Millimeter-wave Wireless Applications Research Articles

A novel SW-ESIW slot antenna and its applications in millimeter-wave array design

A novel structure of slot antenna with high gain and compact size for millimeter-wave (mmW) applications is proposed. This is the first attempt to apply slow-wave substrate integrated waveguide (SW-ESIW) to the field of antennas and their arrays. Two slot antenna arrays were designed, fabricated and measured. The measured results are in agreement with the simulation. The removal of dielectric substrate improves the radiation gain. At the same time, the slow wave effect, by means of physical separation of electric and magnetic fields, decreases both the lateral and longitudinal dimensions of the antenna. The SW-ESIW slot antenna can achieve miniaturization while retaining the advantages of high gain of ESIW. The 1 × 4-slot array shows a measured −10 dB bandwidth of 16% (30.5–35.8 GHz) with a measured maximum gain of 11.69 dB. The 4 × 4-slot array achieves a measured −10 dB bandwidth of 7.6% from 31.6 to 34.1 GHz with a measured peak gain of 18.75 dB. In addition, during the operating band, the radiation pattern is stable. Compared with the previously structures, the proposed SW-ESIW antenna structure has a better trade-off between gain and footprint. It can be flexibly adjusted to adapt to different requirements. These performances ensure that the antenna array based on the proposed structure is a promising candidate for millimeter-wave wireless applications including the fifth-generation mobile communications.

Differentially Fed, 1-D Phased-Array Antenna-on-Display Featuring Wideband and Polarization Agility for Millimeter-Wave Wireless Applications

Differentially Fed, 1-D Phased-Array Antenna-on-Display Featuring Wideband and Polarization Agility for Millimeter-Wave Wireless Applications

Design and Fabrication of A Dielectric Antenna for Millimeter-Wave Wireless Applications.

Design and Fabrication of A Dielectric Antenna for Millimeter-Wave Wireless Applications.

Design and simulation of a novel miniaturized printed antenna with ultra-wideband and high gain for millimeter-wave wireless applications

The goal of this work is to create a new patch antenna array with a standard gain, broadband, unidirectional radiation pattern, and high efficiency, making it a viable contender for millimeter-wave wireless applications. This study begins with a simple single-patch antenna that has four key components to provide effective matching and a wide impedance bandwidth: elliptical lateral edges, vertical stubs, slots expressed in concavity, and notches. The ground plane was defect-free, and the patch was printed on a Rogers RT5880 substrate. The performance of the proposed antenna can be improved using array topologies of 1×2 and 2×2 patches, for which a corporate feed network was built for excitation. The suggested 2×2 array antenna with a compact size of 18x16.1 mm2 achieved a gain of 13.8 dB, 92% efficiency, a return loss of-34.8 dB, and an ultra-wide bandwidth of 12.2 GHz (ranging from 39.9 to 52.1GHz) at a resonant frequency of 43.2. It’s a novel compact 2×2 array antenna appropriate for miniature devices is suggested using CST studio software, which gathers all qualities together, including high-gain, radiation efficiency, and ultra-wideband. The planned antenna operating frequency range runs from 27 to 58 GHz, which encompasses multiple frequency bands, such as V, Q, and Ka.

A New CPW-Fed Semicircular Inverted Triangular Shaped Antenna Based on Mixed-Alternate Approach for 5G Millimeter-Wave Wireless Applications.

This paper presents the design and development of a new semicircular inverted triangular shaped antenna for 5G millimeter-wave wireless applications. An alternate-mixed approach based on cavity, slots and loaded stubs is employed in the designed antenna lattice. The suggested antenna structure is formed by a radiator, partial defected metal ground plane and a 50 Ω coplanar waveguide. The proposed antenna resonated at multiple frequencies by the setting up of the proper dimensions and locations of the rectangles, elliptical cut slots and cavity stubs. Furthermore, a parametric analysis is carried out to examine the antenna's effectiveness and impedance-matching controls. The proposed structure is realized on the low-cost RT/Duroid Rogers RO3010™ laminate with an overall small size of 1.381λ0 × 1.08λ0 × 0.098λ0, where λ0 represents the wavelength corresponding to the minimum edge frequency of the 23 GHz at 10 dB impedance bandwidth of the antenna. The antenna's key characteristics in terms of bandwidth, gain, radiation patterns and current distribution have been investigated. The antenna exhibits high performance, including an impedance bandwidth of 19 GHz ranging from 23 GHz to 42 GHz, results in 58.46% wider relative bandwidth calculated at 10 dB scaled return loss, a peak realized gain of 6.75 dBi, optimal radiation efficiency of 89%, stable omnidirectional-shaped radiation patterns and robust current distribution across the antenna structure at multiple resonances. The designed antenna has been fabricated and simulation experiments evaluated its performance. The results demonstrate that the antenna is appropriate and can be well integrated into 5G millimeter-wave wireless communication systems.

