End-fire Radiation Research Articles

A Compact Wideband Endfire Filtering Antenna Inspired by a Uniplanar Microstrip Antenna

This letter presents a design of a compact wideband endfire filtering antenna. The design starts from an endfire quasi-microstrip antenna, which is unidirectional with a smaller size when compared with a Yagi–Uda antenna. A reflector and a parasitic patch are utilized to introduce two new resonant frequencies to broaden the bandwidth. They also generate two radiation nulls at the lower band and the higher band, respectively. The endfire radiation mechanism can be modeled by a two-element antenna array. The mechanism of these two radiation nulls is explained by the mixed coupling theory. Therefore, the proposed antenna also shows filtering property without any extra circuits. In addition, a capacitive feeding structure is employed to improve the level of the reflection coefficient within the upper stopband. The measured results reveal that the proposed antenna has a bandwidth of 41.9% from 2.00 to 3.06 GHz and a peak gain of 7.3 dBi with an extremely small size of 0.105 λ <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> (λ is the wavelength at the center frequency). Two radiation nulls are observed at 1.78 and 3.19 GHz, respectively. The out-of-band roll-off of the antenna gain achieves 15 dB.

A Planar Pattern-Reconfigurable Antenna With Stable Radiation Performance

In this letter, a planar antenna withreconfigurable radiation pattern is investigated for smart Wi-Fi systems. The design incorporates one pair of folded dipoles, a microstrip-to-via feeding balun and two reconfigurable parasitic strips which are near-field excited by the dipole pair. By controlling the states of two Pin diodes embedded in two reconfigurable printed lines, the proposed antenna can switch between one omnidirectional mode and two unidirectional endfire radiation modes. This optimized antenna exhibits a decent size of 0.5 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> × 0.38 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> ×0.004 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> (where λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> is free space wavelength at 2.45 GHz). Good agreement is observed between the simulated and measured results. The overlapped impedance bandwidth with | <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> | < −10 dB for the three pattern modes is from 2.34 to 2.6 GHz in the measurement. Throughout the overlapping bandwidth, the front-to-back ratios are higher than 15 dB for the two unidirectional radiation modes and out-of-roundness is less than 1.2 dB for omnidirectional radiation mode. The measured peak realized gain of the proposed pattern-reconfigurable antenna is 6 dBi. This proposed Wi-Fi antenna is well poised for intelligent Wi-Fi communication systems.

A thin shared radiator based ACS‐fed orthogonal pattern diversity antenna with physical tilt for mmWave 5G access points

A low profile and compact two-port antenna is proposed for mmWave 5G access point applications. Since the overall space inside a typical mmWave 5G access point is limited, a small form factor based antenna module is proposed. The two-port antenna shares a common radiator that miniaturizes the overall antenna module. The proposed antenna comprises of single-layered asymmetric coplanar strip (ACS)-fed shared radiator with wide operating bandwidth ranging from 25 to 31 GHz that accounts for fractional bandwidth of 21.4%. The two-port antenna elements are oriented at right angles to each other for obtaining orthogonal pattern diversity (OPD) thereby obtaining wide angular coverage in the E-plane. Vertical linear corrugations with varying lengths are incorporated for decreasing mutual coupling between these two antenna elements and producing a uniform high gain end-fire radiation pattern. Isolation of around 4 dB is enhanced by insertion of these vertical corrugations. The proposed antenna attains peak gain of 7.2 dBi with high pattern integrity over the entire operational frequency band. The presented OPD antenna occupies overall area of 74.75 mm2 which is minimal. Moreover, implementation of the proposed antenna inside a typical mmWave 5G access point is also demonstrated. Simulation and measured results are presented with adequate technical explanation.

