Dual-band Microstrip Research Articles

Design of a Symmetric CPW-Fed Patch Antenna for WLAN/WIMAX Applications Using ANN

This article presents a coplanar waveguide fed dual-band microstrip patch antenna for Wireless Local Area Network and Worldwide Interoperability for Microwave Access applications. The proposed antenna is designed using the artificial neural networks (ANN) method based on the multilayer perceptron structure; it is composed of a coplanar ground plane with a circular patch conductor printed on the FR4 dielectric substrate. The fabricated antenna configuration has a global dimension of 24 $$\times $$ 33.5 $$\times $$ 1.56 mm $$^{3}$$ . The proposed antenna presents numerous advantages like small size, low profile, and simple structure. The operation properties such as reflection coefficient, current distribution, radiation pattern, gain, and radiation efficiency are presented and discussed respectively using both ANSYS HFSS and CST MWS electromagnetic simulators. A dual band presenting three resonant frequencies is achieved by predicting the dimensions of the added slots in the radiating patch using the ANN technique. The measured − 10 dB impedance bandwidths are 390 MHz (2.17–2.56 GHz) centered at 2.46 GHz and 3670 MHz (2.82–6.49 GHz), which presents two resonant frequencies 3.73 GHz and 6.20 GHz, as the measured and the simulated results have a good agreement. Moreover, the designed antenna presents good radiation pattern over the operating bands.

Integration of RF rectenna with thin film solar cell to power wearable electronics

AbstractThis paper reports an integration of dual band microstrip antenna with thin film amorphous silicon solar cell which creates a wearable system to harvest microwave energy. The multiple layers in the encapsulation of the thin film solar cell are used as a substrate for microstrip antenna. The rectifier and matching circuit are designed on cotton jeans material and the whole system is mechanically supported by the foam of 5 mm thick. The performance of the antenna is studied for the mechanical bending condition. The device has maintained good power conversion efficiency. The efficiency of the voltage doubler is tested by varying radio frequency power levels from −30 to10 dBm. The voltage doubler conversion efficiency at 1.85 and 2.45 GHz are 58 and 43%, respectively, for a load of 7.5 kΩ for an input power level of −5 dBm.

A Rectangular Microstrip Patch Antenna for Dual Band Wireless Applications

Background: In this paper, the design of a dual-band microstrip patch antenna with operating frequencies of 2.16 GHz and 2.79 GHz is proposed. Methods: The proposed antenna design is based upon the defected ground structure and rectangular patch with corner cuts. The presented antenna structure is simulated and optimized using CST microwave studio software. Results: The antenna resonates at 2.16 GHz and 2.79 GHz. The bandwidth of the proposed antenna is 2.08 GHz-2.25 GHz at center frequency 2.16 GHz and is 2.7 GHz-2.87 GHz at center frequency 2.79 GHz. The optimized antenna model is fabricated and measured. The measured and simulated results are presented and discussed. The proposed antenna provides a maximum gain of 4.463 dB and the maximum directivity of 5.846 dBi. The maximum radiation efficiency and total efficiency of the antenna are 79.85% and 69.01%, respectively. Conclusion: The proposed antenna is suitable for dual-band wireless applications.

Design and Development of Single & Dual Resonant Frequency Antennas for Moisture Content Measurement

The microstrip antenna is designed for the measurement of soil moisture content for agriculture applications. In this paper, the single and dual-band microstrip antennas are designed, simulated and fabricated. The simulated results are compared and analysed with measured results for both designed for different types of feeds. It is found that the simulated and measured results are similar and better. Therefore, the fabricated antennas can be used for the soil moisture content measurement for agriculture applications. The dual resonant frequency antennas results are better than the single band antenna, it covers wide band thus, and it can be applied for wide applications.

A CPW - Fed Microstrip Monopole Antenna Employing Inverted Quad L Shaped Stubs with Symmetrical Slotted Rectangular Ring Ground Planes for GPS/PCS/UMTS and UWB Applications

In this research article, a simple and compact dual-band microstrip monopole antenna is discussed. A CPW feed is given to patch consisting of rectangular coplanar ground sheets on either side, truncated their centers with smaller rectangular sheets giving the shape of rectangular rings. The proposed antenna is designed using FR4 epoxy substrate having dielectric constant 4.4 and thickness 1.6mm. The main element in the antenna is four inverted L shaped stubs which govern the impedance bandwidth of the antenna. Simulations are carried out using HFSS software. The S11 plot for the proposed antenna showed dual-band characteristics with a lower band ranging from 1.09GHz to 2.33 GHz (1.24 GHz bandwidth) and the upper band covering 3.01 GHz to 10.738 GHz (7.728 GHz bandwidth). The proposed antenna bandwidth ranges of the proposed antenna will be covering the GPS, PCS and UMTS applications for lower band and UWB applications for upper band. The antenna exhibited a peak of 3.01 dB and 4.54 dB at 1.89 GHz and 9.45 GHz. Simulations are carried and all the important findings are plotted.

