiation provide a potential solution for enabling flexible wireless links and high data rate in Internet of Things (IoT) networks. Aiming to simultaneously fulfill a wide coverage and follow the cost-effective principle of IoT devices, a novel mm-wave wideband antenna module with switchable fanbeam radiation is proposed based on an air-filled planar Cassegrain beam-former. A comprehensive design procedure combing the theoretical calculation and differential evolution (DE) algorithm is first introduced to construct the beam-former with wide-angle scanning capability. The desirable apertureshared switchable fan-beam radiation with high crossover is then obtained with the aid of a proposed two-feed-per-beam (2FPB) scheme based on a low-loss integrated switch network. A prototype of the antenna in the Ka-band is fabricated by simultaneously adopting the metallic three-dimensional (3D) printing and printed circuit board (PCB) technology. Excellent operating characteristics, including a wide bandwidth of more than 32%, twenty stable fan-shaped radiation beams scanning over a wide angular range of ±45∘ in the H-plane, a high beam crossover of about -3 dB, a gain of up to 19.6 dBi, and a radiation efficiency of greater than 80% are demonstrated experimentally. With the ability to fulfill the radio coverage within a wide conical area, the presented antenna module would be an attractive candidate for the fifth generation (5G) IoT applications.

Directive Millimeter-Wave End-Fire Diplexing Antenna for IoT Applications

Millions of passengers use High-speed trains (HSTs) daily, in the world. The roofs of HSTs can be equipped with a variety of transmitting and receiving antennas to accommodate high-data-rate Internet services with reliable radio access for passengers. The design of commercial antenna systems is a compromise between cost, size, manufacturability, and performance. This paper proposes a new, compact and low-cost two-port millimeter-wave diplexing directive end-fire antenna, which is designed, fabricated and tested. The proposed antenna is made of a tapered slot antenna and a diplexing structure based on transitions in stacked Printed Circuit Boards (PCBs). The ports of the antenna cover the frequency band 25.9-32.4 GHz (6.5 GHz) and 34.6-37.1 GHz (2.5 GHz). In all operating frequency bands, measured isolation between input ports exceeds 24 dB. Furthermore, symmetric directive end-fire radiation patterns are obtained experimentally, with low side lobe level and low front-to-back ratio. All these features make the proposed diplexing antenna suitable for high-speed railway wireless networks.

Millimeter-Wave and Short-Range Wireless Communication Antenna Based on High-Conductivity Graphene-Assembled Film.

Millimeter-wave and short-range wireless communication is an important part of the Internet of Things due to its advantages of high transmission speed and large data capacity. In this paper, two antenna arrays operating at typical millimeter-wave bands (45 and 60 GHz) based on graphene-assembled films (GAF) are proposed for short-range wireless communication application. The 45 GHz graphene-assembled film antenna array is in the form of a magnetoelectric dipole antenna with a strip slot coupling to achieve bidirectional radiation, which offers an operating bandwidth of 40-49.5 GHz with a realized gain of 11.8 dBi. The 60 GHz graphene-assembled film antenna utilizes a microstrip discontinuous radiation array to achieve radiation with an operating bandwidth of 59-64 GHz, reaching the peak realized gain of 14.92 dBi over the working frequency. Finally, we proposed an experimental validation to verify the transmission performance of both antenna arrays in an actual conference room. The results show that the signal drops slowly in the room with drop rates of 0.064 dB/cm (at 45 GHz) and 0.071 dB/cm (at 60 GHz), while it steeply dropped through the wall with the drop rates of 2.3 and 3.13 dB/cm, more than 35-fold difference in signal drop rates in the room and through the wall. It has been confirmed that the proposed antenna arrays can successfully realize fast indoor short-range wireless communication while also preventing signal leakage through walls, thereby enhancing the security of information. In summary, this is the first time that we have applied graphene-based materials to millimeter-wave and short-range wireless communications, revealing the significant potential of carbon-based materials in high-frequency communication systems.

A millimeter-wave beamforming antenna array with mutual coupling reduction using metamaterial surface

A millimeter-wave beamforming antenna array with mutual coupling reduction using metamaterial surface

40-GHz Band Photodiode-Integrated Phased Array Antenna Module for Analog-Radio over Fiber toward Beyond 5G

In 5th generation (5G) and Beyond 5G mobile communication systems, it is expected that numerous antennas will be densely deployed to realize ultra-broadband communication and uniform coverage. However, as the number of antennas increases, total power consumption of all antennas will also increase, which leads to a negative impact on the environment and operating costs of telecommunication operators. Thus, it is necessary to simplify an antenna structure to suppress the power consumption of each antenna. On the other hand, as a way to realize ultra-broadband communication, millimeter waves will be utilized because they can transmit signals with a broader bandwidth than lower frequencies. However, since millimeter waves have a large propagation loss, a propagation distance is shorter than that of low frequencies. Therefore, in order to extend the propagation distance, it is necessary to increase an equivalent isotropic radiated power by beamforming with phased array antenna. In this paper, a phased antenna array module in combined with analog radio over fiber (A-RoF) technology for 40-GHz millimeter wave is developed and evaluated for the first time. An 8×8 phased array antenna for 40-GHz millimeter wave with integrated photodiodes and RF chains has been developed, and end-to-end transmission experiment including 20 km A-RoF transmission and 3-m over-the-air transmission from the developed phased array antenna has been conducted. The results showed that the 40-GHz RF signal after the end-to-end transmission satisfied the criteria of 3GPP signal quality requirements within ±50 degrees of main beam direction.

