Band Wireless Applications Research Articles

Design of a Compact Wideband Two-Port MIMO Antenna for NR 5G Sub-6 GHz Band Wireless Applications

Design of a Compact Wideband Two-Port MIMO Antenna for NR 5G Sub-6 GHz Band Wireless Applications

A nested square combination of ε-negative high EMR symmetric metamaterial structure for triple band wireless applications

In this article, a novel metamaterial is presented that is constructed with split ring resonators (SRR) arranged in a nested square configuration. The proposed metamaterial unit cell is constructed over a 1.5 mm thick FR-4 substrate with electrical dimensions of 0.11 λ × 0.11 λ, where λ is the wavelength calculated at 2.8 GHz. The resonating patch contains five interconnected nested squares, including two square split ring resonators (SSRRs). The unit cell exhibits three distinct frequencies at 2.8 GHz, 5.8 GHz, and 11.2 GHz, with corresponding magnitudes of −45 dB, −50 dB, and −30 dB, respectively. Negative permittivity (ε-Negative) is observed in frequency ranges of 2.3–3.20 GHz, 4.4–6.9 GHz, and 10.8–11.30 GHz, with near-zero refractive index. The simulated outcome acquired in CST microwave studio is subsequently confirmed using analogous circuit modeling in Advanced System software (ADS). Moreover, the prototype of the proposed metamaterial is developed that shows similar resonances obtained in the simulation. The effective medium ratio (EMR) of the unit cell is calculated and a high EMR of 8.3 expresses the compactness of the metamaterial. Due to its structural compactness, this new metamaterial with ε-negative, near zero refractive index, and triple band resonance properties holds significant potential for wireless applications such as radar systems, satellite communications, and wireless sensor networks.

Design and development frequency reconfigurable microwave filter for wireless application

This paper presents a novel reconfigurable bandpass filter with three reconfigurable states used for C band wireless applications. The frequency reconfigurable is achieved using the combination of a different microstrip coupled resonator structure and switching device as PIN diodes. The open-loop filter structure provides three narrow band states at 5.1, 5.2, and 5.8 GHz. The frequency reconfiguration is obtained without compromising performances. The compact size of the proposed designed along with the targeted frequency bands at lower wireless local area network (WLAN) (5.1, 5.2 GHz), and worldwide interoperability for microwave access (WiMAX) (5.8 GHz) applications. The prototype is constructed on an RT duroid 5880 substrate and tested for validation in vector network analyzer (VNA). The designed filter provides excellent selectivity and good rejection at desired resonant frequencies.

High Isolation Quad-Element SWB-MIMO Antenna with Dual Band-Notch for ISM and WLAN Band Wireless Applications

A quad-element super-wideband (2-20GHz) MIMO antenna including dual notched-band response at WiMAX (3.30-3.70GHz) and satellite-band (6.99-8.09GHz) is designed on RO3035 with total dimension of 118mm×86mm×1.67mm. Unique decoupling structure has been deployed to enhance the isolation (˃20dB) between two antenna elements. The fundamental properties of MIMO antennas like bandwidth ratio (10:1), isolation (>18dB), gain (4.14dB), Envelop Correlation-Coefficient (<0.0065), Total Active Reflection-Coefficient (< 0dB), Channel Capacity Loss (<0.25bps/Hz) and radiation patterns are also investigated in order to determine their practicality. Measurement and simulation results of the proposed SWB-MIMO antenna from 2 to 20GHz indicate that it will be the suitable candidate for wireless and biomedical applications.

A symmetric plus-shape resonator based dual band perfect metamaterial absorber for Ku band Wireless Applications

In this article, introduce a metamaterial for microwave absorber applications based on a variant of the symmetric plus-shape resonator. This MA has two absorption peaks, making it suitable for Ku frequency band use. The MA unit cell built on a cheap FR4 substrate. The unit cell's resonator is designed in the form of a four-plus-shape with an eight-square-point in one of the corners, and its dimensions have been tweaked to achieve maximum absorption peaks of 99.04%, and 99.90% at 12.32 GHz, and 16.00 GHz, respectively. Analysing the surface current, electric and magnetic fields, permittivity, permeability, and normalised impedance provides insight into the nature of metamaterial and absorber. The incidence and polarization angle insensitivity of the suggested dual-band absorber allows for pretty much constant absorbance efficiency when the angle is changed. Moreover, for both TE mode and TM mode, the developed metamaterial absorber demonstrates near unity absorption for polarization and oblique incident angles up to 90°. These are single negative metamaterial qualities. The fact that the patch as a whole is rotationally symmetrical is one of the most important factors in determining whether or not it will retain its polarization-insensitive quality. Because of its outstanding insensitivity performance and nearly perfect absorption, it could be a good option for use in Ku band applications.

