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Showing papers on "Feed line published in 2020"


Journal ArticleDOI
TL;DR: In this paper, an ultra-compact two-port MIMO antenna working in the frequency range of 3.1-10.6 GHz with dual band-notched characteristics is presented.
Abstract: In this paper, an ultra-compact two-port MIMO antenna working in the frequency range of 3.1–10.6 GHz with dual band-notched characteristics is presented. The MIMO antenna consists of two identical octagonal-shaped radiating elements placed adjacent to each other with a connected ground plane. The overall size of the proposed two-port UWB-MIMO antenna is 19 × 30 × 0.8 mm3. In the ground plane of antenna elements, a T-shaped stub is introduced to create band-notch at 5.5 GHz. Also, an open-ended half-guided-wavelength resonator slot is introduced along the upper edge of the octagonal radiator to obtain a broader notched-band (4.37–5.95 GHz). The second band-notch is created around 7 GHz (6.52–7.45 GHz) by etching another open-ended slot from the radiating patch. The two-notch bands reject interference due to HiperLAN, WiMAX, INSAT/Super-extended C-band, downlink of X-band satellite communication and RFID service bands. A pair of L-shaped slits are introduced in the feed line to improve impedance matching, for the frequency band available between the two notches. The proposed design is fabricated on an FR-4 substrate and minimum isolation greater than 18 dB (a major portion >22 dB) and envelope correlation coefficient (ECC) less than 0.13 are obtained. The antenna gain varies in the range of 1.2–2.91 dBi with a variation of 1.71 dBi only. A radiation efficiency, greater than 70% is achieved throughout the operating frequency band.

61 citations


Journal ArticleDOI
Chi Fan1, Bian Wu1, Yue Hu1, Yu-Tong Zhao1, Tao Su1 
TL;DR: In this article, a pattern reconfigurable antenna consisting of a pair of back-to-back modified Vivaldi antennas with two graphene nanoplate pads symmetrically loaded on the feed line is proposed to realize dynamical manipulation of gain.
Abstract: In this communication, a millimeter-wave (MMW) pattern reconfigurable Vivaldi antenna utilizing graphene-based tunable resistor is proposed. First, a modified Vivaldi antenna with high front-to-back ratio is achieved by equal proportion slotting on the ground patch. Then, a pattern reconfigurable antenna consisting of a pair of back-to-back modified Vivaldi antennas with two graphene nanoplate pads symmetrically loaded on the feed line is proposed to realize dynamical manipulation of gain. By applying bias voltage from 0 to 4 V, the resistance of the graphene pad can be gradually reduced from 200 to $20~\Omega $ . Two slots located on the ground allow two graphene pads to be dc interruption for independent resistance control. By varying the resistance of two graphene pads, the radiation pattern of Vivaldi antenna can be manipulated from two opposite beams to a single beam. Finally, a prototype antenna centering at 30 GHz with a bandwidth of 16.6% is fabricated and measured, which realizes reconfigurable radiation beams at 90° and/or 270° with three states.

54 citations


Journal ArticleDOI
TL;DR: In this paper, a low-cost beam-steerable antenna operating at 28 GHz is presented for 5G mobile terminal applications, which has a sandwich-like stack structure, including ten patch elements, a ground plane with two rows of slots, and a long microstrip transmission feed line.
Abstract: A low-cost beam-steerable antenna operating at 28 GHz is presented for 5G mobile terminal applications. The proposed array has a sandwich-like stack structure, including ten patch elements, a ground plane with two rows of slots, and a long microstrip transmission feed line. The radiators and the transmission line are placed at the two sides of the ground plane, which provides great flexibility in designing the radiating pattern and the feed network. Switches are added on the transmission line to construct periodic distributed phase shifters for beam steering. The 2 bit phase shifter with phases of 0°, 90°, 180°, and 270° is formed without using phase delay lines. Continuous beam steering is achieved, and the steerable angle is 121° in the upper hemisphere. Two location configurations of the proposed array in 5G mobile terminals are analyzed and the angular coverage range is evaluated. The array can cover 38.8% of the hemispherical space with a gain threshold of 10 dBi.

36 citations


Journal ArticleDOI
TL;DR: In this paper, the design and development of a dual-band and dual-polarized two-port multiple-input-multiple-output (MIMO) antenna for mid-band 5G (3.4-3.6 GHz) and C-band (4-8 GHz) applications is presented.
Abstract: This paper presents the design and development of a dual-band and dual-polarized two-port multiple-input-multiple-output (MIMO) antenna for mid-band 5G (3.4–3.6 GHz), and C-band (4–8 GHz) applications. The antenna design is very simple and it mainly consists of a circular-shaped single split-ring resonator on the top side of the substrate which is coupled with the microstrip line feed line. The bottom side is comprised of a rectangular-shaped defected ground structure. Due to this dual-band response is obtained and the first band shows linear polarization and the second band provides circular polarization. The entire dimensions of the intended two-port MIMO antenna are 46 mm × 21 mm × 1.6 mm. The antenna measured results offer a wider impedance bandwidth (IBW) of 20.22% and 44.07% for the two bands centered at 3.54 GHz and 6.33 GHz respectively. Also, the proposed MIMO antenna shows minimum isolation of 15 dB for the two frequency bands with a smaller edge-to-edge spacing of 4 mm (0.04λ0) between the two antenna elements. Moreover, the second band provides an axial ratio bandwidth of 3.97% centered at 6.78 GHz. The antenna shows excellent IBW, good isolation between the single antenna elements without the use of any decoupling mechanism, better antenna gain, and improved envelope correlation coefficient by maintaining smaller antenna size compared to similar types of existing two-port MIMO antennas in literature.

