Radiating Patch Element Research Articles

Design and performance observation of U-shapedQuadpot multiband operated MIMO antenna structure for 5G and WLAN applications using FR4 substrate with high isolation

The multiband operated four port MIMO antenna structure is presented in the manuscript. The unique U-shaped radiating patch element is considered for the analysis. Multiple iterations are taken to finalize the shape of the best structure. The DGS and parasitic patch approach helps enhance MIMO antenna performance. Four parametric studies are performed to find the best structure, varying the patch's length, breadth, parasitic patch radius and DGS. The analysis of scattering response is considered to be over 1 GHz to 14 GHz for the observation of band response. The suggested design represents a reflection coefficient of −38.092 dB and a peak bandwidth of 5.78 GHz. The proposed design provides a peak isolation of 60 dB and a peak E-field of 1.80 × 104 V/m. Using an FR4 substrate, the structure's response is compared with the simulated and measured. The effectiveness of the MIMO structure is checked by observing the performance of diversity parameters. The ECC value is near zero, the Negative value of TARC, the CCL is less than 0.08, the DG is near 10 dB and the MEG value is zero. The response of all diversity parameters is within the allowable range. The presented design opens a new way to target 5G and WLAN-related applications.

A New Sum-Channel Radiating Element for a Patch-Monopole Monopulse Feed

This article describes a new design for the sum-channel, circularly-polarized, radiating patch element of a multimode patch-monopole monopulse feed. Such feeds are suitable for the prime-focus illumination of a deep symmetric reflector. A relatively simple and compact feed design allows for a compact single-mirror antenna with monopulse tracking. The feed is about a wavelength in diameter, also making it suitable for illuminating smaller antennas, for example, in LEO-satellite ground (client) stations. The design applies a slotted circular patch as a circularly-polarized sum-channel element. The design variables are optimized mainly for the sum-channel aperture illumination efficiency in an S-band satellite ground station. After a few cut-and-try iterations, the final feed prototype was produced and measured. In addition to an additional degree of freedom in the geometry and potentially easier fabrication, the new sum-channel radiating-element shape allows for a slightly better monopulse channel isolation, and a higher radiation-pattern symmetry compared to the previous design.

Design and diversity performance analysis of C shape engraved miniaturised, and high gain Quad-Port MIMO antenna for 5 G and P2P communication

The 4-Port multiband operated MIMO antenna operating at 4 GHz, 6 GHz and 9 GHz is proposed to target the 5 G and P2P communication applications. The electrical size of the 4-Port antenna structure is 0.8λ × 0.48λ. The unique shape of a single radiating patch element is identified by engraving a circular shape patch element and modifying the shape of the feedline. The optimisation in terms of return loss was achieved based on the defected ground structure and changing radius of different elements of the patch structure. The 2-Port and 4-Port MIMO antenna structures are designed using the FR4 substrate and their return loss is compared and examined. The proposed design provides a minimum return loss of −22 dB, peak bandwidth of 2.25 GHz, peak gain of 4.67 dB, and normalised directivity of 187°. Different MIMO diversity parameters are analysed. The proposed design provides an envelope correlation coefficient of 0.01, Diversity gain near 10 dB, mean effective gain of almost zero, channel capacity loss of almost zero and Mean effective gain within the acceptable range. The overall Performance of the Proposed Design is compared with other 4-Port design structures and it represents healthy gain, multiple band response and proper diversity parameters making it suitable for the 5 G and P2P communication applications.

A Frequency-Selective Reconfigurable Antenna for Wireless Applications in the S and C Bands.

This paper presents a compact multifrequency reconfigurable patch antenna in terms of design and fabrication for operating in the S and C bands of the RF spectrum, which are overwhelmed by wireless applications. Reconfiguration is achieved by using a single PIN diode on the ground plane. By varying the voltage applied to the diode, three modes can emerge, exhibiting main resonant frequencies at 2.07, 4.63, and 6.22 GHz. Resonance switching requires a voltage of less than 0.9 V. The antenna fabricated on an FR-4 substrate, with a volume of 70 × 60 × 1.5 mm3, has a radiating patch element of a rectangular ring shape. The proposed low-cost antenna is easily implemented in a typical university lab-based environment. The total bandwidth for the three modes is close to 1 GHz, while the voltage standing wave ratio (VSWR) of the fabricated version of the antenna does not exceed 1.02, and the return loss is well below -40 dB for the three primary resonant frequencies.