CPW - Fed Microstrip Monopole Antenna Employing Inverted Quad L Shaped Stubs with Symmetrical Slotted Rectangular Ring Ground Planes for GPS/PCS/UMTS and UWB Applications

In this research article, a simple and compact dual-band microstrip monopole antenna is discussed. A CPW feed is given to patch consisting of rectangular coplanar ground sheets on either side, truncated their centers with smaller rectangular sheets giving the shape of rectangular rings. The proposed antenna is designed using FR4 epoxy substrate having dielectric constant 4.4 and thickness 1.6mm. The main element in the antenna is four inverted L shaped stubs which govern the impedance bandwidth of the antenna. Simulations are carried out using HFSS software. The S11 plot for the proposed antenna showed dual-band characteristics with a lower band ranging from 1.09GHz to 2.33 GHz (1.24 GHz bandwidth) and the upper band covering 3.01 GHz to 10.738 GHz (7.728 GHz bandwidth). The proposed antenna bandwidth ranges of the proposed antenna will be covering the GPS, PCS and UMTS applications for lower band and UWB applications for upper band. The antenna exhibited a peak of 3.01 dB and 4.54 dB at 1.89 GHz and 9.45 GHz. Simulations are carried and all the important findings are plotted.

Application of FSS for Microstrip Antenna for Gain Enhancement

In this present paper, a dual-band microstrip patch antenna (MPA) using frequency selective surface (FSS) is proposed. The dual-band MPA is designed using the rectangular shaped patch with an elliptical slot at the center of the patch and full ground plane. The FSS in this paper act as a reflection plane which is loaded onto the dual-band MPA in order to improve the gain of the antenna at higher band. The FSS is obtained by the periodic array of 3 × 5-unit cell in the x-y direction, which based on the amalgamation of a square and circular loop elements. After merging the FSS, the gain and return loss at 5 GHz increased to 0.915 dB and -25.08 dB respectively. The dual-band MPA is simulated using the FR-4 substrate with a thickness of 1.6 mm and a relative permittivity of 4.4. The overall size of the MPA and FSS is relatively compact and easy to fabricate. The proposed antenna can be used in WiMAX and WLAN applications.

Design Implantable Antennas with Human Body Effect

Implantable antenna devices have made great progress for healthcare services. Amongst the overall components of the implantable device, the antenna is the most important component that exists; it used to transmit the biological data wirelessly from inside the human body tissues to an external receiver. However, the human body tissues’ surrounding the antenna decrease the performance of the radiation antenna device, change its characteristics and absorbs most of its radiation. It also limits the size of the implantable device and its battery. Therefore, the design of the implanted antenna inside the human body requires many challenges while meeting many contradictory design parameters at the same time. Therefore, in this research, we mainly focused our spotlight on investigating and designing new antenna structures with robust performance against the human body tissue effect. In this research work, we presented two designs of a dual-band microstrip patch implantable antenna to operate ((401-406 MHz) Medical Device Radio-Communications (MedRadio), 433MHZ 2.45 GHz Industrial, Scientific and Medical (ISM) bands, respectively. This is to satisfy the requirements of data transfer, power saving and wireless power transfer. The first design in this paper is a new shape of microstrip patch implantable antennas with meandered serpentine slot, with a single feed point. This shape of design allows us to increase the length of the current path in order to decrease the antenna size and covers MICS and ISM bands with new dimensions of (31 x 25 x 1.63) mm, the measured frequencies range we obtained it’s from 378MHz to 450 MHz (17.3%) at the lower band and from 2.46 to 2.68 GHz (8.56%) at the upper band for 11 less than -10 dB. The second simulated design is a compact dual-band Planar Inverted-F Antenna (PIFA) with Open-End Slots on ground with dimensions of (19.8x19.4x1.27) mm the measured frequencies from 325MHz to 407MHzrange at the lower band and from 2.412GHz to 2.482GHz for PIFA antenna, the designs of both antennae constructed and measured using CST and HFSS simulation and measurement setup. We also explained and demonstrated the performance of these antenna designs and the effect of human body tissue on antenna parameters, based on the reflection coefficient in normal and bent conditions.