35 citations


Journal ArticleDOI
TL;DR: Results confirm that the proposed on-chip antenna with compact dimensions, wide bandwidth over the terahertz domain, low profile, cost effective, simple configuration, and easy to manufacture can be potentially appropriate for teraherstz integrated circuits.
Abstract: This research work presents the investigation of realizing an on-chip antenna based on the metamaterial concept, which is working over the terahertz (THz) band for applications in integrated circuits. The proposed on-chip antenna is constructed of five stacked layers of polyimide and aluminum as top and bottom substrates, radiation patches, ground plane, and feed line. The four square-shaped radiation patches are implemented on the 50 m top-polyimide substrate, and the feed line is realized on the 50 m bottom-polyimide layer by designing the simple square microstrip lines, which are all connected to each other and then excited by waveguide port. The ground plane including a coupling square slot has sandwiched between the top- and bottom-polyimide layers. The coupling square slot etched on the ground plane is exactly placed under the patch to optimum transfer the electromagnetic signal from the bottom feed line to the top radiation patch. To achieve high performance parameters without increasing the antenna's physical dimensions, the metamaterial and substrate integrated waveguide properties have been applied to the antenna structure by implementing linear tapered slots on the patch top surfaces and metallic via holes throughout the middle ground plane connecting top and bottom substrates to each other. The slots play the role of series left-handed (LH) capacitors (CL) and the via holes act as shunt LH inductors (LL). The overall dimension of the proposed metamaterial-based on-chip antenna is 1000 × 1000 × 100 μm3. This antenna can cover the frequency band from 0.6 THz to 0.622 THz, which is equal to 20 GHz bandwidth. The radiation gain and efficiency across the operating frequency band varies from 1.1 dBi to 1.8 dBi, and from 58% to 60.5%, respectively. The results confirm that the proposed on-chip antenna with compact dimensions, wide bandwidth over the terahertz domain, low profile, cost effective, simple configuration, and easy to manufacture can be potentially appropriate for terahertz integrated circuits.

34 citations


Journal ArticleDOI
TL;DR: In this article, the design of a compact loop antenna with independent frequency tuning is presented, which consists of a feed line fed by a $50~\Omega $ coaxial probe and four resonating arms on the adjacent sides of the feed line.
Abstract: This communication presents the design of a compact loop antenna with independent frequency tuning. The proposed antenna consists of a feed line fed by a $50~\Omega $ coaxial probe and four resonating arms on the adjacent sides of the feed line. The two outer resonating arms are directly coupled to the feed line and the other two inner resonating arms are coupled to the outer arms. The proposed antenna has a footprint of 25 mm $\times 10$ mm $\times0.2$ mm. The designed antenna operates at 0.9, 2.4, 3.5, and 5.5 GHz. Each of these bands is individually tuned using varactor diodes. Thus, the aggregation of these tunable bands provides wide bandwidth. The impedance bandwidth and percentage bandwidth of the antenna are 270/1000/400/700 MHz and 33%/47.6%/11%/12.7%, respectively. Furthermore, the gain and efficiency of the antenna are 1.7/1.3/2.1/2 dBi and 60%/63%/65%/69%, respectively. The prototype antenna is fabricated and tested. The measured impedance and radiation characteristics of the antenna are in good correlation with the simulation results.

28 citations


Journal ArticleDOI
TL;DR: A planar 2 × 2 filtering patch antenna array with high selectivity and wide stopband is investigated for marine communications, and a larger 4 × 4 filtering array is designed by just using a traditional four-way power dividing network.
Abstract: A planar 2 × 2 filtering patch antenna array with high selectivity and wide stopband is investigated for marine communications. The 2 × 2 patch array is composed of a driven patch and four identical parasitic patches placed nearby. A forked-microstrip-line-coupled rectangular slot is used to excite the driven patch, while the neighboring parasitic patches are capacitively coupled by the driven patch. Owing to the hybrid feeding effect of the forked feed line, a radiation null can be generated at the lower band-edge. Simultaneously, another radiation null can be generated at the upper band-edge owing to the radiation cancellation effect between the driven patch and the parasitic patches. Consequently, no power dividing feeding network is required for the 2 × 2 array, and the quasi-elliptic bandpass filtering response is achieved without utilizing any complex filtering/non-filtering circuits. In addition, the proposed filtering array exhibits a wide stopband capable of suppressing the second-harmonic radiation effectively. Based on this 2 × 2 array, a larger 4 × 4 filtering array is further designed by just using a traditional four-way power dividing network. For validation, both of the 2 × 2 and 4 × 4 filtering patch arrays operating at 5.25 GHz are fabricated and tested. The measured results show that the two patch arrays have comparable impedance bandwidths of about 4.4%. The in-band peak gains are given by 11.1 and 15.5 dBi respectively, which are suitable for the long-distance shore-to-ship communications.