Half mode rectangular SIW slotted antenna for multiband operations using ANN optimization

AbstractA multiband half‐mode substrate integrated waveguide (HMSIW) slotted antenna is developed for ISM/WiMAX/WLAN applications. HMSIW technique has been utilized to acquire antenna compactness. Two inverted L‐shaped slots of half wavelength are embedded onto a HMSIW rectangular cavity for attaining a hybrid mode (i.e., Half‐mode of Half‐mode of ), which induces a lower resonance at 2.4 GHz. An inverted L‐shaped slot is influenced to radiate hybrid mode at 2.4 GHz, while the innermost inverted L‐shaped slot radiates modified mode at 3.30 GHz. A multiband is obtained by amalgamation of hybrid mode (at 2.4 GHz), modified mode (at 3.30 GHz) and modified mode (at 5.38 GHz). The radiating modes are elucidated by using mode theory methodology for ascertaining the resonance characteristics of the prototype antenna. The antenna parameters have been optimized by artificial neural network technique using MATLAB. The antenna geometry possesses a shrinkage size of 30 × 16 × 1.6 mm3, which has been designed on FR‐4 substrate. To vindicate the simulated consequence, the fabricated prototype has been tested. It contributes the fractional bandwidth of 6.4% (2.09−2.23 GHz) in the hybrid mode at 2.18 GHz, 9.03% (2.89−3.17 GHz) in the half cavity mode at 3.10 GHz and 9.96% (5.11−5.65 GHz) in the half cavity mode at 5.42 GHz, respectively, which is beneficial for ISM, WiMAX and WLAN band wireless applications.

A 4-element crescent shaped two-sided MIMO antenna for UWB, X and Ku band wireless applications

A 4-element crescent shaped two-sided MIMO antenna for UWB, X and Ku band wireless applications

A Typical Slotted SIW Cavity-backed Antenna for Dual frequency operations in U-NII Bands

A low profile circular shaped cavity-backed substrate integrated waveguide (SIW) antenna with two-typical intersecting rectangular slots on the ground plane is designed to operate in the dominant TM010 mode at a frequency of 5.19 GHz in U-NII-1 band for wireless applications. The initially designed antenna produces a gain of 4 dBi with a narrow impedance bandwidth extending from 5.17 – 5.22 GHz. The antenna design is further modified by insertion of another shifted two-typical intersecting rectangular slots to finally resemble that of Hash shape; resulting in dual band antenna operation at 4.9 and 5.93 GHz. The gains obtained are 3.7 dBi and 1.4 dBi for 4.9 and 5.93 GHz respectively with an impedance bandwidth covering 4.88 - 4.92 GHz and 5.92 – 5.94 GHz respectively. The antenna prototype is fabricated using Arlon AD270 substrate material. Parametric studies are performed in terms of return loss and gain of the antenna. All simulations are carried out using HFSS v19.0 and show similar behavior to their experimentally measured counterparts.

A Compact SE-DGS Tapered-Fed Notched UWB Antenna Integrated with Ku/K Band for Breast Cancer Detection

A compact and novel semi-elliptical defected ground structure (SE-DGS) tapered microstrip line fed UWB antenna with band-notched characteristics integrated with Ku and K band applications is proposed. The proposed SE-DGS UWB antenna is printed on a compact size of (15 × 18 mm2) and has radiation bandwidth of 25.66 GHz over a span of 4.11–29.77 GHz, a fractional bandwidth of 151.47%, and both the down link of X- and ITU-8 bands are completely notched over a span of 6.86–9.09 GHz using a single C-structured reflector. The proposed antenna has a fluctuating gain of 1.7–4.82 dBi except for the gain at the notched band frequency, which is −12.25 dBi. The proposed antenna has a high radiation efficiency of 96.23%, stable radiation patterns over the UWB range, and a high rejection capability of the notched band, which is noticed from the high value of VSWR of 23.15, making it a potential candidate for UWB, Ku, and K band wireless applications with effectively suppressed downlink of X and ITU-8 bands. The developed antenna design simulates breast cancer tissue detection by comparing S21 results, and specific absorption rates with and without tumour scenarios. These results suggest that the proposed radiator and system detect breast tumours efficiently.

