Rectangular Patch Antenna Research Articles

Study on received signal strength of femtocell with circular and rectangular microstrip patch antenna designed at 2.55 GHz

In large cities, the coverage and quality of telecommunication services inside buildings is low and needs more effort for its improvement. Signal attenuators like number of walls, number of floors and others affect the quality of received signal. Therefore, femtocells are used for improving the poor performance of network inside buildings and other dead zone areas. The aim of this work is to compare the received signal strength of femtocell with rectangular and circular microstrip patch antenna designed at 2.55 GHz. This work considers the received signal strength of femtocell with the designed rectangular and circular microstrip patch antennas. The performance analysis uses Multi Wall Multi Floor indoor propagation model. The result showed that the total gain of rectangular and circular microstrip patch antenna are 3.6528 dB and 2.924 dB, respectively. The received signal strength of femtocell with rectangular microstrip patch antenna is larger than that of circular microstrip patch antenna designed at the same frequency. The effect of number of walls and floors on the received signal strength of femtocell is also clearly indicated. Generally, it is found that much higher received signal strength is observed in rectangular microstrip patch antenna than in circular one. The outcome of this work shows that femtocells are capable of enhancing signal quality for indoor users.

Bandwidth enhancement of dual-band bi-directional microstrip antenna using complementary split ring resonator with defected structure for 3/5 GHz applications

<span>This paper presents a bandwidth enhancement of a dual-band bi-directional rectangular microstrip patch antenna. The novelty of this work lies in the modification of conventional rectangular microstip patch antenna by using the combination of two techniques: a complementary split ring resonator (CSRR) and a defected patch structure (DPS). The structure of antenna was studied and investigated via computer </span><span>simulation technology (CST). The dimension and position of CSRR on the ground plane was optimized to achieve dual bandwidth and bi-directional radiation pattern characteristics. In addition, the bandwidths were enhanced by defecting suitable shape incorporated in the microstrip patch. A prototype with overall dimension of 70.45×63.73 mm<sup>2</sup> has been fabricated on FR-4 substrate. To verify the proposed design, the impedance bandwidth, gain, and radiation patterns were carried out in measurements. The measured impedance bandwidths were respectively 560 MHz (3.08-3.64 GHz) and 950 GHz (4.64-5.59 GHz) while the measured gains of each bandwidth were respectively 4.28 dBi and 4.63 dBi. The measured radiation patterns were in good agreement with simulated ones. The proposed antenna achieves wide dual bandwidth and bi-directional radiation patterns performances. Consequently, it is a promising candidate for Wi-Fi or 5G communications in specific areas such as tunnel, corridor, or transit and rail.</span>

Analysis of multiband rectangular patch antenna with defected ground structure using reflection coefficient measurement

<p class="Abstract">In this paper, a novel quad band antenna to operate at four different frequency bands is designed and simulated using Computer Simulation Technology (CST) Microwave Studio software. To achieve better performance of the antenna, various parameters were optimized using parametric analysis. During this analysis, various antenna parameters were need to be measured. The proposed antenna uses asymmetrical ‘U’ and ‘T’ shaped radiating elements printed on an FR-4 substrate with dimensions of 1.6 × 34 × 20 mm<sup>3</sup>. The measurement of various antenna parameters like reflection coefficient, return loss, radiation intensity are key tasks to be performed in the antenna measurement laboratory before going to the real time application. A stair case defected ground structure with rectangular center slot is used to attain a better bandwidth. The antenna resonates at four different frequencies 3 GHz, 4.8 GHz, 9 GHz, 13.2 GHz with operating bandwidths of 980 MHz, 2.05 GHz, 3.84 GHz, and 3.82 GHz respectively. The S<sub>11</sub> value at these resonant frequencies is measured as -23.6 dB, -29.4 dB, -34.2 dB, -49.05 dB respectively. The voltage standing wave ratio of the proposed antenna at four resonant frequencies is equal to one. The gain of the antenna is consistent throughout the four pass bands. The antenna is suitable for Bluetooth (2.4) GHz, WLAN (5.125-5.35) GHz and (5.725-5.825) GHz, WiMAX (5.25-5.85) GHz, C-band (3.7-4.2) GHz and Ku-band (12-18) GHz.</p>

Effect of Dielectric Cover Thickness Analysis on Rectangular Microstrip Patch Antenna in Wi-Fi Applications

This paper studies the effect of dielectric covers or superstrate with different thickness on rectangular microstrip patch antenna. The proposed antenna is designed at 2.4GHzfrequency using method of transmission line model. The dielectric covers or superstrates are providing protection to the antenna from different environmental hazards conditions. The HFSS electromagnetic simulation software is used for simulating the antenna using different dielectric superstrate covers. The different cover thickness affects is investigated on microstrip antenna and compared their performance with and without superstrates.