RIT Logo based Slotted PLPCMA Multi-Band Patch Antenna

A compact Printed Log-Periodic Curvilinear Monopole Array (PLPCMA) antenna having a Defected Ground Plane (DGP) is proposed and examined. The proposed array of curvilinear monopoles is designed on a FR-4 substrate having a dielectric constant of 4.4. The designed antenna is multi-band operated having its resonance in the regions of S band (2GHz to 4GHz), X band (8GHz to 12GHz) and C band (4GHz to 8GHz). The design reveals Voltage Standing Wave Ratio (VSWR) lesser than 1.5 has been achieved at resonating frequencies 2.49GHz, 3.28GHz, 6.84GHz and 8.36GHz with fractional bandwidth of 4.02, 3.66, 50.58 and 41.39 percentages respectively. The presented antenna exhibits unidirectional end-fire radiation pattern with peak realized gain of 7. 1145dBi.The measured results depicts that PLPCMA antenna has good -10dB impedance bandwidth of 158% from 1.58GHz to 15GHz (9.49:1) and suits for Wi-Fi/WIMAX UWB applications.

Millimeter-Wave Wideband Endfire Magnetoelectric Dipole Antenna Fed by Substrate Integrated Coaxial Line

A wideband endfire magnetoelectric (ME) dipole antenna fed by substrate integrated coaxial line (SICL) is presented. Endfire radiation is achieved by the combination of a horizontally oriented quarter-wave shorted patch and a dipole array loaded at the patch aperture. A direct-feeding mechanism based on the SICL structure is developed to excite the ME-dipole antenna. The proposed feeding method provides a simple yet effective mean of wideband impedance tuning. The antenna exhibits a wide impedance bandwidth of 77%, covering from 23.1 to 52 GHz, and a small lateral 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">$0.32\lambda _{0}$ </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">$\lambda _{0}$ </tex-math></inline-formula> refers to the wavelength in free space at the center frequency, i.e., 38 GHz). In addition to its wideband performance and compactness, highlights, including a stable gain of around 5.5 dBi, low backward radiation, and low cross polarization, are also achieved. In particular, the proposed design outperforms most state-of-the-art millimeter-wave endfire antennas with a notable bandwidth.

Dual-Purpose Planar Radial-Array of Rectenna Sensors for Orientation Estimation and RF-Energy Harvesting at IoT Nodes

A dual-purpose radial-array rectenna is presented as a potential sensor candidate for RF-energy harvesting (EH)-enabled Internet of Things (IoT) nodes along with orientation sensing capability. The proposed design comprises eight rectenna elements placed radially in azimuth to capture RF energy from entire 360° angular region to improve tolerance for angular misalignment and make the design orientation-oblivious. As dual-purpose, the capability to sense its own orientation with respect to the transmitter is additionally provided. Each rectenna consists of a horizontally polarized compact planar scoop-shaped antenna designed at 5.8 GHz having endfire radiation pattern with 7-dBi gain. The dc power patterns of the proposed design are calibrated and used to estimate orientation using minimum mean square error (MMSE) method. The design is verified experimentally, and the results indicate average orientation estimation error of 1.0822° with 0.9242° standard deviation and improved stability in energy-harvesting compared to single rectenna element for varying orientation of IoT nodes.

Orthogonally Dual-Polarized Leaky-Wave Antenna for Endfire Radiation Based on Periodical Loading

We propose a dual-polarized leaky-wave antenna (LWA) with orthomode based on a metallic square waveguide for broadband endfire radiation applications. Several double-sided slots acting as radiation elements are notched on the waveguide to produce an endfire pattern. To overcome the restriction associated with the endfire radiation condition of a linear array, a metallic core periodically loaded with pins is used to control the dispersion of the proposed double-sided-slot waveguide. By optimizing the height distribution of the loading pins along the longitudinal direction using a cosine function, stable endfire radiation can be achieved over a broad operating band. Moreover, dual-polarized radiation can be automatically implemented because of the rotational symmetry of the proposed LWA. Furthermore, two rectangular waveguides connected with a square waveguide are used as the orthomode transducer (OMT) of the proposed LWA. The numerical and experimental results verify that dual-polarized endfire radiation is achieved in the frequency range of 7.6–9.1 GHz with an isolation of higher than 45 dB. The realized gain achieved is in the range of 13–15 dBi with a cross-polarization level of below −30 dB.