Design and Analysis of Frequency Reconfigurable Dual-Band Microstrip Patch Antenna for Wireless Communication

Design and Analysis of Frequency Reconfigurable Dual-Band Microstrip Patch Antenna for Wireless Communication

A dual‐band dual‐mode microstrip Yagi antenna with quasi‐end‐fire radiation

A dual-band dual-mode microstrip Yagi antenna with quasi-end-fire radiation patterns is proposed in this paper. It consists of five radiating patches driven by a single slot-loaded patch placed in the middle. Meanwhile, two slot-loaded parasitic patches are symmetrically located on two sides of the driven patch, respectively. In the lower band, the five patches involved resonate at TM01 mode. While in the upper band, all the patches resonate at TM02 mode. In order to ensure quasi-end-fire radiations in the both bands, four slots are symmetrically etched around the strongest surface currents of each patch resonating at TM02 mode. As a result, the resonant frequency of TM02 mode is decreased dramatically, while the resonant frequency of TM01 mode almost remains unchanged. With these arrangements, the separations between any two of the adjacent patches at their centers satisfy the requirements in design of the microstrip Yagi antenna in both bands, so as to realize the dual-band dual-mode microstrip Yagi antenna on a single-layer substrate. Finally, an antenna prototype is fabricated and tested. The measured results reveal that the dual operating bands of 2.76~2.88 and 4.88~5.03 GHz for |S11| < −10 dB are satisfactorily achieved. Most importantly, the proposed antenna can indeed realize the quasi-end-fire radiation patterns in dual operating bands.

Optimal design of a large dual-polarization microstrip reflectarray with China-coverage patterns for satellite communications

A large dual-polarization microstrip reflectarray with China-coverage patterns in two operating bands is designed. To sufficiently compensate for the spatial phase delay differences in two operating bands separately, a three-layer rectangular patch element is addressed, which is suitable for the large dual-polarization reflectarray. Due to the complexly shaped areas and high gain requirements, there are more than 25 000 elements in the reflectarray, making it difficult to design, due to more than 150 000 optimization variables. First, the discrete fast Fourier transform (DFFT) and the inverse DFFT are used to establish a one-to-one relationship between the aperture distribution and the far field, which lays a foundation for optimizing the shaped-beam reflectarray. The intersection approach, based on the alternating projection, is used to obtain the desired reflection phases of all the elements at some sample frequencies, and a new method for producing a suitable initial solution is proposed to avoid undesired local minima. To validate the design method, a dual-polarization shaped-beam reflectarray with 7569 elements is fabricated and measured. The measurement results are in reasonable agreement with the simulation ones. Then, for the large broadband reflectarray with the minimum differential spatial phase delays in the operating band, an approach for determining the optimal position of the feed is discussed. To simultaneously find optimal dimensions of each element in two orthogonal directions, we establish a new optimization model, which is solved by the regular polyhedron method. Finally, a dual-band dual-polarization microstrip reflectarray with 25 305 elements is designed to cover the continent of China. Simulation results show that patterns of the reflectarray meet the China-coverage requirements in two operating bands, and that the proposed optimization method for designing large reflectarrays with complexly shaped patterns is reliable and efficient.

Dual-Wideband High-Gain Fabry-Perot Cavity Antenna

In this paper, we proposed a novel Fabry-Perot cavity antenna with high-gain radiation over two wide bands based on a partially reflective metasurface. To satisfy the resonance condition of the dual-wideband Fabry-Perot cavity, we constructed the unit cell of the partial reflection metasurface by loading magnetic coupling enhancement layers and etching the bottom patches. The partial reflection metasurface composed of the above unit cells can generate reflection phases of positive gradient with almost the same slope over two wide bands, where the partial reflection amplitude is close to 1. Subsequently, a normal dual-band microstrip antenna has also been designed for excitation. Finally, the Fabry-Perot cavity antenna consists of the proposed partial reflection metasurface and the dual-band antenna has been simulated, fabricated, and measured in a microwave anechoic chamber. Both simulation and experimental results demonstrate that the designed Fabry-Perot cavity antenna achieves 3-dB gain bandwidths of 20.7% and 10.1% with peak gains of 12.07dBi and 13.5dBi over two wide bands of 5.7-6.9GHz and 11.7-12.95GHz, respectively.