Ka-Band Huygens Antenna Array With Very High Aperture Efficiency and Low Sidelobes

A Ka-band Huygens antenna array with extremely high aperture efficiency (AE) and low sidelobe levels is reported for 5G millimeter-wave (mm-wave) wireless applications. The basic array element is an innovative Huygens subarray consisting of two open rectangular waveguides that form an aperture consisting of a 1 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> 2 set of orthogonal, tightly coupled electric and magnetic elements separated by a virtual gap that are balanced, in- phase, and radiate Huygens cardioid patterns. A larger 8 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times16$ </tex-math></inline-formula> element array is then realized with 64 of these 1 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> 2 subarrays. With excitations of equal amplitude, the full broadside-radiating array achieves an AE up to 97.5% in the operating bandwidth, which is very close to the 100% limit associated with an ideal uniform aperture distribution. Moreover, a highly efficient and compact feed network with tapered-amplitude and in- phase excitations from the array center to its edges is designed to achieve sidelobe and backlobe levels less than −20 dB. The −10 dB impedance bandwidth covers 26.7–29.65 GHz, and the peak realized AE (RAE) reaches 82%. A full-aluminum array prototype was fabricated with standard machining processes and tested. The measured performance characteristics agree well with their simulated values, confirming the efficacy of their designs.

Design of a Compact Dual-Frequency Microstrip Antenna using DGS Structure for Millimeter-Wave Applications

In this paper, a Millimeter-wave (MMW) antenna has been proposed for a current and future wireless application. The proposed model has two resonances at 30.5 GHz and 52.4 GHz. The proposed model has been designed and optimized using a commercial electromagnetic simulator (CST-Studio) and focused on attaining a return loss rate that is lower than -10 dB. The proposed MMW models are built on a small thick Rogers Substrate (RT-5880) with h = 0.508 mm for the thickness, relative permittivity of εr = 2.2, and tanδ = 0.0009 for the loss tangent, while the substrate has a width w_s equal to 6 mm and a length l_s equal to 6 mm. The design process of the model came at three steps, the first step after mathematical calculations has an output of model which has feeding port of 50 ohm with a feedline base length l_b of 0.5 mm and a feedline length l_f of 3 mm, the second step was by using the tapering techniques for enhancing matched impedance after initial calculations to have a length of tapering l_t equal to 1.8 mm, then finally extracting four corner slots to the patch for creating the final proposed model. The previous design process is to assure reliability, mobility, and high efficiency for the proposed antenna. The advantages of this model are the small size, low profile, low fabrication cost, and straightforward design structure. The proposed design can be employed for a variety of Millimeter-wave applications like wireless personal area network (WPAN) and 5G application in some countries like Colombia and Mexico. The proposed model has a moderate gain of 3 dBi to 7 dBi at resonance frequencies of 30.5 GHz and 52.4 GHz, which is one of the unique characteristics of the proposed antenna. The impedance bandwidth is between 28.7 Ghz and 32.6 GHz, which is equal 3.9 GHz, and 49.7 GHz to 56.2 GHz, which is equal to 6.5 GHz respectively for the proposed model, and satisfying efficiency of about 75% and 87% as calculated by CST -Studio, and a VSWR is equal to 1, All of these positive results are more than enough to satisfy the needs of millimeter-wave wireless applications.

Ka-Band Stacked Power Amplifier Supporting 3GPP New Radio FR2 Band n258 Implemented Using 45 nm CMOS SOI

This paper presents a fully integrated, four-stack, single-ended, single stage power amplifier (PA) for millimeter-wave (mmWave) wireless applications that was fabricated and designed using 45 nm complementary metal oxide semiconductor silicon on insulator (CMOS SOI) technology. The frequency of operation is from 20 GHz to 30 GHz, with 13.7 dB of maximum gain. The maximum RF (radio frequency) output power (Pout), power-added efficiency (PAE) and output 1 dB compression point are 20.5 dBm, 29% and 18.8 dBm, respectively, achieved at 24 GHz. The error vector magnitude (EVM) of 12.5% was measured at an average channel power of 14.5 dBm at the center of the the 3GPP/NR (third generation partnership project/new radio) FR2 band n258—i.e., 26 GHz—using a 100 MHz 16-quadrature amplitude modulation (QAM) 3GPP/NR orthogonal frequency division modulation (OFDM) signal.