Miniaturized and high gain circularly slotted 4×4 MIMO antenna with diversity performance analysis for 5G/Wi-Fi/WLAN wireless communication applications

A miniaturized with a high gain four port Multiple-Input Multiple-Output (MIMO) is presented in the manuscript. The presented design contains four radiating patch elements with a Defected Ground Structure (DGS). The shape of the radiating element is identified after the analysis of three stages. The design optimization is performed by changing the diameter of the circle loaded in the patch region and changing the length of the ground layer. The design is investigated for L, S, C, and X frequency band regions. The structure is designed using flame-retardant glass-reinforced epoxy laminate material (FR4) substrate material. The physical size of the four-port structure is 78x50 mm2. Three resonating frequency bands are observed at 2.02 GHz, 5.87 GHz and 11.19 GHz. The structure provides minimum return loss of −10.27 dB, −18.51 dB and −18.59 dB. The proposed design achieves a peak bandwidth of 3.94 GHz, and a maximum gain of 10.03 dBi, Various diversity parameters, including Total active reflection coefficient (TARC), Envelope Correlation Coefficient (ECC), mean effective gain (MEG), Diversity Gain (DG), and channel capacity loss (CCL), have been thoroughly analyzed. The measured and simulated outcomes are compared and analyzed. All performance indicators meet the allowed limits, demonstrating the suitability of the design for 5G, Wi-Fi and WLAN wireless communication applications.

A dual operating (27/38 GHz) high performance 2 × 4 MIMO antenna array for 5G new radio applications

This article presents an unique configuration of Multiple-Input Multiple-Output (MIMO) antenna array for functioning at 27/38 GHz millimeter-wave 5G new radio (NR) frequency bands applications. The suggested antenna is constructed with four MIMO elements, containing total of eight identical patches arranged in a 2 × 4 array configuration. The array also includes a separate non-connected rectangular ground plane with an overall dimension of 32.4 × 32.8 × 0.8 mm3. The single radiating patch elements are designed using spline resonator with H-shaped structures. The prototype model is realized using low cost FR-4 substrate and the obtained measurement results validate the analyzed simulated results. The suggested MIMO array antenna offers dual band operation with an impedance bandwidth of 8400 MHz covering 22 to 30.4 GHz and 8500 MHz ranging from 36.1 to 44.6 GHz. The proposed antenna achieves a peak gain of 8.75 dBi when operating at 27 GHz and 18.59 dBi at 38.1 GHz. Furthermore, it shows circular polarization characteristics by offering the axial ratio values significantly lower than 3 dB at 27 GHz and 38.1 GHz frequency bands. Additionally, the results indicate the favourable values of the diversity performance parameters with reference to Mean effective gain (MEG), Envelope correlation coefficient (ECC), Diversity gain (DG), Total active reflection coefficient (TARC), and Channel capacity loss (CCL). Moreover, it demonstrates high isolation (<−20 dB) within the desired bandwidth. These superior characteristics make it compatible for 5G NR frequency bands N257(26.5-29.5 GHz), N258 (24.5-27.5 GHz), N259 (39.5-43.5 GHz) and N260 (37-40 GHz), enabling its use in various countries including the China, European Union, Sweden, Korea, Japan, United States of America, Canada and Australia.

An LTCC-Based Antenna Array for D-Band Terahertz Communication

<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> </i> — In this letter, a novel patch antenna array with via and slot loading based on low-loss substrate integrated waveguide (SIW) feeding network is investigated for D-band applications. The radiating patch element is designed with vias and modified geometry for good broadband impedance matching response and high radiation gain. The feeding network provides the same magnitude and in-phase excitation for the radiating elements in the array. To verify the proposed array design, a 4×4 array prototype is implemented by low-temperature co-fired ceramic (LTCC) fabrication method and tested. The proposed dual resonance concept is validated by the good agreement between the simulated and measured results. The measurement results of the fabricated prototype show that the proposed design can achieve an 12.5% 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 (150 to 170 GHz) and realize a maximum gain of 16.8 dBi at 166 GHz. With the combined advantages of wideband, low fabrication difficulty and stable broadside radiation, the proposed array antenna is considered as a promising candidate for future D-band terahertz phased array communication.