W-shaped slot-loaded U-shaped low SAR patch antenna for microwave-based malignant tissue detection system

This paper describes a wideband W-shaped slot-loaded solid U-shaped rectangular patch antenna for a microwave-based head imaging application. The proposed antenna comprises a W-shaped slot-loaded solid U-shaped radiating patch and a slotted partial ground. Slots have been used to enhance efficiency, current distribution, gain, and other antenna performances. At its first resonance frequency of 1.6 GHz, the optimized electrical dimension is 0.197λ × 0.298λ × 0.085λ. The antenna is printed on a low-cost 1.6 mm-thick FR4 substrate. The antenna feeds with a 50 Ω transmission line. The assessed findings demonstrated that the stated prototype has a 1.12 GHz (1.40 - 2.52 GHz) bandwidth along with omnidirectional radiation properties. The prototype achieved a maximum gain of 3.5 dBi at 2.44 GHz and provided a maximum radiation efficiency of 95% with stable radiation characteristics. The face-to-face alignment fidelity factor (FF) is also determined to evaluate time-domain responses above 80%. Near field directivity (NFD) is also analyzed with a head model to ensure near field radiation characteristics. The SAR value reaches a < 0.3 W/kg limit over the active bandwidth. Finally, in a CST simulation platform, an array configuration with nine antenna elements is deployed in a circular arrangement around the head phantom to collect the scattered data for tumor object characterization.

Design of circularly polarized flat‐top pattern with phase gradient metasurface

This article presents a metasurface (MTS) for designing a circular polarized (CP) flat-top radiation pattern using the phase compensation method. The basic idea is to generate multiple beams pointing in different directions by dividing the entire MTS into sub-regions. The MTS consists of four-layered elliptical patches encircled in a square loop printed on three dielectric substrates. The asymmetric nature of the unitcell produces two orthogonal components with equal magnitude and 90° phase difference to obtain the required linear to circular polarization conversion. The proposed MTS consists of 15 × 15 unitcells, and is fed by a rectangular patch antenna operating at 10 GHz. The flat-top pattern has been observed in the 3-D plane for u,v-polarized wave incidences at 9.9 GHz. For u-polarized incidence wave results in left-hand circular polarized (LHCP) flat-top radiation pattern with a 1 dB beamwidth of 37.5°. The axial ratio is less than 3 dB in all planes within the 1-dB beamwidth at 9.9 GHz. Similarly, for v-polarized incident wave, identical characteristics have been observed for right-hand circular polarization (RHCP), which enables the proposed structure for polarization diversity.

Analysis Method of Bending Effect on Transmission Characteristics of Ultra-Low-Profile Rectangular Microstrip Antenna.

With the advent of wearable communication devices, microstrip antennas have developed multiple applications due to their ultra-low-profile properties. Therefore, it is essential to analyze the problem of frequency shift and impedance mismatch when the antenna is bent. For the case of a rectangular patch antenna E-plane bent on the cylindrical surface, (1) this paper introduces the effective dielectric constant into the cavity model, which can accurately predict the resonance frequency of the antenna, and (2) according to the equivalent circuit model of the antenna resonance mode, the lumped element parameters are calculated based on the above effective dielectric constant, so that impedance characteristics and the S-parameter matching the port can be quickly constructed. From the perspective of circuit frequency characteristics, it explains the change in the transmission performance of the curved antenna. The experimental results show that the maximum difference between the experimental and theoretical calculation frequencies is less than 1%. These results verify the validity and applicability of the theory in the analysis of ultra-low-profile patch antennas and wearable electronic communication devices. It provides a theoretical basis for the fast impedance matching of patch antennas under different working conditions.

Broadband high gain cavity resonator antenna using planar electromagnetic bandgap (EBG) superstrate