A Broadband H-plane Printed Horn Antenna with Sandwich Substrate Structure for Millimeter-wave Applications

Antenna is a very important element and plays a key role in communication systems for radiating energy. Based on high data rate speed requirements and large volume multimedia applications, 3G, 4G and now 5G technologies have been introduced and implemented. This paper presents a low profile antenna with novel structure and large continuous bandwidth for 5G broadband and millimeter-wave wireless applications. It is an H-plane printed horn antenna with multi-layered sandwich substrate. There are two Rogers (RO3003(tm)) substrates that make a sandwich structure with eight stainless steel columns. The proposed antenna is expected to give an impedance bandwidth 20-45 GHz with S11 &lt;-10dB and 8.64dBi gain at 28 GHz design frequency. ANSYS 18.2 HFSS simulator is used for designing and optimization of the profile antenna. A comparison between simulated and measured results confirms the validity of the proposed design.

(40 to 65) GHz Higher Order Mode Microstrip-Based Dual Band Dual Beam Tunable Leaky-Wave Antenna for Millimeter Wave Applications

This article proposes a microstrip leaky-wave antenna with dual symmetrical side beams for complete $V$ -band radiation coverage. The frequency sweeping dual-beam scanning is obtained from 50–65 GHz due to wideband excitation of the microstrip second higher order mode. Appropriate metallic via hole placement realized a back-to-back half-mode pair, which can also generate two symmetrical side beams in the E-plane with enhanced gain within 40–55 GHz. Mode switching was achieved electronically by incorporating p-i-n diodes with a proper biasing network. The final antenna design was prototyped to validate the design concept. The leaky band in microstrip higher order modes was analyzed by dispersion characteristics and Bloch impedance. An operating frequency range and a scanning range in the H-plane were obtained from 50–65 GHz with 12°–80° for unbiased state and 41–53 GHz with 20.4–76° for biased state, respectively. The antenna exhibited a measured 10 dB return loss bandwidth of 26% and 27.65% and a peak gain of 19 and 18.6 dBi, for the two states, respectively, with average sidelobe level of <−15 dB and minimum cross-polarization of 25 dB. The simulated results agreed well with the experimental data, thus validating this single-layered structure for millimeter-wave wireless applications.

60 GHz Compact Larger Beam Scanning Range PCB Leaky-Wave Antenna Using HMSIW for Millimeter-Wave Applications

A half-mode substrate integrated waveguide (HMSIW), based on printed circuit board (PCB) technology, is employed to construct a novel V-band leaky-wave antenna incorporating composite right-/left-handed (CRLH) media. Including modified half-sinusoidally varied interdigital capacitive slots on the radiating edge of the HMSIW enables the feature of effective CRLH media to produce adequate radiation coverage and bandwidth with improved sidelobe level (SLL) and higher gain. Unit cell characteristics and space harmonic analysis were thoroughly investigated through dispersion and Bloch impedance analysis. By appropriately tuning the physical parameters of the design, the balanced condition was obtained at a broadside frequency of 60 GHz. The highly directed radiated fan beam covered a scanning range of 120° with beam steering from -72° to 48° of the visible space. The proposed antenna operated over 55-65 GHz with a maximum realized gain of 14.5 dBi, maximum beamwidth of 9.15°, better than 15 dB SLL and 20 dB cross-polar radiation. All simulated responses showed reasonably good accordance with experimental data thereby validating the novel design of the proposed leaky-wave structure for millimeter-wave wireless applications.

Wideband Millimeter-Wave Dual-Mode Dual Circularly Polarized OAM Antenna Using Sequentially Rotated Feeding Technique

In this letter, a 2 × 2 wideband bidirectional dual circularly polarized (CP) orbital angular momentum (OAM) antenna array at millimeter-wave frequency is presented, which can be used to generate dual mode simultaneously by the sequential rotation feeding method. The proposed antenna array is composed of four bidirectional radiating dual CP elements that rotate 90° sequentially to each other in the clockwise direction. The antenna element structure consists of two metasurface patch layers that are loaded on the bidirectional cavity-back slot antenna based on substrate integrated waveguide technology. Results indicate that the left-hand circular polarization (LHCP) with a mode lOAM = -1 in the +z-direction and right-hand circular polarization (RHCP) with a mode lOAM = +1 in the -z-direction, over a wide impedance (S11 <; 10 dB) and 3 dB axial-ratio relative bandwidth of 32.3% from 26 to 36 GHz. An acceptable agreement has been achieved with the comparison between the measurement and simulation results. The proposed antenna provides a method of generating multimode OAM beams for wideband millimeter-wave wireless communication applications.