Sprocket gear wheel shaped printed monopole ultra‐wideband antenna with band notch characteristics: Design and measurement

A compact ultra-wideband (UWB) printed monopole UWB with dual band-notched characteristics has been designed and investigated in this manuscript. The Wi-MAX and wireless local area network (WLAN) band rejection characteristics have been obtained by employing the circular ring and arc-shaped slot along with rectangular slot in radiating patch. Overall size of proposed UWB antenna is 27 × 27 × 1.6 mm3, which consists of sprocket gear wheel shaped structure as a core radiating patch element and excited by using 50 Ω coplanar waveguide feed. The proposed antenna exhibits the UWB frequency spectrum from 3.1 to 10.6 GHz along with Bluetooth frequency range 2.4–2.48 GHz without disturbing overall dimensions of antenna. Proposed antenna reveals the measured VSWR operating bandwidth of 10.0 GHz in the frequency range from 2.0 to 12.0 GHz along with Wi-MAX and WLAN rejected bands. Moreover, proposed antenna adorns the measured gain of −8.28 and − 9.98 dBi at rejected frequency bands, whereas, at other frequencies, it changes between 1.5 and 5.0 dBi. The radiation efficiency of proposed UWB antenna varies from 84% to 97% except rejected frequency bands. Group delay and radiation pattern have also been analyzed and found appropriate for the current UWB applications. Finally, the optimized structure of antenna with dual band rejection characteristics has been fabricated and tested for the authentication of simulated results. Both the results are compared and are found in good agreement with each other.

Design of a high-gain dual-band antipodal Vivaldi antenna array for 5G communications

AbstractThis paper presents a dual-band 1 × 4 antipodal Vivaldi antenna (AVA) array with high gain to operate over a dual-frequency band that covers the 5G frequency spectrum. The gain is enhanced by employing a dielectric lens (DL). The AVA array consists of four radiating patch elements, corrugations, DL, and array feeding network on the top side. The bottom side contains four radiating patches which are the mirror images of top radiating patches. The designed AVA contains 1 × 4 array antenna elements with a DL that is operating in the ranges of 24.59–24.98 and 27.06–29 GHz. The dimensions of the designed antenna are 97.2 mm × 71.2 mm × 0.8 mm. For the improvement in gain and impedance matching at the dual-band frequency, corrugation and feeding network techniques are used. The gain obtained is about 8–12 dBi. AVA array is tested after fabrication and the measured results are reliable with the simulation results.

MIMO Dual Sensing Antenna with Notch Characteristics

Design of MIMO antenna with having notch band characteristics between 2.5 GHz-3.7 GHz and 7.7 GHz-8. 6 GHz in the Ultra-wide band operating range from 2.3 GHz-9.96 GHz. For getting notch bands in UWB frequency bands, parallel stubs are kept in the ground to separate the radiating patch elements. The parallel stubs placed in the ground plane improved isolation to 18 dB. The ECC less than 0.01 at the frequency band and the DG is close to 9.5 dB. As the antenna is designed on the flexible polyimide substrate it undergone for bending analysis for different angles like 300,600 and 900. The prototyped antenna measured results providing good agreement with the simulated once obtained from commercial HFSS tool. The obtained band notching characteristics will object some of the frequency applications like WLAN, WiMAX and X-band satellite communication.

Circularly-polarized linear antenna array of non-identical radiating patch elements for WiFi/WLAN applications

Here we present a novel linear circularly polarized (CP) antenna array using non-identical CP elements, where the Chinese character-shaped patches are employed to form a linear array. Namely, the single-feed CP Zhong-, Guo-, and Meng-shaped patch antennas have collected to form a three-element antenna array. A one-to-three power splitter with equal amplitudes but unequal phase-shifts at its output ports was deliberated as the feed network for the linear array. The challenge of this antenna array design is the appropriate phase excitation to the non-identical radiating elements so that the CP gain and operating bandwidth can meet the requirements of the application(s), in which we undertook an in-depth investigation. A proof-of-concept design example for 2.4 GHz wireless local area network (WLAN, IEEE 802.11b/g/n) has demonstrated the effectiveness of the combination technique on the non-identical CP antenna elements. The simulation, in combination with experimental validation, obtained an on-axis 3-dB axial-ratio bandwidth from 2.28 to 2.59 GHz (12.7%), whereas a broadside gain of 9 dBic at 2.5 GHz and an overall efficiency of 82% were recorded within the bandwidth.

Analysis, Design and Fabrication of a Square Slot Loaded (SSL) Millimeter-Wave Patch Antenna Array for 5G Applications