Ultra-low temperature sintered (1–x)BaV2O6-xLiF ceramics for ULTCC and 5 G millimeter-wave antenna applications

Ultra-low temperature sintered (1–x)BaV2O6-xLiF ceramics for ULTCC and 5 G millimeter-wave antenna applications

Joint Microwave and Millimeter-Wave Antenna Design for UAV-Enabled Communications

Wireless communications aided by unmanned aerial vehicles (UAVs) have emerged as a promising technology for serving numerous terminal devices of the Internet of Things (IoT). To support such a broad range of emerging applications, millimeter-wave (mm-Wave) is an effective solution because it has the characteristics of high transmission efficiency, wide frequency band, and very low latency. Meanwhile, a UAV-assisted communication system also requires a global positioning system (GPS) reception (1.575 GHz) and ground control unit (2.4 GHz). This paper investigates a highly integrated multi-band antenna design to operate at the microwave (μ-Wave) and mm-Wave bands for robust and flexible UAV communications. Each antenna operating band utilizes the technology of a substrate-integrated waveguide (SIW) cavity-backed antenna. By strategically engineering an mm-Wave antenna into a 2.4 GHz band antenna to share the aperture, besides showing high aperture reuse efficiency with a large frequency ratio, the proposed antenna has also maintained the geometrical advantages of compactness, planar configuration, and ease of integration with other circuits. Furthermore, the proposed antenna can provide flexible radiation patterns with upper/lower-space signal coverage according to the mission demands of the UAV. Experimental results of the prototype show that the antenna can fully cover the 1.575 GHz, 2.4 GHz, and fifth-generation (5G) mm-Wave bands of n257, n258, and n261. Multiple bands and stable radiation characteristics indicate the proposed antenna's suitability for deploying a UAV-supported wireless network.

Wideband Millimeter-Wave MIMO Antenna with a Loaded Dielectric Cover for High-Gain Broadside Radiation

In a millimeter-wave terminal device, the use of a radome degrades the radiating performance of the broadside antenna, especially for the MIMO antenna system. In this study, a dielectric cover is de-signed and investigated to enhance the broadside gain of a millimeter-wave MIMO antenna, while keeping its wideband and high isolation performance. Firstly, a compact wideband ladder-shaped slot antenna is proposed with 21.9% bandwidth. The effectiveness of the dielectric cover design criteria over the wideband antenna is investigated. Then, this wideband antenna element is expanded to a 2 × 2 MIMO antenna by forming a center-symmetric structure and isolating it via the inserted metal vias. By loading the dielectric cover, this millimeter-wave MIMO antenna is verified with enhanced broadside gain for more than 2.1 dB. With the measured impedance bandwidth of 21.9% (57.0–71.0 GHz), peak broadside gain of 12.3 dBi, and high isolation over 15 dB, the proposed MIMO antenna is suitable for wireless gigabit terminal devices.

Quasi-binomial series-fed array for performance improvement of millimeter-wave antenna for 5G MIMO applications

A quad-port MIMO antenna based on a quasi-binomial series-fed array is presented in this paper for n257 and n258 millimeter-wave applications with an investigation of additional loaded patches on performance enhancement of the conventional binomial series-fed array. The single element of the proposed MIMO is a 3 × 3 element planar binomial series-fed array whose width of the radiating elements is tapered to achieve the binomial distribution. From both simulated and tested results, it is observed that a wider bandwidth (S11 < –10 dB of 21.78 %), high peak gain (12.4 dBi), and high radiation efficiency (92 %) with side lobe level (SLL) reduction of more than 9 dB are achieved by additional loaded patches. This design approach does not only offer wider bandwidth, low SLL, and gain increment, but also ensures the excellent diversity performances of the very closely spaced (0.116λ) MIMO antenna, without utilizing any additional decoupling structure. The proposed MIMO antenna system offers impedance bandwidth (S11 < − 10 dB) from 24.6 GHz to 30.59 GHz, isolation > 27 dB, envelope correlation coefficient < 0.0002, diversity gain > 9.99 dB, and mean effective gain between –4 dB and –8 dB. Owing to its performance attributes, the proposed antenna is an excellent choice for 5G millimeter-wave communication devices, including but not limited to enormous IoT, smart cities, and virtual reality.

Millimeter-Wave Substrate-Integrated Corrugation-Loaded H-Plane Horn Antenna With Beamwidth and Back Radiation Suppression

Millimeter-Wave Substrate-Integrated Corrugation-Loaded H-Plane Horn Antenna With Beamwidth and Back Radiation Suppression