26 citations


Proceedings ArticleDOI
01 Aug 2020
TL;DR: In this paper, a microstrip filtering Class-F is proposed based on the couple-line multimode impedance transformer (IT) in which four TPs are created by using only a single resonator.
Abstract: Filtering power amplifiers (PAs) combine two functions into one circuit and 2-order cascaded structure with two transmission poles (TPs) is the most common form. Multiple TPs can extend bandwidth and minimize in-band ripple. However, more resonators are required for traditional topologies, resulting in large size with high loss. A microstrip filtering Class-F is proposed based on the couple-line multimode impedance transformer (IT) in this paper. Four TPs are created by using only a single resonator. Lengths of the drain bias stub and coupled feed line are carefully chosen to meet the requirement for Class-F operation. The fabricated multimode filtering Class-F PAs is measured at 3.6 GHz for 5G applications. Maximum gain at saturation is 12 dB with output power P out >38.5 dBm. Maximum power added efficiency (PAE) is 63%, while the effective bandwidth is 400 MHz under the condition of PAEs > 50%.

15 citations


Proceedings ArticleDOI
15 Mar 2020
TL;DR: Novel wideband passive and active efficient wearable metamaterial antennas for IOT, BAN and 5G applications are presented in this paper.
Abstract: Efficient small antennas are crucial in the development of wearable wireless communications and medical systems. Low efficiency is the major disadvantage of small antennas. Meta materials technology and active components are used to improve the efficiency of small antennas. Moreover, the dynamic range and the efficiency of communication system may be improved by using active wearable antennas. Amplifiers may be connected to the wearable antenna feed line to increase the system dynamic range. Novel wideband passive and active efficient wearable metamaterial antennas for IOT, BAN and 5G applications are presented in this paper. The gain and directivity of antennas with Split-ring resonators, SRR, is higher by 2.5dB than the antennas without SRR. The resonant frequency of the antennas with SRR is lower by 4% to 11% than the antennas without SRR. The resonant frequency of the antenna with SRR on human body is shifted by 3% to 5%. Active small wearable antennas may be used in receiving or transmitting communication systems. For example, the active metamaterial antenna gain is 13+3dB for frequencies from 0.1GHz to 0.8GHz. The active antenna Noise Figure is 0.5+0.3dB for frequencies from 0.1GHz to 0.8GHz.

15 citations


Journal ArticleDOI
TL;DR: In this article, a microstrip-line fed ultra-wideband (UWB) antenna with sextuple rejection bands is presented and investigated, which consists of an elliptic radiation and a rectangle ground plane.
Abstract: In this paper a microstrip-line fed ultra-wideband (UWB) antenna with sextuple rejection bands is presented and investigated. The antenna consists of an elliptic radiation and a rectangle ground plane. The band rejections at worldwide interoperability for microwave access (MiMAX) band (2.96–3.33 GHz and 3.73–3.88 GHz) are achieved by etching an elliptic split ring resonator (ESRR) and a round split ring resonator (RSRR) in the radiating patch. Four various sizes of U-shaped parasitic strips near the feed line have been used to accomplish the band rejection characteristics at INSAT band (4.43–4.53 GHz), WLAN band (5.37–5.57 GHz), and C-band (7.02–7.30 GHz and 7.56–8.06 GHz). Simulated results indicate that the center frequency of each desired frequency can be adjusted independently without affecting the other bands by altering its corresponding parameters. Furthermore, the performance analysis of the equivalent circuit model of the proposed antenna is presented. The experimental and measured results of reflection coefficient provide evidences that the proposed antenna has a wide impedance with six rejection bands. Moreover, the radiation pattern and peak gain of the proposed antenna have also been investigated. Similarly, the good agreement between the simulated and measured results ensures the suitability of the proposed antenna for UWB applications.