A compact five-element printed MIMO antenna with pattern and polarization diversity for 2.45 GHz WLAN applications

A five-element pattern and polarization (linear/circular) diversity multiple-input-multiple-output (MIMO) antenna system has been presented in this article for application in 2.45 GHz WLAN. The proposed configuration consists of a circularly polarized (CP) patch antenna element and four monopole antenna elements placed orthogonal to each other. Broadside CP characteristics are achieved by using a square patch antenna with circular chamfered corners and central axis feed. Simple rectangular monopole antenna elements with microstrip line feed produce four linearly polarized (LP) end-fire directive radiation patterns. It achieves a bandwidth (BW) of 24.1% and 5.1% for the end-fire LP antenna element and broadside CP antenna element (corresponding axial ratio BW is 1.64%), respectively, with minimum port isolation of 15 dB. The ECC and CLL are below 0.03 and 0.5 bits/s/Hz, respectively, showing good MIMO performance. Due to its simple design, compact footprint (93 × 93 mm2), planar structure, and competitive features, the proposed antenna is suited for practical WLAN applications.

Wideband and Aperture-Efficient Traveling-Wave Endfire Antenna Designs Using the First Higher-Order Transmission Line Mode

In this article, we propose a traveling-wave endfire antenna based on the first higher-order transmission line (TL) mode, and it features wide bandwidth, high gain, and large aperture efficiency. We propose two essential conditions for the realization of the proposed wideband endfire antenna. First, the dispersion curve of the first higher-order mode should be made close to that of the air line across a wide frequency band. Second, the fundamental mode should be suppressed to allow single higher-order mode operation across a wide frequency band. Following these principles, we provide a design for an endfire antenna based on a periodically slotted parallel stripline, where the periodic meandered slots suppress the fundamental mode and hence allow single higher-order mode radiation. To verify the proposed approach, a prototype has been designed and fabricated. The antenna can achieve endfire radiation within a 1:2 frequency band (8.5–17.5 GHz), with an average gain of 10.7 dBi, and large aperture efficiency up to 6.38 dBi/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda ^{2}_{0}$ </tex-math></inline-formula> .

Compact and Planar End-Fire Antenna for PicoSat and CubeSat Platforms to Support Deployable Systems

A miniaturized planar Yagi-Uda antenna for integration with PicoSats or other SmallSat missions is proposed. Miniaturization techniques, such as meandering and 1-D artificial dielectric concepts to reduce the guided wavelength, are employed to overcome space constraints imposed by the SmallSat footprint while still maintaining good performance for the FR-4 antenna. Simulations and measurements have been carried out on the Unicorn-2 PicoSat chassis from Alba Orbital and are in good agreement. Also, antenna dimensions have been reduced between 15% and 66% when compared to a more conventional planar Yagi-Uda antenna working at the same frequency. This compactness allows for simple integration with the deployable solar panel array of the Unicorn-2 PicoSat spacecraft. Full end-fire radiation is achieved and peak gain values are about 5 dBi for the antenna when fully integrated on the satellite chassis, offering an attractive solution for downlink connectivity. This compact antenna design can also be used within an array for beam steering or integrated within the solar cell modules of other PicoSats, CubeSats and SmallSats. Applications include Earth observation, remote sensing, as well as SmallSat to ground station communications. The planar Yagi-Uda antenna may also be useful wherever end-fire radiation is required from a compact antenna structure.