A new compact [Formula: see text] microstrip patch antenna array design for future 5G applications is presented in this paper. The proposed antenna array consists of square slot loaded with four radiating patch elements. The corporate feed network has been implemented for the excitation of the array. The feed line is connected to the square slot patch through a quarter-wave transformer matching network. The proposed array is designed on an FR-4 substrate with a dielectric constant of 4.4, thickness of 1.6[Formula: see text]mm and loss tangent (tan[Formula: see text] of 0.02. It has a compact dimension of 9.590[Formula: see text] 17.802[Formula: see text]. The proposed structure has been designed and simulated by using commercially available HFSS software. The simulated results (reflection coefficient, gain, efficiency, radiation pattern) are verified through the measurement process to confirm the validity of the design concept. The measurement results are in good agreement with the simulated results. The proposed structure resonates at 38.1[Formula: see text]GHz with a [Formula: see text]10[Formula: see text]dB impedance bandwidth of about 3700[Formula: see text]MHz (36.5[Formula: see text]GHz to 40.2[Formula: see text]GHz). The reflection coefficient at 38.1[Formula: see text]GHz is [Formula: see text]34[Formula: see text]dB, with a maximum gain of 7.81[Formula: see text]dB. The proposed square slot loaded patch antenna array is very promising for 5G communications at 38[Formula: see text]GHz band (37–40[Formula: see text]GHz).

Circularly Polarized Retrodirective Antenna Array for Wireless Power Transmission

A retrodirective antenna (RDA) array for wireless power transmission (WPT) is presented. Applications include the wireless charging of mobile phones and other handheld devices. The reported RDA defines an active high-power transmitter module that retrodirects a received beacon tone back to a mobile unit by circularly polarized (CP) free-space radiation. In addition, this RDA architecture uses a network of four subarrays, defined by a total of 16 radiating patch elements, in an effort to boost the transmit gain while also reducing the supporting RF hardware requirements when compared to a more conventional RDA. Measurements and simulations in the reactive near-field of the system are in agreement in terms of the tracking capabilities of the high-power CP-RDA. Power levels in excess of 27 dBm were measured at 2.4 GHz at a receiver module, and when this RF power was rectified, more than 350 mW at dc was observed. To the best knowledge of the authors, this is the first demonstration of a WPT system using a mixer-based analog RDA. Previous low-power demonstrations were more complex computer-controlled systems that did not offer any real-time tracking ability. Other applications for the proposed RDA include target tracking, sensor charging, and other WPT systems.

Design and analysis of aperture coupled micro strip patch antenna for radar applications

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, 4.5 ​dB directivity, efficiency of 30%, impedance bandwidth of above 15% higher than inset feed line with 1.5 ​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.

Compact Self Complementary UWB Antenna with Triple Band Notch Characteristics for Wireless Communications

the objective of this paper is to design and analysis of the Ultra wide Band Micro strip Patch Antenna which covers the Ultra Wide Band 2.9 to 21.5 GHz. To get an optimum results and performance of the projected self complementary UWB antenna depends on the study of dissimilar methods for optimizing the different parameters of the radiating patch along with notch dimensions. The proposed self complementary UWB antenna with overlapped rectangular shape patch and Defected DGS is designed with C-Slot in the radiating patch element and ground with L shaped slot which covers the whole UWB frequency band apart from band notches WLAN (5.125-5.825 GHz) ,Satellite Communications (7.9-8.5 GHz) and Ku band 13.4-14.5GHz.The UWB antenna performance is improved in terms of the Bandwidth by including Rectangular shaped slit between feeding element and the radiating patch. Now a days it is important to avoid existing wireless communication networks from the design of UWB antenna. The self complementary UWB antenna impedance bandwidth from 2.9 GHz to 21.5 GHz with a maximum of return loss S11 -43 dB at operating frequency10.5 GHz and with a Gain of 5.64dB.

Design of crescent slot circularly polarised patch for 4G wireless communications

A single fed circularly polarised patch antenna operating at 4G long term evolution (LTE) is proposed. The antenna is excited by means of 50 Ω coaxial cable placed near to edge of the patch element. In order to achieve circular polarisation, a crescent-shaped slot is incorporated in the radiating element which perturbs the surface current fields on the radiating patch element. Based on the slot orientation, the antenna radiates either left-hand or right-hand polarisation. The shape of the crescent slot and position of feed point are tuned to improve 3db axial ratio beam width of the antenna. The antenna parameters are characterised using Ansoft high frequency structure simulator and further, parametric analysis on antenna dimensions are carried and its effects on antenna performance are discussed. The antenna attains −10 dB impedance bandwidth (2.55 GHz to 2.6 GHz) in the 4G band and achieves a return loss of −16.06 dB with a peak gain of 5.94 dB at its operating frequency. The antenna also achieves wider axial ratio (AR) beam width of 1050 (AR ≤ −3 dB) and good cross-polarisation isolation of −17.93 dB which makes it more suitable for modern wireless communications.

A Compact Ultrawideband Antenna Based on Hexagonal Split-Ring Resonator for pH Sensor Application.