Reconfigured antenna with switchable polarization for S Band Wireless applications

This article presents a polarization-switchable Microstrip Patch Antenna (MPA) that can be flexibly reconfigured. There are little parasitic patches connected to the corners of an MPA's circular patch as a radiator. The PIN diodes have made contact with O-shaped parasitic patch elements to form the circular patch. When the truncated corners are changed, enhanced the impedance bandwidth and axial ratio bandwidth has been obtained. 3.24 GHz is a resonant frequency for an impedance match (S11 less than 10dB) and for an axial ratio (AR less than 3 dB). The antenna's ability to transition between left- and right-handed circular polarizations (LHCP and RHCP) was verified by comparison of simulated and measured results observed. Vector Network Analyzer has also been used to evaluate the anticipated MPA under high RF strength in an anechoic room. Thus, the 5G networks and their related applications have been shown to work with these observed characteristics.

An Antipodal Antenna with Improved Axial Ratio Bandwidth

A circularly polarized (CP) slot antenna is implemented utilizing a Y-shaped radiating strip connected to a quarter wave microstrip feed line for better impedance matching. A parasitic strip, and an antipodal Y-shaped strip are used here to obtain wide axial ratio bandwidth. Utilizing of two optimized spring notches and a rectangular slit on the trapered slot ground plane enhanced circularly polarized radiation. The compact antenna (28 × 28 mm2; 0.277λ0 × 0.277λ0, λ0 is free space wavelength at 2.965 GHz) gives wide measured impedance bandwidth (IBW) from 2.965 to 13.461 GHz, center resonating frequency (fr ) 8.213 GHz, IBW 127.8% and a total of 10.496 GHz and measured wide CP band of 2.473 GHz (4.209–6.682 GHz, center CP resonating frequency (f cp) 5.445 GHz, 45.41%). The maximum measured peak gain of this antenna is 4.672 dBi at 6.5 GHz. Implemented antenna is suitable for some part of “S”, “C” and “X” band wireless communication applications.

Compact Quad Band MIMO Antenna Design with Enhanced Gain for Wireless Communications.

In this paper, a novel microstrip line-fed meander-line-based four-elements quad band Multiple Input and Multiple Output (MIMO) antenna is proposed with a gain enhancement technique. The proposed structure resonates at four bands simultaneously, that is, 1.23, 2.45, 3.5 and 4.9 GHz, which resemble GPS L2, Wi-Fi, Wi-MAX and WLAN wireless application bands, respectively. The unit element is extended to four elements MIMO antenna structure exhibiting isolation of more than 22 dB between the adjacent elements without disturbing the resonant frequencies. In order to enhance the gain, two orthogonal microstrip lines are incorporated between the antenna elements which result in significant gain improvement over all the four resonances. Furthermore, the diversity performance of the MIMO structure is analyzed. The Envelope Co-Relation Coefficient (ECC), Diversity Gain (DG), Channel Capacity Loss (CCL), Mean Effective Gain (MEG) and Multiplexing Efficiency are obtained as 0.003, 10 dB, 0.0025 bps/Hz, −3 dB (almost) and 0.64 (min.), respectively, which are competent and compatible with practical wireless applications. The Total Active Reflection Coefficient (TARC) resembles the characteristic of the individual antenna elements. The layout area of the overall MIMO antenna is 0.33 λ × 0.29 λ, where λ is the free-space wavelength corresponding to the lowest resonance. The advantage of the proposed structure has been assessed by comparing it with previously reported MIMO structures based on number of antenna elements, isolation, gain, CCL and compactness. A prototype of the proposed MIMO structure is fabricated, and the measured results are found to be aligned with the simulated results.