AbstractThis paper presents a broadband miniaturized Fabry–Perot cavity resonator antenna (CRA) made of novel electromagnetic bandgap (EBG) superstrate as partially reflecting surface (PRS) and reactive impedance surface (RIS) backed rectangular patch antenna. To the best of the authors' knowledge, the proposed EBG exhibits the highest stopband bandwidth (BW) with a bandgap existing between 7.37 and 12.4 GHz (50.9%). Frequency-selective property of the EBG is utilized under plane wave incidence to demonstrate it as PRS superstrate in CRA antenna. The cavity is excited with a rectangular microstrip antenna which is made of two dielectric substrates with an additional RIS layer sandwiched between them. The RIS provides wideband impedance matching of the primary feed antenna. A 7 × 7 array of the EBG superstrate is loaded over the patch antenna having an overall lateral dimension of only 45 × 45 mm2 or 1.62 λ0 × 1.62 λ0 where λ0 is the free space wavelength at the center frequency of 10.8 GHz. The proposed Fabry–Perot CRA (FP-CRA) achieves gain enhancement of 6.59 dB as compared with the reference antenna and has a 10 dB return loss BW of 23.79% from 10.07 to 12.79 GHz. A prototype of the FP-CRA is fabricated and experimentally tested with single and dual layers of EBG superstrate. Measured results show BWs of 21.5 and 24.8% for the two cases with peak realized gain of 12.05 and 14.3 dBi, respectively. Later a four-element antenna array with corporate feeding is designed as the primary feed of the CRA. The simulation result shows a flat gain of &gt;13 dBi with gain variation &lt;1.2 dB over the impedance BW of 13.2%.

Performance Improvement of Aperture Coupled MSA through Si Micromachining

In recent times rectangular patch antenna design has become the most innovative and popular subject due to its advantages, such as being lightweight, conformal, ease to fabricate, low cost and small size. In this paper design of aperture coupled microstrip patch antenna (MSA) on high index semiconductor material coupled with micromachining technique for performance enhancement is discussed. The performance in terms of return loss bandwidth, gain, cross-polarization and antenna efficiency is compared with standard aperture coupled antenna. Micromachining underneath of the patch helps in to reduce the effective dielectric constant, which is desirable for the radiation characteristics of the patch antenna. Improvement 36 percent and 18 percent in return loss bandwidth and gain respectively achieved using micromachined aperture coupled feed patch, which is due to the reduction in losses, suppression of surface waves and substrate modes. In this article along with design, fabrication aspects on Si substrate using MEMS process also discussed. Presented antenna design is proposed antenna can be useful in smart antenna arrays suitable in satellite, radar communication applications. Two topologies at X-band are fabricated and comparison between aperture coupled and micromachined aperture coupled are presented. Index Terms—Microstrip Patch Antenna, Aperture Coupled, Micromachining, High Resistivity Silicon

High Gain Beam Steering Antenna Arrays with Low Scan Loss for mmWave Applications

In millimeter-wave (mmWave) communications, the antenna gain is a crucial parameter to overcome path loss and atmospheric attenuation. This work presents the design of two cylindrical conformal antenna arrays, made of modified rectangular microstrip patch antenna as a radiating element, working at 28 GHz for mmWave applications providing high gain and beam steering capability. The microstrip patch antenna element uses Rogers RO4232 substrate with a thickness of 0.5 mm and surface area of 5.8 mm × 5.8 mm. The individual antenna element provides a gain of 6.9 dBi with return loss bandwidth of 5.12 GHz. The first antenna array, made by using five conformal antenna elements, achieves a uniform gain of approximately 12 dBi with minimal scan loss for extensive scan angles. In the second antenna array, a dielectric superstrate using Rogers TMM (10i) was used to modify the first antenna array. It enhanced the gain to approximately 16 dBi while still maintaining low scan loss for wide angles. The proposed array design method is very robust and can be applied to any conformal surface. The mathematical equations are also provided to derive the array design, and both array designs are verified by using full-wave simulations.

Design and Analysis of a 35 GHz Rectenna System for Wireless Power Transfer to an Unmanned Air Vehicle

In this article, the concept of a 22-kW microwave-powered unmanned aerial vehicle is presented. Its system architecture is analyzed and modeled for wirelessly transferring microwave power to the flying UAVs. The microwave system transmitting power at a 35 GHz frequency was found to be suitable for low-cost and compact architectures. The size of the transmitting and receiving systems are optimized to 108 m2 and 90 m2, respectively. A linearly polarized 4 × 2 rectangular microstrip patch antenna array has been designed and simulated to obtain a high gain, high directivity, and high efficiency in order to satisfy the power transfer requirements. The numerically simulated gain, directivity, and efficiency of the proposed patch antenna array are 13.4 dBi, 14 dBi, and 85%, respectively. Finally, a rectifying system (rectenna) is optimized using the Agilent advanced design system (ADS) software as a microwave power receiving system. The proposed rectenna at the core of the system has an efficiency profile of more than 80% for an RF input power range of 9 to 18 dBm. Moreover, the RF-to-DC conversion efficiency and DC output voltage of the proposed rectenna are 80% and 3.5 V, respectively, for a 10 dBm input power at 35 GHz with a load of 1500 Ω.