A Ka-Band Wideband Dual-Polarized Magnetoelectric Dipole Antenna Array on LTCC

A Ka -band wideband dual-polarized magnetoelectric (ME) dipole antenna with the feeding structure consisting of two orthogonal L-shaped probes with different heights is presented based on the low-temperature cofired ceramic (LTCC) technology. A simulated overlapped impedance bandwidth of 42.5% is achieved together with an isolation of higher than 24 dB between the two input ports and stable radiation characteristics over the operating band. By combining the radiating elements with a single-layered feed network composed of microstrip lines, a $4\times 4$ dual-polarized ME dipole antenna array is designed, fabricated, and measured. An overlapped impedance bandwidth of 45% that can cover the entire Ka -band, a gain up to 16.1 dBi, and stable symmetrical radiation patterns in the two orthogonal planes with cross polarization of less than −15 dB are experimentally confirmed. With advantages of the compact geometry, wide operating band, and promising radiation performance, the proposed antenna array with dual polarization would be attractive for millimeter-wave wireless applications in Ka -band.

A $Ka$ -Band 3-D-Printed Wideband Stepped Waveguide-Fed Magnetoelectric Dipole Antenna Array

A novel millimeter-wave aperture-coupled magnetoelectric (ME) dipole antenna with a low-profile metallic geometry is proposed based on the 3-D printing technology. An impedance bandwidth of 53.7%, a gain up to 10.8 dBi, and stable unidirectional radiation patterns with the cross polarization of less than -38 dB are achieved by the antenna. Its operating mechanism and design process are studied in detail as well. In order to widen the bandwidth of the millimeter-wave fullcorporate H-plane air-filled waveguide feed network, a wideband H-plane stepped waveguide T-junction with a compact size is then investigated, which has a bandwidth of about 50% for the reflection coefficient of less than -20 dB. By combining the presented radiating element with the feed network, an 8 x 8 ME dipole array is designed, printed, and tested in the Ka-band. An enhanced bandwidth of 31%, symmetric radiation patterns with the cross polarization of less than -35 dB, and a gain varying from 25.5 to 28.5 dBi are experimentally obtained. The proposed design demonstrates the advantage of utilizing the 3-D printing method to improve the operating characteristics of the millimeter-wave antenna array and is attractive for the emerging wideband millimeter-wave wireless applications.

3-D Printed High-Gain Wideband Waveguide Fed Horn Antenna Arrays for Millimeter-Wave Applications

3-D printed air-filled waveguide fed horn antenna arrays are investigated in the Ka -band. Pyramidal E-plane horn antennas with a small size are introduced as the radiating element to improve the bandwidth and radiation characteristics of the array. Commercial direct metal laser sintering technology is applied to print the antenna structure in a whole piece. Excellent operating performance including wide impedance bandwidths of 25.8% and 23.8% for $\vert \text{S}_{11}\vert dB, gains up to 27.5 and 33.8 dBi with a variation of less than 1.5 dB over the operating band and radiation efficiencies of around 90% and 80% is obtained experimentally by two fabricated prototypes consisting of 64 and 256 radiating elements, respectively. Stable radiation patterns with low cross polarization are confirmed as well. The array designs and results obtained in this paper verify the feasibility of utilizing advanced a 3-D printing technique to realize millimeter-wave large-size antenna arrays with complicated multilayered configurations, which is of value for various wideband millimeter-wave wireless applications.

Low-Cost Empty Substrate Integrated Waveguide Slot Arrays for Millimeter-Wave Applications

In this letter, two slot arrays with high radiation efficiency are proposed based on the empty substrate integrated waveguide (ESIW) technology. The arrays consist of four FR-4 substrate layers that function as cavity loading, radiation slots, ESIW feeding network, and feeding port, respectively. The $1\times 6$ -slot array shows a measured −10 dB bandwidth of 12.7% (36.1–41.0 GHz) with a measured maximum gain of 15.5 dBi and radiation efficiency of 90.7% at 38 GHz. The $8\times 6$ -slot array shows a measured −10 dB bandwidth of 12.1% (36.4–41.1 GHz) with a measured maximum gain of 24.0 dBi and radiation efficiency of 86.5% at 39 GHz. Additionally, stable radiation patterns are obtained in the operating band. These arrays provide a low-cost way for broadband millimeter-wave wireless applications including the fifth-generation mobile communications.