14 citations


Journal ArticleDOI
TL;DR: The proposed non-planar 3D-MIMO antenna system can be employed for indoor localization systems and wireless personal area network applications, where different 5G devices are wirelessly linked to a centralized server.
Abstract: In this article, a low-cost 16-port non-planar Multiple-Input-Multiple Output (MIMO) antenna system is proposed for future 5G applications. The non-planar MIMO antenna system is established around a 3D-octagonal-shape polystyrene block. The MIMO elements are arranged on the eight-sides of octagonal-shape block, whereas bottom and top faces of polystyrene block are left void. The single antenna element comprises of slotted microstrip patch with a stepped chamfered feed line and defected ground plane. Each MIMO element is designed on FR-4 substrate with a size of 22 mm × 20 mm, to cover the frequency band of 3.35 GHz to 3.65 GHz for the fifth-generation (5G) applications. The isolation between array elements is improved by using a meander-lines based near-zero-index epsilon-negative (NZI-ENG) metamaterial decoupling structure. The array elements are placed on the top-layer, whereas common connected ground plane and decoupling structure is placed on the bottom-layer. The metamaterial-based decoupling structure offers an isolation of more than 28 dB for antenna elements arranged in across and side-by-side configuration. Moreover, simulated and measured MIMO performance parameters i.e. Total Active Reflection Coefficient (TARC) <; -18 dB, Envelop correlation coefficient (ECC) <; 0.1 and Channel capacity loss (CCL) <; 0.3 are in acceptable limits. The proposed non-planar 3D-MIMO antenna system can be employed for indoor localization systems and wireless personal area network applications, where different 5G devices are wirelessly linked to a centralized server. Moreover, a good agreement between simulated and measured results is achieved for the non-planar MIMO antenna system.

Journal ArticleDOI
TL;DR: A new vertical director has been employed to have a highly directive horizontal radiation pattern and to obtain a high optical power signal and steering the beam angle, the antenna gain and directivity have been calculated with two different types of array structure by controlling the relative phase shift between the array elements and elements number.
Abstract: In this paper, a wideband InP-based hybrid plasmonic nano-antenna (HPNA) operating at telecommunication wavelengths has been proposed. Monolithically integrating InP-based lasers with hybrid plasmonic waveguide (HPW) as a feed line of the proposed HPNA on the same InGaAsP/InP wafer can increase the antenna efficiency. A new vertical director has been employed to have a highly directive horizontal radiation pattern. This enhancement is attributed to the efficient coupling between the radiation patterns of arm elements as well as reduced side lobes and back-lobes levels due to the achieved impedance matching. As a result, the directivity has been increased considerably, 3.6 dBi at 193.5 THz (1550 nm) and 1.1 dBi at 229 THz (1310 nm). The HPNA shows the high directivity, total efficiency and quality factor of 11.8, 97.49% and 94.57, respectively. Further, to verify the validity of confining the fundamental TM mode to a thin layer with the lower refractive index, both theoretical and numerical methods have been employed. Therefore, we have derived an analytical formula to investigate the HPW dispersion relation based on the transfer matrix theory and genetic algorithm. Moreover, due to the HPNA ability to receive an optical signal from free space and transmit it to the waveguide based on the reciprocity theorem, the HPNA performance as an optical wireless on-chip nano-link has been investigated analytically and numerically. Additionally, to obtain a high optical power signal and steering the beam angle, the antenna gain and directivity have been calculated with two different types of array structure by controlling the relative phase shift between the array elements and elements number. To validate the array design performance, a three dimensional full-wave numerical simulation and array factor theory have been exploited. The HPNA fabrication is compatible with generic foundry technology.

Journal ArticleDOI
TL;DR: In this paper, a low profile modified Koch fractal shaped boundary, ultrawideband (UWB) multiple input multiple output (MIMO) antenna is presented, where the radiators are elliptically tapered from the feed line with triangular shaped loading.
Abstract: A low profile modified Koch fractal shaped boundary, ultrawideband (UWB) multiple input multiple output (MIMO) antenna is presented. The radiators are elliptically tapered from the feed line with triangular shaped loading. The boundaries of the triangular shaped loading are embedded with modified Koch fractal shape to provide improved impedance matching. A band suppression characteristic at 5.5 GHz is incorporated by using an electric inductive capacitive resonator at the back of the substrate. Enhanced port isolation of

Journal ArticleDOI
TL;DR: A stepped planar microstrip structure is proposed and demonstrated as a candidate of the ultra-wideband (UWB) antenna and can have an improvement in the in-band characteristics while extending the operating bandwidth.
Abstract: A stepped planar microstrip structure is proposed and demonstrated as a candidate of the ultra-wideband (UWB) antenna in the paper. In the structure, two L-shaped slots are introduced into the rectangular microstrip patch to broaden the current path at both edges of the radiating patch. The impedance bandwidth of the antenna can be extended by using the stepped impedance resonator (SIR) structure at one end of the radiation patch and connecting with the feed line. The symmetrical two I-shaped slots are loaded on the SIR microstrip to improve in-band performance and further widen the operating band. The proposed new structure can have an improvement in the in-band characteristics while extending the operating bandwidth. A broadband impedance bandwidth of 2.39 GHz to 13.78 GHz at S11 < −10 dB is demonstrated based on the proposed novel structure. The reflection coefficient and radiation characteristics are characterized in the paper. The tiny antenna, with the benefit of small area 36 mm × 23 mm, shows potential applications in ultra-wideband communication systems, wireless energy harvesting systems, and other wireless systems.