Detection of MDMA using Rectangular Microstrip Patch Antenna

Objective: This study is to design and analyze a rectangular microstrip patch antenna (MPA) for detecting 3,4-Methylenedioxy methamphetamine (MDMA) in the human body. The antenna's performance characteristics including resonant frequency, return loss, gain, VSWR, and radiation pattern are investigated to assess its suitability for drug detection applications. Methods: The rectangular microstrip patch antenna (MPA) is designed using electromagnetic simulation software. The antenna is optimized to resonate at a frequency sensitive to the presence of MDMA. The simulation results are analyzed to determine the resonant frequency, return loss, gain, VSWR, and radiation pattern of the antenna. The antenna's performance is evaluated under various conditions to assess its effectiveness for MDMA detection. Results: The proposed rectangular microstrip patch antenna (MPA) exhibits a resonant frequency of 1.3918 THz with a return loss of 41.136 dB and a VSWR of 1.0177034. The antenna achieves a gain of 7.993 dBi and demonstrates a radiation pattern suitable for MDMA detection. These results indicate that the designed antenna is promising for detecting MDMA in the human body due to its specific resonant characteristics and performance metrics. Conclusion: The designed rectangular microstrip patch antenna (MPA) shows potential for detecting 3,4-Methylenedioxy methamphetamine (MDMA) based on its resonant frequency, return loss, gain, VSWR, and radiation pattern. The antenna's resonant frequency aligns with the presence of MDMA, making it suitable for sensing applications aimed at drug detection in biological environments. Further experimental validation is recommended to verify its performance in real-world scenarios.

A Simple Model to Compute the Characteristic Parameters of a Slotted Rectangular Microstrip Patch Antenna

In this study, we developed an analytical model of slot-loaded rectangular microstrip patch antennas based on the simulation results by varying slot parameters. The dominant resonant frequency predicted by such a model is in strong agreement with the experimental results measured at several locations of slot-loaded rectangular microstrip patch antennas. The model enables a reliable and quick computation of the resonant frequency, which generally follows a harmonic behavior that nearly resembles the resonant frequency of a microstrip antenna without a slot, which can be related to a small change in the impedance caused by the slot position. Results showed a good agreement between simulations and measurements for all the slot positions. Mathematical analytic functions to describe the changes in specific characteristic parameters of the slot-loaded rectangular microstrip patch antennas are also included.

Comparison of FR4 and Roger substrates in multiband two-slot rectangular patch antenna for 5G applications

This study discusses the design, optimization, and simulation of a multiband microstrip patch antenna. The patch antenna is popular because of its compact form, which allows it to be smaller and lighter than other existing devices. The microstrip patch antenna is designed in a variety of designs, optimized, and simulated, with the two slot rectangular patch antenna being chosen due to its excellent performance. The proposed two-slot rectangular patch antenna's behaviour is further improved by using two different substrate materials. Because of their ease of manufacture, the FR4 and Roger substrates were used. The suggested antenna is capable of operating in three frequency bands ranging from 10 to 40 GHz. A partial ground plane approach is used to increase the antenna's return loss and bandwidth. CST (Computer Simulation Technology) Studio Suite was used to investigate the antenna parameter. The antenna operates at 10, 28, and 38 GHz, which are the selected frequencies for 5 G mobile communications by the International Telecommunication Union (ITU).

AMC Integrated Multilayer Wearable Antenna for Multiband WBAN Applications

In this paper, a compact, efficient and easy to fabricate wearable antenna integrated with Artificial Magnetic Conductor (AMC) is presented. Addition of slots and bevels/cuts in the rectangular monopole patch antenna yield a wide bandwidth along with band notches. The proposed antenna is backed with an AMC metasurface that changes the bidirectional radiation pattern to a unidirectional, thus, considerably reducing the Specific Absorption Ratio (SAR). The demonstrated antenna has a good coverage radiating away from the body and presents reduced radiation towards the body with a front-to-back ratio of 13 dB and maximum gain of 3.54 dB. The proposed design operates over a wide frequency band of 2.9 to 12 GHz (exceeding the designated 3.1−10.6 GHz Ultra-Wideband (UWB) band). The band notches were created using slots on the radiating patch in the sub-bands from 5.50 to 5.67 GHz and 7.16 to 7.74 GHz. The overall dimensions of the structure are 33 × 33 × 6.75 mm3. The antenna's radiation performance increased considerably with the addition of the AMC layer. The SAR values for the antenna are reduced by 85.3% when the AMC is used and are 0.083 W/kg which is well below the FCC SAR limits. The simple design, miniaturized profile, low SAR and wide operating bands with multiple band notches make the presented antenna an appealing choice for several UWB wearable body area network (WBAN) applications.