Dual-Band Antenna With Large Beam Steering Angle Incorporating Endfire and Frequency Scanning Modes Using Double-Layer SSPPs Structure

A dual wideband antenna with a large beam steering angle through endfire radiation and frequency scanning radiation in each band is proposed for the first time. The antenna utilizes a double-layer (D-L) spoof surface plasmon polaritons (SSPPs) structure which exhibits stronger field confinement and lower cutoff frequency than the single-layer (S-L) SSPPs structure. The modulated D-L SSPPs structure can excite the space harmonic distributing in the fast-wave region and retains transmission in the slow-wave region. By combing the modulated D-L SSPPs waveguide and the Vivaldi radiator, both the slow-wave radiation (endfire mode) and the fast-wave radiation (frequency scanning mode) can be aroused in the two operating bands. An example antenna is designed and fabricated. In the slow-wave range from 3 to 9 GHz, the antenna works in the endfire mode with the beam direction of 90° and the realized gain varying from 3.55 to 8.24 dBi. Within the fast waveband from 13 to 34 GHz, the antenna operates in the frequency-scanning mode, accomplishing beam scanning from −90° to ±42.5° with the realized gain of 9.45–15.67 dBi. Thus, the proposed dual-band antenna can achieve two operating bands and two radiation modes, which offers a 180° beam-changing angle in total.

Spoof Surface Plasmon Polariton Endfire Antenna Possessing Bidirectional and Unidirectional Radiation Pattern

A simple approach is proposed to design a new type of endfire antenna, which simultaneously possesses bidirectional and unidirectional radiation pattern in wideband. By the dispersion engineering, different frequency bands spoof surface plasmon polariton (SPP) modes are excited at the two ports of a proposed splitter structure, and the two ports of the splitter structure are directly connected with two radiator structures, which are utilized to decouple the different frequency bands spoof SPP to free space wave by dispersion mismatching, achieving bidirectional and unidirectional radiation pattern in different frequency bands. From 8.4 to 21.6 GHz, this designed spoof SPP antenna possesses bidirectional endfire radiation pattern, and from 21.6 to 45.0 GHz, this designed spoof SPP antenna possesses unidirectional endfire radiation pattern. This designed spoof SPP antenna has an average gain over 10.6 dB in the whole working bandwidth, and the relative bandwidth of this antenna is 137%. Both the simulation and measurement results verify that the stable bidirectional and unidirectional radiation pattern of this proposed endfire spoof SPP antenna in wide bandwidth are achieved.

Helix Inspired 28 GHz Broadband Antenna with End-Fire Radiation Pattern

This paper presents the design and characterization of a via free planar single turn helix for 28 GHz broadband applications. The proposed antenna is designed using ROGERS RO4003 material, having a simple structure and end-fire radiation pattern. The antenna comprises of a compact dimension of 1.36 λ0 × 0.9 λ0 with a thickness of 0.0189 λ0 (where λ0 is the free-space wavelength at the central frequency of 28 GHz). Parametric study has been carried out to investigate the impact of key design parameters and to achieve an optimum design. Results show a good agreement between the simulated and measured results. A single turn helical inspired antenna covers −10 dB impedance bandwidth of 26.25–30.14 GHz having a peak gain of 5.83 dB and radiation efficiency up to 85%. Moreover, linear array configurations with 2 and 4 elements have been analyzed for applications with higher gain and space constraints. Presented array configurations are suitable for applications having space constraints in one dimension. Results show that peak gain up to 8.2 dB and 11.1 dB can be achieved with 2 and 4 elements, respectively. Due to its simple planar and via free structure, this antenna is suitable for 5G communications and for sensing, imaging, IoT and tracking applications at 28 GHz band spectrum.

Modulated Scalar Reactance Surfaces for Endfire Radiation Pattern Synthesis

Complete 1-D aperture fields are synthesized to design planar modulated reactance surfaces for endfire radiation characteristics. The evanescent part of the aperture fields is introduced and optimized to render the aperture surface passive and lossless everywhere. Characterized by a position-dependent, scalar surface reactance distribution mounted on an infinite conducting ground plane, the aperture radiates space waves with a prescribed far-zone pattern when excited by a TM-polarized surface wave (SW). The design technique is presented together with a few pattern synthesis examples. Physical conductor groove array metasurfaces excited by coax-fed SW launchers are simulated to confirm the practical realizability of the synthesized reactances.