Air-Filled Substrate Integrated Waveguide Fed Magneto-Electric Dipole Antenna Array for Millimeter-Wave Applications

A substrate integrated magneto-electric (ME) dipole antenna array with an improved radiation efficiency is presented in the 28-GHz band. A novel full-corporate air-filled substrate integrated waveguide (SIW) feed network with low losses is designed and realized by utilizing the low-cost printed circuit board (PCB) facilities. Different from most previous millimeter-wave planar arrays consisting of 2 × 2 subarrays, an SIW fed sub-array with a larger size of 2 × 4 is investigated to simplify the configuration of the major portion of the array feed network, which is of importance to the successful realization of the air-filled SIW feed network. An 8×8 array prototype with a four-layered geometry is fabricated and measured to verify the design. The array has an impedance bandwidth of 25.9%, a gain up to 26 dBi and stable radiation patterns over the operating band. Benefitted from the absence of the significant dielectric loss in the feed network, a high antenna efficiency of 80% is also achieved. The proposed design provides an effective method to improve the achievable gain and efficiency characteristics of the substrate integrated arrays with a large size that are attractive for millimeter-wave wireless applications.

Spoof Surface Plasmon Polaritons Fed Frequency-Scanning Open-Loop Antenna Arrays

Spoof surface plasmon polaritons (SSPPs) fed open-loop elements without a metallic ground plane are investigated for the SSPPs-based antenna design. By employing a straight SSPPs section close to the open end of the loop as the feed, the one-wavelength and one-and-a-half-wavelength modes of the open-loop are excited effectively, which can generate radiation fields with orthogonal polarizations. Based on the open-loop arrays operating in different modes, two Ka-band SSPPs-fed leaky-wave antennas with frequency-scanning in the H- or E- plane are then designed, fabricated and measured. Wide impedance bandwidths, stable gain of around 13 dBi and radiation efficiency of higher than 70% are confirmed experimentally. The studies in this letter provide a new means to adjust the polarization features of the SSPPs-fed antennas. Benefitted from the compact single-layered geometry that is easy to integrate with circuits and good radiation performance, the proposed SSPPs-fed antenna arrays would be an attractive candidate for future millimeter-wave wireless applications.

Dual-Polarized Quasi Yagi–Uda Antennas With Endfire Radiation for Millimeter-Wave MIMO Terminals

This paper presents a novel design of compact dual-polarized multi-input and multi-output (MIMO) antennas with endfire radiation for millimeter-wave wireless applications. The low-cost printed circuit board process serves as the basis for the design, fabrication, and measurement of the proposed dual-polarized quasi Yagi–Uda antennas. Addressing the potential antenna locations in a mobile terminal, this paper investigates both the corner and the lateral design of antenna modules. Each design incorporates dual-port dual-polarized antennas co-located in a compact area. The lateral design is further extended to a linear $1 \times 4$ array for high-gain and phased-scanning operation. Experimental results show that the proposed compact dual-polarized quasi Yagi–Uda antennas are very suitable for MIM terminals of next-generation (5G) mobile communications.

A 60 GHz Horizontally Polarized Magnetoelectric Dipole Antenna Array With 2-D Multibeam Endfire Radiation

A novel substrate integrated waveguide (SIW) fed horizontally polarized endfire magnetoelectric (ME) dipole antenna composed of an open-ended SIW with broad walls vertical to substrates and a pair of electric dipoles realized by four metallic patches is proposed. Simple configuration and excellent performance including an impedance bandwidth of 46.5%, stable gain of around 6 dBi, and symmetrical cardioid radiation patterns with low backward radiation and low cross polarizations are achieved. An SIW 90° twist integrated in three-layered substrate is implemented in order to connect the ME-dipole antenna conveniently to the SIW beam-forming network with broad walls parallel to substrates. A $4 \times 4$ SIW Butler matrix with a three-layered zigzag topology is then designed, which enables a size reduction of 45% for the matrix compared with conventional single-layered configuration but not affecting its operating characteristics. By employing a $2 \times 4$ ME-dipole array with 90° twists, two-folded Butler matrices and four SIW 3 dB E-plane couplers, a multibeam endfire array that can radiate eight beams scanning in two dimensions is designed at the 60 GHz band. The fabricated prototype verifies that a wide impedance bandwidth of 22.1%, gain varying from 10 to 13 dBi and stable radiation beams can be obtained. Due to good performance and the compact structure with low fabrication costs, the proposed design would be attractive for future millimeter-wave wireless applications including 5G communications and the WiGig system.