Design and Analysis of A Microwave Dual Band Microstrip Patch Antenna (MPA) for Wireless Communication Applications

This paper presents the design and simulation of a microstrip patch antenna (MPA) which is modeled by placing several rectangular copper layer with conductive characteristics on a substrate material with dielectric constant 3.0 and 22x18x1 mm3 geometry. This microstrip path was designed with copper material which had a very thin thickness for patch and ground. In this study, a change in resonance frequency and return loss characteristics were observed for several substrate thickness values. The radiation characteristics of the single and dual band microstrip patch antennas (MPAs) are analysed in the frequency range of 5 &amp;amp;ndash; 25 GHz. The microstrip patch antenna (MPA) radiate at a frequency of 15.32 GHz with -45 dB return loss. For the designed single and dual band MPA design, some electromagnetic properties such as return loss, surface current and radiation patterns were simulated. The characteristic of goods and chattels of the proposed antenna are analyzed by using the software CST Microwave Studio.

Circularly Polarized Array with Enhanced Isolation Using Magnetic Metamaterials

This article proposes a 2 × 2 circularly polarized array with enhanced isolation that could be used in the adaptive anti-jamming system for China’s Beidou Navigation Satellite System (BDS), and a compact dual-band microstrip antenna for GPS and GLONASS is designed at the center part of the array for multiple modes operation. The substrate integrated split ring resonators with negative effective permeability are used as the magnetic metamaterials. Four groups of the magnetic metamaterials are placed between the BDS antenna elements, which could constrain the EM filed in the area of the active element, and then significantly reduce the mutual coupling among the elements. The results tell that the isolation among the BDS elements are improved by more than 10 dB, and the performance of radiation patterns and the axial ratio of each BDS elements are also apparently improved compared to the array without magnetic metamaterials.

Dual-Band Single-Layer Microstrip Patch Antenna With Enhanced Bandwidth and Beamwidth Based on Reshaped Multiresonant Modes

A dual-band single-layer microstrip patch antenna (MPA) with simultaneous improvement in impedance bandwidth and radiation beamwidth is proposed in this communication. The performances of the MPA are implemented by resonating its radiative TM10 and TM12 modes at the lower and upper bands, respectively. Initially, the far-zone radiated fields of the MPA working in the TM10 mode are theoretically investigated. It demonstrates that its E-plane half-power beamwidth (HPBW) in the lower band is significantly widened by removing the array factor between dual equivalent slots. After that, the MPA working in TM12 mode is deeply studied and analyzed. The results depict that its wide E-plane HPBW and low H-plane sidelobe level (SLL) in the upper band could be obtained by reshaping radiation patterns of its improved TM12 mode via the shorting pins. Additionally, a linear slot is cut on the core radiator so as to achieve a good impedance matching. With these arrangements, the E-plane HPBW, H-plane SLL, and impedance bandwidth of this designed MPA can be simultaneously enhanced in the dual bands. Finally, the proposed antenna is fabricated and measured. The experimental results show that the antenna has gained an improved bandwidth ( $\vert S_{11}\vert –10 dB) ranging from 3.45 to 3.77 GHz and 5.75 to 6.04 GHz with two attenuation poles. Most importantly, the HPBW of its E-plane radiation pattern is successfully widened to around 135° over these dual operating bands. Moreover, the high H-plane SLL of the antenna is decreased to about −10 dB in the upper band.

Dual-Band Microstrip Corporate Feed Network Using an Embedded Metamaterial-Based EBG

This paper demonstrates the design and experimental validation of a dual-band microstrip (MS) corporate feed network using an embedded metamaterial-based electromagnetic bandgap (MTM-EBG) structure. The MTM-EBG is designed to appear as a $35.4~\Omega $ MS transmission line (TL) with a 90° electrical length at both 2.4 and 5.0 GHz. This structure is then used in place of a conventional single-band quarter-wavelength transformer in a $50~\Omega $ MS T-junction power divider, rendering it dual band with 10 dB return-loss fractional bandwidths of 82.3% and 12.0% at center frequencies of 2.4 and 5.0 GHz, respectively. The result of this modification shows a very good performance at both operating frequencies, as well as substantial rejection over a prescribed bandwidth of intermediate frequencies. The dual-band transformer formed by the embedded MTM-EBG is 30.5% miniaturized at 2.4 GHz relative to a conventional MS quarter-wavelength transformer, which indicates its potential for use in size-restricted scenarios and embedded filtering applications. A dual-band four-way corporate feed network is then formed by cascading the MTM-EBG-loaded T-junction power dividers, which is suitable for antenna array applications. This structure has an improved performance at 2.4 and 5.0 GHz compared to unloaded networks designed for these frequencies having the same overall size. The experimental 10 dB fractional bandwidth for the MTM-EBG-loaded corporate feed network was found to be 52.0% and 10.8% around 2.4 and 5.0 GHz, respectively.