Franklin Collinear Antenna 2 Levels Different Sides using Array Method 4 Stacking Units 360ᵒ with Integrated Reflector and Power Combiner for ADS-B S-Receiver Mode

In this study, an antenna system that could cover the 360ᵒ detection area using the microstrip method was created. The antenna design proposed uses the franklin collinear method with the addition of an array of arms to the left and right of the antenna and the addition of reflectors as a gain enhancer. The four antenna array units are combined using a power divider (combiner) as a unifying antenna. Antenna design with end fire radiation pattern cannot be used in receiving the ADS-B antenna system, because it works only in certain sectors with certain beamwidth, so it needs to be modified by adding an array of 4 units that make up 360◦ radiation of directional diagrams. The addition of the reflector is done by testing the optimum width. The most optimum width is obtained by the width of the side addition on the side of the antenna aperture cross section width of 80 mm. Based on the results of experiments that have been carried out for the design of receiver antennas for ADS-B applications that are required in the form of a radiation pattern in all directions using the reflector technique, the most appropriate gain increase is to use a phase difference for the antennas that are closest both left and right by 90o in ¼ λ conditions in the integration process using a 4 way power combiner. Response return loss at frequency 1.0752 GHz and 1.109 GHz is -15 dB, it means antenna has 33.8 MHz bandwidth with maximum response return loss at -23.22 dB and gain of 7.586 dBi, this antenna design is very suitable for use in the ADS-B application. Design and simulation at this antenna used CST software.

Theoretical analysis of a graphene quantum well hybrid plasmonic waveguide to design an inter/intra-chip nano-antenna

In this paper, a smart multi-user wireless link based on a graphene quantum well vertical hybrid plasmonic waveguide-fed nano-antenna is proposed. The theoretical method and finite element method (FEM) are used to verify that the vertical hybrid plasmonic waveguide (VHPW) supports both even and odd fundamental modes. Utilizing multi-mode graphene quantum well VHPW leads to the design of a selective mode nano-antenna with intermediate broadside and end-fire radiation patterns with high directivities of 9.38 dBi and 11.8 dBi at 193.5 THz, respectively, obtained by the finite-difference time-domain method. Also, to verify the accuracy of nano-antenna results, the FEM approach is used. The nano-antenna performance as a wireless inter/intra-chip link is investigated, which confirms the even mode plays a key role to create a multiple-access wireless system. Based on the amazing features of graphene as an epsilon-near-zero and absorptive/transparent material, the accessibility of receivers is easily controlled. The effect of a single row array structure and its application as beam steering is studied. Finally, to estimate the performance of quantum well nano-antenna as a real device, which is compatible with electron-beam lithography and lift-off fabrication techniques, the effect of metal layer roughness and 5% tolerance for geometrical parameters are investigated.

Broadband Dual-Polarized Antenna Array With Endfire Radiation for 5G Mobile Phone Applications

This letter presents a wideband compact dual-polarized antenna with endfire radiation pattern for the fifth-generation millimeter-wave (mm-wave) applications. The antenna achieves a –10 dB <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> bandwidth of 16.5% (25–29.5 GHz). The antenna has a thickness of 1.6 mm and a clearance of 3.4 mm. The presented four-element array achieves a maximum realized gain of 9.9 and 9.1 dBi for horizontal mode (H-mode) and vertical mode (V-mode), respectively. The antenna has a wide beamwidth in both elevation and azimuth planes with good scanning performance for both H-mode and V-mode.