Journal ArticleDOI
01 Jan 2020-Heliyon
TL;DR: The results strongly support the applicability of current antenna model with band notching in wideband communications.

Journal ArticleDOI
TL;DR: In this paper, an electromagnetic band gap (EBG) metasurface (MS) superstrate-based circularly polarized antenna for the WiMAX (3.5 GHz) band is proposed.
Abstract: In this paper, an electromagnetic band gap (EBG) metasurface (MS) superstrate-based circularly polarized antenna for the WiMAX (3.5 GHz) band is proposed. The proposed structure comprises a 2 × 2 slot-loaded rectangular patch MS array that can be perceived as a polarization-dependent EBG MS superstrate. Furthermore, to achieve circular polarization, the proposed antenna has an inclined coupling slot onto the ground with a conventional coplanar waveguide feed line. The proposed antenna has a compact structure with a low profile of 0.037λ0 (λ0 stands for the free-space wavelength at 3.48 GHz) and a ground size of 30 × 30 mm2. The measured results show that the −10 dB impedance bandwidth for the proposed antenna is 34.6% and the 3-dB axial ratio (AR) bandwidth is 6.8% with a peak gain of 3.91 dBi in the desired operating band. Good agreement between the simulated and the measured results verifies the performance of the proposed antenna.

Journal ArticleDOI
TL;DR: The dispersion relation of a circular hybrid plasmonic waveguide as the feed line of the proposed nano-antenna has been derived, analytically and the directivity and realized gain have been obtained based on the array factor theory and numerical methods, which are agree with each other.
Abstract: In this paper, a circular hybrid plasmonic waveguide-fed nano-antenna (CHPWFNA) has been introduced for operating at the standard telecommunication wavelength of 1,550 nm. For the first time, the dispersion relation of a circular hybrid plasmonic waveguide as the feed line of the proposed nano-antenna has been derived, analytically. To verify the accuracy of the analytical solution, two numerical techniques of finite element method (FEM) and finite-difference time-domain (FDTD) method have been used. Numerical results are well-matched with the theoretical ones. The characteristics of the CHPWFNA have been studied by two mentioned methods. The obtained realized gains (directivities) by the FDTD and FEM simulations are 9.03 dB (9.38 dBi) and 10.00 dB (10.32 dBi), respectively, at 1,550 nm wavelength. For on-chip point-to-point wireless link performance, the obtained quality factor by the FDTD method (FEM) is 63.97 (100). The obtained radiation characteristics and link performance reveal that at 1,550 nm, the proposed antenna has the best performance. Besides, the frequency bandwidth of the antenna (185-200 THz) covers the low-loss optical frequency range. Also, paying attention to the laser eye safety is so important. Consequently, the wavelength of 1,550 nm has been chosen as the target wavelength. Moreover, the array configuration has been studied and the directivity and realized gain have been obtained based on the array factor theory and numerical methods, which are agree with each other. The attained realized gain by the FDTD method (FEM) for the considered single row array, at 1,550 nm, is 11.20 dB (11.30 dB). There is a little difference between the numerical results due to the total mesh size, the grid size refinement and the relative error of the numerical methods convergence. Finally, as one of the most important challenges in fabrication is the gold surface quality, we have studied the effect of gold surface roughness and its pentagonal cross section on the antenna performance.

Journal ArticleDOI
01 Jan 2020
TL;DR: In this article, the authors proposed an aperture coupled micro strip patch antenna (AC-MPA) for long range (≈400 km) air surveillance radars, where the input signal couples to the radiating patch through the aperture (slot) that appears on the ground plane of the feed line.
Abstract: The aperture coupled- Micro strip Patch Antenna (AC-MPA) is designed for long range (≈400 ​km) air Surveillance radars The design of patch antennas with aperture coupled power feed is crucial and designed for 1 ​GHz–2 ​GHz (D-band) frequency The proposed aperture coupled feed design gives wideband behavior, better return loss, gain, Voltage Standing Wave Ratio (VSWR), less compatibility and smaller in size by applying aperture feed The theoretical analysis is done manually and designed using Advanced Design System (ADS) In aperture coupled feeding technique, the input signal couples to the radiating patch through the aperture (slot) that appears on the ground plane of the feed line and with their feeding structure of the radiating patch element it is different from other micro strip patch antenna In this work, the design and implementation of aperture coupled patch antenna are analyzed in terms of return loss, gain, efficiency, directivity and power parameters and compared with inset line feeding The proposed design gives 5 ​dB gain, 45 ​dB directivity, efficiency of 30%, impedance bandwidth of above 15% higher than inset feed line with 15 ​GHz as centre frequency The maximum return loss of-40dB is achieved compared to −19dB with aperture feed compared to inset feed line micro strip patch antenna with proper impedance matching The main advantage of this antenna over single layered patch antenna is increased bandwidth and this antenna will act as dual band also with variation in air gap (1 ​mm–5 ​mm) between single and aperture coupled patch antenna