A compact ultrawideband (UWB) antenna based on a hexagonal split-ring resonator (HSRR) is presented in this paper for sensing the pH factor. The modified HSRR is a new concept regarding the conventional square split-ring resonator (SSRR). Two HSRRs are interconnected with a strip line and a split in one HSRR is introduced to increase the electrical length and coupling effect. The presented UWB antenna consists of three unit cells on top of the radiating patch element. This combination of UWB antenna and HSRR gives double-negative characteristics which increase the sensitivity of the UWB antenna for the pH sensor. The proposed ultrawideband antenna metamaterial sensor was designed and fabricated on FR-4 substrate. The electrical length of the proposed metamaterial antenna sensor is 0.238 × 0.194 × 0.016 λ, where λ is the lowest frequency of 3 GHz. The fractional bandwidth and bandwidth dimension ratio were achieved with the metamaterial-inspired antenna as 146.91% and 3183.05, respectively. The operating frequency of this antenna sensor covers the bandwidth of 17 GHz, starting from 3 to 20 GHz with a realized gain of 3.88 dB. The proposed HSRR-based ultrawideband antenna sensor is found to reach high gain and bandwidth while maintaining the smallest electrical size, a highly desired property for pH-sensing applications.

Wide‐band circularly polarised antenna array using sequential phase feed structure and reinforced square radiating patch element

A $2 \times 2$2×2 circularly polarised (CP) antenna array with four square radiating patch elements has been introduced here. The array elements are sequentially rotated and have been fed by a simple single-layer feeding network with sequential phase structure. This feeding network generates successive phase difference at its four outputs. To have a wide CP bandwidth, the proposed method of feeding network has been combined with new simple tuning stubs which are embedded in radiating patch elements. The common reflection coefficient bandwidth ($S_{11} \lt - 10\, {\rm dB}$S11<;-10 dB) and axial ratio (AR) bandwidth (AR <;3 dB) is 1000 MHz which covers 1.5-2.5 GHz frequency band and according to the centre frequency of 1.8 GHz, the frequency bandwidth is ~55.5%. Furthermore, the peak gain of the proposed antenna array is ~7.5 dBi at the frequency range of 1.7-2.3 GHz.

Millimetre‐wave T‐shaped MIMO antenna with defected ground structures for 5G cellular networks

In this study, a millimetre-wave (MMW) antenna is presented for the fifth-generation (5G) wireless multiple-input multiple-output (MIMO) applications, in order to offer numerous advantages including compactness, planar geometry, high bandwidth, and high gain performance. The concept of defected ground structures has been deployed for the first time in MIMO antenna design at MMW spectrum to fulfil 5G requirements of high bandwidth with compactness and low design complexity. The top surface of antenna comprises of a coplanar waveguide-fed T-shaped radiating patch element, while the bottom part is designed to constitute a partial ground loaded with two iterations of symmetrical split-ring slots at an optimised distance. Experimental results depict a wide bandwidth of 25.1-37.5 GHz, as well as a peak gain of 10.6 dBi at 36 GHz. Moreover, numerically evaluated efficiency of >80% is observed over the entire intended bandwidth of operation. For the demonstration, four-element MIMO antenna array of the proposed antenna element is also fabricated and tested, in order to validate high isolation between the adjacent elements, which makes the proposed antenna a potential candidate to be integrated in cellular phones and base stations for 5G MIMO systems and services.

Broadband circularly polarized patch antenna with low crosspolarization using artificial ground structure

AbstractThis letter proposes a circularly polarized patch antenna with 3‐dB AR (axial ratio) and reasonably constant gain characteristics and low crosspolarization covering a wide bandwidth using an AGS (artificial ground structure). The AGS with a rectangular unit cell can expand the 3‐dB axial ratio of CP (circular polarization) and impedance characteristics of circularly polarized patch antennas. For achieving the broadband impedance characteristics, a matching structure is required to keep a sufficient impedance bandwidth between the two parallel resonances separated with a large ratio of frequency. As the matching structure, the outer conductor of a feeding coaxial cable passing through the ground plane is extended to be close to the radiating patch element. However, such matching structure yields large XPOL (crosspolarization) in off‐boresight directions. In this letter, the extended coaxial structure is replaced with a meandering probe for suppressing XPOL and matching impedance. The effect of the meandering probe is discussed with simulated and measured results. As a result, the proposed structure achieves a −10‐dB S11 bandwidth of around 50% and a 3‐dB AR bandwidth of 20%, respectively. The average gain of 7.8 dBic is achieved covering the AR bandwidth. Furthermore, off‐boresight XPOL decreases by around 10 dB compared to the previous structure with the extended coaxial structure in ±30° directions.