UWB Microstrip Patch Antenna with 5G Lower Band Notch Characteristics

For fifth generation (5G) lower band wireless application at a frequency of (4.5–5.5) GHz, recently ASEAN region countries have suggested 5G forums and band rejection antennas for 5G (4.5–5.5) GHz lower band. A UWB antenna has been constructed and suggested by use of the Roger RT5880 with defected ground on a rectangular radiating patch and a ring shape type of resonator (RSR) on ground plane to achieve the desired performance. It was decided to construct a band rejection within UWB antenna for 5G which included adding a rectangular slot on the radiating patch as well as placing RSR to the ground plane of the proposed antenna. The results support the theory that the antenna is capable of transmitting and receiving in the UWB except band notched bandwidth. Additionally, the results show that the antenna possesses good performance across the whole UWB spectrum with a gain of 4.6 dBi. This, in addition to its ability to support the lower 5G band notched, is why the suggested antenna is a good contender for future 5G wireless implementations within UWB bandwidth.

Meander and Koch Hybrid Fractal Curve Based Dual Hexagonal Radiating Patch Antenna for Quad Band Wireless Applications

A unique dual hexagonal-shaped radiating patch design with hybrid fractal curves (Meander and Koch) is presented for quad-band wireless applications. Initially, the antenna from 0th to 2nd iteration of hybrid fractal curves with PGP (Partial Ground Plane) is designed and investigated. Further, to get better results of the designed antenna in respect of Bandwidth (BW) and coefficient of reflection these hybrid curves are superimposed on the limited ground plane of 1st and 2nd iteration of the antenna and the generated antennas are designated as Antenna–1 and Antenna–2. A comparison between both the antennas has been made and it is observed that Antenna–2 shows better results in respect of improved BW and coefficient of reflection. The proposed antenna exhibits four resonant frequency bands 1.6, 4.8, 6.9, and 8.8 GHz with improved corresponding impedance BW of 2.09, 1.36, 0.86, and 1.51 GHz. The designed antenna is simulated and made on FR4 glass epoxy substrate with an overall size of 20 × 40 × 1.6 mm3. The fabricated proposed antenna is tested experimentally for the authentication of simulated results with experimental results and these are compatible with each other. The other performance indicators like radiation pattern, peak realized gain, and radiation efficiency are also determined for the proposed Hybrid Fractal Antenna (HFA) and all are found satisfactory. Due to the improved operational parameters, the designed HFA can be considered as a suitable applicant for distinct wireless applications in anticipated operational frequency ranges.

Rotational symmetry engineered, polarization and incident angle-insensitive, perfect metamaterial absorber for X and Ku band wireless applications

In this paper, a square enclosed split-maze shaped metamaterial absorber is proposed for X and Ku band wireless applications. Two square metal enclosures were introduced around the split-maze structure to make it rotational symmetric and thus insensitive to cross-polarization. The proposed absorber has shown maximum absorptions at 9.33 GHz, 12.83 GHz, 13.86 GHz, and 15.61 GHz with single negative value of permittivity. The absorber is insensitive to the incident angle of applied EM waves for normal and oblique incidence up to 180 degrees. In addition, it was proved co- & cross-polarization insensitive due to the symmetric structure of the patch. A comprehensive equivalent circuit analysis was done to explain the fundamental EM behaviour of the metamaterial structure, and the circuit outputs coincided with the simulation results. Finally, the metamaterial was measured for both unit cell, and the array after fabrication and simulation results were validated. The proposed MMA is suitable for wireless applications in devices, especially for sensing, EM energy harvesting, EM coupling reduction, and antenna gain enhancement purposes.

Dodecagon-Shaped Frequency Reconfigurable Antenna Practically Loaded with 3-Delta Structures for ISM Band and Wireless Applications

An edge fed, dual band, quarter-wave transformer coupled, monopole, ultra-wideband (UWB), dodecagon-shaped miniaturized frequency reconfigurable antenna for ISM and wireless applications is designed, analysed and investigated. The impedance transformer is utilized in the structure for impedance matching and hence results in lower reflection coefficient values. The antenna uses defected ground structure (DGS) in the bottom and radiating patch that is practically loaded with three numbers of delta structures. The use of DGS reduces the value of gain and provides ultra-wideband bandwidth across the designed frequency. The addition of three delta structures in the patch improves the value of gain. Miniaturizing in the size of the antenna has been achieved by reducing the ground along the width that led to a total 30.41% size reduction in the fundamental circular patch antenna. The antenna exhibits two bands 1.82–3.61 GHz and 5.24–12.43 GHz thus antenna is suitable for ISM band, PCS, 5G, Wi-Fi/WiMAX/WLAN and other wireless applications. The fabricated antenna is frequency reconfigured by utilizing the switching property of four numbers of PIN diodes (BAP64-02V). Frequency reconfigurable antenna is used flexibly and versatile for various microwave applications based on the switching conditions (more than eight digital combination cases) of PIN diodes. The prototype measured results provide good agreements with the simulated reflection coefficients values in some mode of operations. Antenna radiating patch and ground is etched on FR-4 substrate of dimension 52 mm × 59 mm × 1.6 mm using printed circuit board technology.