Journal ArticleDOI
TL;DR: In this article, the authors proposed the application of a slot in the ground plane, Defected Ground Structure (DGS), of a microstrip patch antenna to attenuate higher-order excited modes without deteriorating the antenna parameters in the fundamental mode.
Abstract: This work proposes the application of a slot in the ground plane, Defected Ground Structure (DGS), of a microstrip patch antenna. The application of this technique aims to attenuate higher-order excited modes without deteriorating the antenna parameters in the fundamental mode. The methodology for the design of the slot in H-format is presented, based on the physical dimensions of the microstrip patch antenna. The positioning of the DGS concerning the feed line was determined from a detailed parametric analysis. The antenna was designed for the fundamental mode at 2.45 GHz frequency. Two antenna prototypes were built, with and without DGS, and measurements of reflection coefficient, gain, and radiation pattern were performed. The measured results show that the application of DGS considerably attenuated higher-order excited modes. A good agreement between simulated and measured results is achieved.

Journal ArticleDOI
TL;DR: This study determines, in theory, the smallest achievable capacitive loading with different line types and experimentally validates the approach to design feed lines that function as transmission lines at mm-wave frequencies but correspond to open circuits at sub-6GHz.
Abstract: The co-existence of millimeter-wave (mm-wave) and sub-6GHz antennas in a smartphone presents many performance-limiting aspects. When both antennas are attached to the metal frame, the feed lines of the mm-wave antennas might short-circuit the sub-6GHz antennas, and thus, may significantly affect their performance. This paper presents a method to design feed lines that function as transmission lines at mm-wave frequencies but correspond to open circuits at sub-6GHz. This study determines, in theory, the smallest achievable capacitive loading with different line types and experimentally validates the approach. The capacitive loading due to the feed line is small enough to maintain the sub-6GHz performance. At the mm-wave band, the insertion loss of the line is 1dB with a measured reflection coefficient below −10dB. The introduced common-mode capacitive load of the feed line on the sub-6GHz antennas corresponds to 0.19pF capacitance.

Journal ArticleDOI
26 May 2020
TL;DR: In this article, a mutual coupling reduction technique using filtering structures between two antennas resonating in adjacent frequency bands is proposed, which can be easily applied to either mobile terminal or 5G CPE (Customer Premise Equipment) devices where both 5G and Wi-Fi are installed.
Abstract: In this paper, a mutual coupling reduction technique using filtering structures between two antennas resonating in adjacent frequency bands is proposed. Two patch antennas resonating at low band (4.8-5.0 GHz, part of 5G Band N79) and high band (5.15-5.35 GHz, part of IEEE 802.11 ax 5 GHz Band), which are close to each other in frequency spectrum, are used as an illustrative example. The decoupling structure consists of two open-loop resonators with filtering function coupled to the feed line on its edges. By loading the filtering structures, the isolation between the two antennas is improved from poorer than 15 dB to more than 25 dB when the reflection coefficients are still satisfactory in their respective operating frequency bands, showing significant improvements compared to the reference antennas where no filtering structures are introduced. The proposed method can be easily applied to either mobile terminal or 5G CPE (Customer Premise Equipment) devices where both 5G and Wi-Fi are installed as well as many other antennas with similar application scenarios.

Journal ArticleDOI
TL;DR: In this article, a planar inverted-F antenna (PIFA) is proposed to cover mobile application devices like GPS, WLAN/Wi-Fi, WiMAX, 4G LTE, UWB, and satellite applications.
Abstract: This paper presents, new compact and multiband frequency reconfigurable planar inverted-F antenna (PIFA). The antenna is designed and optimized to cover mobile application devices like GPS, WLAN/Wi-Fi, WiMAX, 4G LTE, UWB, and satellite applications. The frequency reconfigurability is obtained by using only a single RF switch (PIN diode) for changing the operating frequency. The antenna dimensions are 45.6x39.6x1.6 mm 3 printed on an FR-4 epoxy substrate with relative dielectric constant er = 4.3, loss tangent tan (δ) = 0.002 and 50 Ω coaxial feed line. The proposed antenna has two patches connected by a single PIN diode. The antenna introduces nine resonant frequencies under (S11 ≤ -10 dB) which are: 0.980 GHz, 3.392 GHz, 3.924 GHz, 4.554 GHz, 5.82 GHz, 6.81 GHz, 7.305 GHz, 8 GHz and 8.105 GHz in the ON and OFF states of the PIN diode which are applicable to cover GSM900, WLAN/Wi-Fi, WiMAX, 4G LTE, UWB, and satellite systems. The obtained maximum simulated gain is 8.45 dB at 6.81 GHz. The lowest return loss is obtained to be -42 dB at 5.854 GHz. Detailed simulation and measurement results are explored and studied in this research. The CST software is used to simulate and optimize the proposed PIFA antenna. The proposed antenna has been fabricated and produced a good agreement with the simulation results.