Performance Analysis of Rectangular Microstrip Wearable Textile Antenna with Series of Slots

In this paper the design of a wearable antenna for industrial, scientific, and medical (ISM band) applications at 2.4 - 2.45 GHz and 5.7 - 5.85 GHz is discussed. The rectangular microstrio patch antenna is considered and two series of slots are implemented with same length and different length. The conductive and ground planes are made from copper and cloth, respectively. Copper serves as a conductor in this case, while textile material serves as a barrier between the human body and the antenna. Micro strip feeding is supplied here to improve the antenna's reliability. The performance of the antenna will be evaluated using the simulation and practical as well, the reflection coefficient, VSWR, gain and radiation pattern of Microstrip textile antennas is obtained which used in a variety of ISM band applications.

A Comparative Study in Different Structures of Microstip Patch Antenna Design

Microstrip antenna consists of a metallic patch on a grounded substrate. It may be rectangular or circular patches. MSA become very popular for its ease of analysis and in fabrication, attractive radiation characteristics and low cross polarization radiation. In this paper, the proposed antennas are selected as UWB self-complementary Monopole antennas. I represent here the comparative study of Microstrip rectangular and hexagonal Patch antenna and their characteristics like Radiation pattern, VSWR vs. frequency, s-parameter vs. frequency, Impedance vs. frequency, current density etc.

Designing and Analysing of a Modified Rectangular Microstrip Patch Antenna for Microwave Applications

The microstrip patch antenna is commonly recognised for its diversity in term of achievable structures that make them appropriate to a wide variety of applications. The lightweight and compact size of the structure make these types of antennas suitable for use besides the microwave embedded circuits two more of their diverse benefits. In this paper, a modified design of the rectangular Microstrip Patch Antenna (MPA) beside edge feeding technique is simulated and optimised to cover a multi-band of the microwave frequency. The proposed antenna has been analysed based on the High-Frequency Structure Simulator (HFSS) using an FR-4 substrate. The introduced MPA design constitutes of a radiating patch from copper metal with a copper extension directly coupled to the lowest edge of the radiating patch via three stubs to covering three operating frequency bands: f1= 6.19 GHz (6.13-6.26 GHz), f2= 7.63 GHz (7.55-7.7 GHz), and f3=10 GHz (9.3-10.82 GHz). Consequently, the obtained results of the modified antenna design show a good gain with S11&lt;10 dB in the previous operating frequency bands, which are suitable for most wireless communication applications.

Pentagonal-shaped slot two port MIMO antenna for sub 6 GHz 5G wireless applications

In this paper, two-element multiple-input-multiple-output (MIMO) antenna system is presented for future sub-6 GHz 5G applications with improved impedance matching and isolation. In first design, a single rectangular patch antenna of 16.76 mm × 14 mm with pentagonal shaped slot and defected ground structure is proposed with a gain of 2.79 dB for WLAN (5.2 GHz) application. Second design consist of two elements MIMO patch antenna of dimension 16.76 mm × 47 mm × 1.6 mm on front side and defected ground structure on the back side of a FR4 substrate. The resonance frequency of antenna is 5.2 GHz with S11 = S22 = −26.47 db and good isolation between two ports and gain is 6.83db. Simulation has been performed on CST studio suite.

Design of a Novel Split-Bowtie Slotted Multi-Resonant Antenna

This article demonstrates a novel design of a split-bowtie slotted multi-resonant antenna. The design process was inspired from previous research of integrating a slot of a similar profile to the outer boundary of a rectangular patch antenna. The followed approach presents steps of proposed antenna evolution, which starts with a bowtie-shape slotted antenna and a coaxial feed to a final design with a split-bowtie-shaped slot, and a double transmission line feed. Polar dimensions of the outer boundary (radii and angle) and slot profiles together with the dimensions of the feed, whether coaxial or transmission line, were considered as parameters for optimization. Four antennas were accordingly studied, which led to the final split-bowtie-shaped antenna IV. These designs were performed utilizing a special simulation package called "CST Microwave Suite" that included the optimizer "Genetic Algorithm". The final design offers 4 simultaneous bands from a single split-bowtie-shaped slot; a big advantage of unnecessary integration of a set of complicated slots on front and ground planes. Further, the antenna finds applications in mobile GSM and LTE bands 900/1800 MHz and 2.1 GHz, together with the satellite communications band 1.25 GHz. It is therefore simple, non-reconfigurable, easy to fabricate, designed on a single copper layer, with a low cost FR4 substrate and a plane copper ground.