Efficient Microstrip Antenna system using Reduced GP Structure for Ultra-Wide Band (UWB) Applications

Microstrip antenna is an essential choice for Ultra Wide Band (UWB) applications of its light weight, low profile and easy to form antenna arrays. However, the design of microstrip patch antenna bandwidth is greatly affects by the dielectric substrate material (FR4). In this research, the bandwidth enhancement of MPA was designed by minimizing the dimension of Defected GP (DGP) in GP for Ultra Wide Band wireless applications. But, the antenna design complexity increases with the number of an operating frequency band. In this research, the MPA was designed as small as size of 10×13×1.6 mm and operates on frequency band between 3.1GHz to 10.6GHz for VSWR less than 2. The microstrip patch antenna was designed at 3.1GHz to 10.6GHz using High-Frequency Structure Simulator (HFSS) software. The simulation result shows that the proposed microstrip patch antenna obtained <-10dB of return loss from 3.1GHz to 10.6GHz throughout the frequency range. The measured result proves that the proposed microstrip patch antenna has better characteristics to fulfill the requirements of UWB applications

A frequency and polarization reconfigurable L shaped patch antenna with defected ground structure

A novel geometry of polarization and frequency reconfigurable antenna is proposed in this paper. Proposed antenna consists of an L shaped patch antenna, where arms are separated using PIN-diode. Two parasitic elements, shorted back element and edge tapered defected ground structure with slot are used for achieving wide impedance and axial ratio bandwidth. It acts as circular polarized antenna with 1.183 GHz axial ratio band width and 3.09 GHz impedance bandwidth in ON state of both diodes and act as linear polarized frequency reconfigurable antenna at remaining states of diodes. Proposed antenna can be used in C band wireless applications like RADAR, satellite communication etc.

Dual port spiral shaped dielectric resonator MIMO antenna with orthogonal modes for wideband application

In this article, Dual port excitation spiral shaped dielectric resonator multiple input multiple output (MIMO) antenna is explored for wideband application. Dual coaxial feeding in inner and outer edge of spiral geometry generates orthogonal hybrid modes. Merging of various hybrid modes lead to a wide bandwidth of operation. HE 11 δ x , HE 11 δ y and HE 12 δ x , HE 12 δ y orthogonal radiating modes are investigated at 8.7 GHz and 11 GHz resonant frequencies, respectively. Proposed antenna covers wide operating frequency range from 8–15.1 GHz to 7.8–14.6 GHz corresponding to excitation of Port-1 and Port-2, respectively, is achieved between ports. Isolation below −25 dB. Envelope correlation coefficient, diversity gain, Total active reflection coefficient, radiation pattern, channel capacity loss, gain, efficiency and various other characteristics of MIMO antenna are explored. This antenna can be used for various C and X band wireless applications.

A CPW-fed rectangular nested loop antenna for penta band wireless applications

A miniaturized coplanar waveguide (CPW) fed rectangular nested loop antenna is proposed for penta band wireless applications. Multiband and antenna compactness are obtained by using rectangular loop resonators. The proposed antenna has been optimized by increasing the number of loop iterations. The designed antenna comprises four rectangular loops, it constructs the antenna to excite 1.01 GHz, 1.67 GHz, 2.30 GHz, 2.92 GHz and 3.48 GHz frequency bands. The fabricated geometry has a dimension of 30 × 30 × 1.6 mm3, which is developed on a low-cost Flame Retardant-4 substrate having εr = 4.4 and tanδ = 0.02. The resonance behavior of the proposed antenna is verified by employing LC quasi-static design equations. The measured reflection coefficient and far-field pattern are exhibited to support the performance of the designed antenna for wireless applications.