Journal ArticleDOI
30 Jun 2020
TL;DR: In this paper, a high gain dual resonance patch antenna is designed and simulated and the analysis is done while changing geometry and dielectric thickness of the antenna while achieving gain of 8.85dB and 6.59dB for 4.94GHz and 7.38GHz, respectively.
Abstract: In this work a high gain dual resonance patch antenna is designed and simulated. Analysis is done while changing geometry and dielectric thickness. Main advantage of this type of antenna is its compact structure. Due to its dual characteristics it is very demanding in the communication industry which makes designing and analysing of this type of antenna more alluring. Values for S11 parameters are: -10.97dB and –30dB for 4.94GHz and 7.38GHz, respectively. Gain exceeds 8.85dB and 6.59dB for 4.94GHz and 7.38GHz, respectively. Characteristic impedance of the feed line is 50?.

Journal ArticleDOI
TL;DR: In this paper, a wideband filtering dielectric resonator antenna (DRA) is demonstrated, which is obtained by integrating a triple pole cross-resonator filter in the feed line of the slot coupled rectangular DRA.
Abstract: A wideband filtering dielectric resonator antenna (DRA) is demonstrated in this paper. The filtering characteristics is obtained by integrating a triple pole cross-resonator filter in the feed line of the slot coupled rectangular DRA. The transmission poles of the resonator are adjusted in order to get the wideband filtering response. The proposed filtering DRA offers an impedance bandwidth of 15% from 3.06 GHz to 3.56 GHz. Electric field distribution of DRA within the passband confirmed that the rectangular DRA drives in TE111 mode which ensured the broadside radiation. A satisfactory stable gain pattern of 5.9 ± 0.3 dBi within the pass-band has been achieved. The gain response falls sharply with two radiation-nulls beyond the passband at 3.9 GHz and 4.4 GHz and that increases the selectivity of the antenna. In conclusion, proposed design offers a robust technique to convert a conventional slot coupled rectangular DRA into a wideband antenna along with frequency selective gain response. Proposed configuration manifests as an ideal contender for some specific uses in S-band such as Wi-Max, TD-LTE (Time-Division Long Term Evaluation) application as it avoids the interference adjacent bands.

Proceedings ArticleDOI
28 Feb 2020
TL;DR: A multi-band frequency reconfigurable planar bow-tie antenna is designed and simulated in this paper and shows two different states by switch the PIN diode.
Abstract: A multi-band frequency reconfigurable planar bow-tie antenna is designed and simulated in this paper. Firstly, a self-complementary bow-tie antenna is designed and implemented; this antenna is characterized by a simple feeding. It is directly matched to the SMA connector via $50 \Omega$ micro-strip feed line. Second, a rectangular slot and a PIN diode are added to adjust electronically the bow-tie antenna over (1.7-6GHz) frequency band. The proposed antenna shows two different states by switch the PIN diode. In ON state, the antenna covers DCS, Bluetooth and Wlan bands and in OFF state the antenna covers the wide-band (2-4.9GHz) and Wlan band. Moreover, hexagonic parasitic elements are integrated in the bottom and in the top side of the substrate to cover (1.49-1.7GHz) and (1.77-1.85GHz) bands. By switching PIN diode, multi-band frequencies’ are shown in the ON and the OFF states with a gain varied between 0.5 and 3.5dB.

Journal ArticleDOI
TL;DR: In this paper, a uniplanar asymmetric coplanar strip (ACS) fed antenna with closed V-shaped radiating patch of size printed on FR4 substrate with loss tangent ( = 0.02, height (h)=1.6mm, and dielectric constant of 4.4 covering WiMAX, X-band and WLAN applications is presented.
Abstract: In the proposed paper, a uniplanar asymmetric coplanar strip (ACS) fed antenna with closed V-shaped radiating patch of size printed on FR4 substrate with loss tangent ( =0.02, height (h)=1.6mm, and dielectric constant of 4.4 covering WiMAX, X-band and WLAN applications is presented. The proposed closed V-shaped radiating patch is formed by joning two rectangular stubs. The resultant shape of the radiating patch is obtained by adding rectangular strips to feed line until desired multiband results are achieved. The advantage of this structure is that it forms simple configuration as well as helps the overall antenna in attaining three distinict useful frequency band with good impedance matching for S11<-10 dB criteria. The proposed ACS fed antenna operates at 3.1 (WiMAX), 5.0 (WLAN) and 9.9 (X-band) GHz with impedance bandwidth ranging from 2.7-3.9 GHz, 4.4-5.5 GHz and 9.5-10.3 GHz in simulation. Under measurement the proposed antenna shows multiband phenomenon at 3.2, 5.3 and 9.7 GHz with impedance bandwidth ranging from 2.8-3.7 GHz, 4.6-5.4 GHz and 9.4-10 GHz, respectively. The antenna exhibits simulated gain of 2.51, 1.18 and 1.96 dB at the corresponding frequency bands of 3.1, 5.0 and 9.9 GHz. The key parameters of the antenna like length and width of the multi-branched strips are optimized to get the multiband operation. The deisign simulation is carried out in Ansys HFSS (High frequency Simulation Software) where different characteristics of the proposed antenna are investigated. The evolution and optimization process is dealt in detail with the help of S 11 , VSWR, current distributions, radiation patterns and gain.