A Grooved Half-Mode Waveguide Leaky-Wave Antenna for Vertically-Polarized Endfire Radiation

A high-gain low-profile leaky-wave antenna (LWA) for vertically-polarized (VP) fixed-beam endfire radiation is proposed in this article. The LWA is composed of two back-to-back half-mode waveguides with grooves etched at the margins of both radiation edges. By etching grooves, the phase velocity of the traveling wave can be tailored to slower than the wave velocity in free space for fitting the Hansen–Woodyard condition. Compared with periodic LWAs, the proposed antenna continuously radiates at two symmetric apertures, contributing to a high endfire gain. A prototype is fabricated and tested to validate the concept. The measured and simulated results are in good agreement. A simulated gain of 14.29 dBi and a measured gain of 13.37 dBi are achieved within an antenna length of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.05\lambda _{0}$ </tex-math></inline-formula> . Moreover, a measured overlapping bandwidth of 2.74–3.17 GHz (14.3%) is realized with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$S_{11} &lt; - 10$ </tex-math></inline-formula> dB and gain variation less than 3 dB. To the best of the authors’ knowledge, the proposed VP endfire LWA realizes the highest aperture efficiency and shows great advantages in high gain, low profile, and wide bandwidth.

Design of a Dual-Linearly Polarized Endfire Antenna

In this article, a dual-linearly polarized endfire antenna is proposed with high gain and stable radiation patterns. A double-sided slot array antenna (DSSAA) and a corrugated rectangular metal strip (CRMS) are employed to realize vertical and horizontal polarization (HP), respectively. Omnidirectional radiation pattern is obtained by etching transverse slots on both sides of the top and bottom metallic plates of a cavity. Based on the double-sided slot antenna, a DSSAA is proposed and fed by an air-substrate parallel strip line (PSL) for stable endfire radiation patterns. Then, the top plate of the DSSAA is reused as a CRMS for HP and compact size. To verify this concept, an all-metal prototype was fabricated and measured. Both the simulation and experimental results show that the DSSAA and the CRMS could offer the highest endfire gains of 12.5 and 12.9 dB, respectively, within a footprint of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.47\lambda _{0} \times 0.72\lambda _{0} \times 0.13\lambda _{0}$ </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">$\lambda _{0}$ </tex-math></inline-formula> is the free-space wavelength at the center frequency). Moreover, an overlapping bandwidth of 7.6% is realized with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert S_{11}\vert &lt; -10$ </tex-math></inline-formula> dB, gain variation less than 3 dB. This work may provide useful references for designing dual-polarized endfire antennas with stable radiation patterns, high gain, and compact size.

Miniaturized Dual-Band Broadside/Endfire Antenna-in-Package for 5G Smartphone

This paper proposes a miniaturized antenna in package (AiP) for 5G millimeter-wave smartphone that incorporates broadside and end-fire arrays and supports a dual band covering 28 and 39 GHz. This paper demonstrates that the proposed AiP is 5.8 mm × 19 mm × 1.122 mm. It is believed that this is the smallest 5G AiP that can support a 10 dBi antenna gain, a 10 dB return-loss bandwidth of 3 GHz, and more than 10 dB isolation for both broadside and end-fire arrays. AiP consists of a 1 × 4 patch antenna array for broadside radiation and a 1 × 4 dipole antenna array for end-fire radiation. To miniaturize the patch antenna elements, a multi-layer Reactive Impedance Surface (RIS) is embedded between the patch layer and the ground plane. This multi-layer RIS idea greatly fits in 5G PCB-stack up antennas where each stack-up layer essentially requires certain portion of copper area. For the end-fire array antenna miniaturization with bandwidth improvement is achieved by modifying the Vertically Bent Folded Dipole Antenna (VBFDA) and adding a tightly-coupled T-shape side via wall. The AiP achieves a 10 dB return-loss bandwidth of 26.22 to 29.57 GHz and 35.18 to 41.00 GHz for Multi-Layer RIS Patch Antenna(MLRPA), and 26.40 to 29.74 GHz and 36.65 to 40.72 GHz for VBFDA. The antenna gain is 11.6 dBi for MLRPA and 10.0 dBi for VBFDA.