Proceedings ArticleDOI
01 Jan 2020
TL;DR: In this paper, a slotted rectangular patch antenna for the E and W band was proposed for resolving the issues of compactness, gain and efficiency of antenna designs for future generation 5G devices such as watches, and dongles.
Abstract: A novel slotted rectangular patch antenna for E and W band, which resonates at the frequency of 67 GHz and has impedance bandwidth of 13.2 GHz, is used for resolving the issues of compactness, gain and efficiency of antenna designs for future generation 5G devices such as watches, and dongles. The single element antenna, having a dimension of 5.5 × 4.7 × 0.381 mm3, with a realized gain of 8.9 dBi was achieved. A rectangular slot was placed in the ground plane, just under the feed line of a microstrip patch antenna (MSPA), and this works as a defected ground structure (DGS): this improved the gain by up to 2 dB in the proposed design. The partial ground is used for tuning the impedance bandwidth. The rationale for the DGS, the partial ground, and the effect of the slot technique are discussed and implemented in this paper.

Proceedings ArticleDOI
06 Oct 2020
TL;DR: In this paper, a compact microstrip patch antenna (RMPA) using systematic coplanar waveguide (CPW-Fed) dual-band inverted U-slotted shaped printed antenna has been designed for WiMAX/WLAN applications.
Abstract: A compact microstrip patch antenna (RMPA) using systematic coplanar waveguide (CPW-Fed) dual-band inverted U-slotted shaped printed antenna has designed for WiMAX/WLAN applications in this paper. Represent the antenna has an axial ratio is near about 2. A prototype CPW-Fed antenna was fabricated with FR4 Substrate with a dielectric constant of 4.3 and thickness $\mathrm{h}=1.6$ mm. The antenna primarily consists of an asymmetrical coplanar waveguide with inverted U-slotted patch and excite by a $50\ {\Omega}$ CPW feed line for impedance matching to generate wide quad operating bands. This antenna is suitable for the range from 2.51 GHz to 3.96 GHz and 5.2–5.9 GHz. It is designed miniaturized CPW-Fed microstrip patch antenna has a compact size $35\ \mathrm{mm} \times 39\ \mathrm{mm}$ . This antenna to improve the gain, impedance bandwidth and also have lower return losses, better impedance matching. The main purpose of this work is to propose a wideband and improved gain antenna for mobile WiMAX, Wi-Fi/WLAN as well as military applications. The simulated results show that the proposed antenna has achieved wider bandwidth with a satisfactory gain by introducing a probe fed with shorting pin in the assistant of the partial ground plane.

Journal ArticleDOI
TL;DR: In this article, a wideband dual sense circularly polarized (CP) asymmetric circular slot fed by coplanar waveguide is proposed and designed, and the measured value of 10 dB impedance bandwidth is 112% at frequencies from 4.2 GHz to 14.9 GHz with voltage standing wave ratio (VSWR) ≤ 2.
Abstract: Wideband, dual sense circularly polarized (CP), asymmetric circular slot fed by coplanar waveguide is proposed and designed. Dual polarizations are obtained by using a horizontal stub to the feed line and embedding the L-shaped strip onto the slotted ground plane. The simulated result of impedance bandwidth shows wideband performance is produced by four resonant modes. Some key parameters are studied to analyze the characteristics of the proposed antenna. The overall volume of the proposed antenna is 18 mm × 18 mm × 1.6 mm. The measured value of 10 dB impedance bandwidth is 112%at frequencies from 4.2 GHz to 14.9 GHz with voltage standing wave ratio (VSWR) ≤ 2. The 3-dB axial ratio bandwidths are 39.3% for the lower band which senses right-hand circular polarization (RHCP) and 2.8% for the upper band which senses left-hand circular polarization (LHCP) relative to the center frequency of 6.1GHz and 14.1 GHz, respectively. The proposed structure gives a good radiation pattern with moderate gain.

Journal ArticleDOI
TL;DR: In this article, a quadruple notched frequency bands ultra wideband (UWB) antenna is proposed, which is a semicircular-shaped monopole type of a compact size 36x24 mm, covering frequency range of 3.02-14 GHz.
Abstract: This paper proposed quadruple notched frequency bands ultra-wideband (UWB) antenna. The antenna is a semicircular-shaped monopole type of a compact size 36x24 mm, covering frequency range of 3.02-14 GHz. Four rejected narrow bands including WiMAX (3.3-3.7GHz), ARN (4.2-4.5 GHz), WLAN (5.15-5.825GHz), X-Band (7.25-7.75) have been achieved using inserting slots techniques in the patch, feed line, and ground plane. The slots dimensions have been optimized for the required reject bands. The antenna design and analysis have been investigated by simulation study using CST-EM software package. The antenna characteristics including impedance bandwidth, surface current, gain, radiation efficiency, radiation pattern have been discussed.