Microstrip patch antenna feed for offset reflector antenna for dual band application

In this article, details of a dual band microstrip patch antenna (MPA) array feed for an offset reflector antenna is presented. The main objective of the proposed structure is to achieve low cross-polarization at Φ = 90° plane in the reflector pattern. Low cross-polar levels in the reflector pattern are achieved by illuminating the reflector with fields of the proposed dual band feed structure. A centered circular array as the dual band feed structure is proposed in which the central radiating element is a dual mode circular MPA operating at 6 GHz and the surrounding circular ring of eight circular MPA elements operating at 4 GHz in the dominant mode. The dual mode central antenna uses the concept of conjugate field matching for cross-polarization reduction. TM21 mode is excited at an appropriate ratio with the TM11 mode to achieve the proper field matching at 6 GHz. The radius of the surrounding circular array is varied to obtain cross-polarization better than −30 dB at both the resonant frequencies. The offset reflector gain is found to be better than 37 dB with a 2.5 m parabolic reflector and F/D = 0.8 at both the operating frequencies.

Dual-Band Differential Shifted-Feed Microstrip Grid Array Antenna With Two Parasitic Patches

A dual-band differential shifted-feed microstrip grid array antenna (DSF-MGAA) with two parasitic patches is presented in this communication. By moving the feed location, a conventional MGAA (C-MGAA) can be turned into an SF-MGAA for dual-band operation. The high-frequency band of SF-MGAA corresponds to the operation mode of the C-MGAA, and its low-frequency band is similar to that of the patch or meshed patch antenna. A new differential feeding scheme and two parasitic patches are adopted to improve the impedance bandwidth of SF-MGAA. The proposed DSF-MGAA can cover a dual band of 3.7 and 28.5 GHz. The measured −10 dB impedance bandwidths of 3.4% and 4.5%, which correspond to the peak gains of 8.98 and 19.2 dBi, are obtained in the low- and high-frequency bands, respectively. The DSF-MGAA can be a potential candidate for the future dual-band wireless communication.

A Compact Semi-Circular and Arc-Shaped Slot Antenna for Heterogeneous RF Front-Ends

In this paper, a new miniaturized compact dual-band microstrip slot antenna is presented. To achieve the dual-band characteristics, two adjunct partial arc-shaped small slots are joined to two main circular slots embedded in the ground of the antenna structure. With a reduced size of 30 × 28.5 × 0.8 mm3, the proposed antenna presents a dual-band characteristic. The design is optimized using a High Frequency Structure Simulator (HFSS) followed by experimental verifications. An impedance bandwidth, for S11≤10 dB, that covers the 1.8 GHz and 2.4 GHz bands is accomplished, which makes the proposed antenna basically suitable for hand-held devices and medical applications. More applications such as digital communication system (DCS) 1.71–1.88 GHz, personal communication services (PCS) 1.85–1.99 GHz, Universal and mobile telecommunications system UMTS 1.92–2.17 GHz, Bluetooth 2.4–2.5 GHz, and Wi-Fi 2.4–2.454 GHz, Industrial Scientific and Medical radio frequency (RF) band ISM-2.4 GHz, Wireless Local Area Network (WLAN-2.4)are possible by simply changing one of the geometrical antenna dimensions. The antenna is characterized by stable radiation patterns as well.

A diamond-shaped patch microstrip antenna with L-shaped stub for WLAN applications

This article proposes a Dual-band microstrip antenna with Diamond-shaped patch and L-shaped stub for two frequency bands of Wireless Local Area Network (WLAN) application. The combination of 50 Ω microstrip feed line and L-shaped stub, the upper frequency band of WLAN is obtained. This frequency band can be controlled by the length of ground plane. The proposed antenna benefits from omnidirectional radiation patterns for both frequency bands. The intended antenna is simulated by Ansoft HFSS v.15 and CST Microwave Studio and the results are compared. Also, the proposed antenna is implemented on an FR4 substrate with a thickness of 1.6 mm. According to measured results, S11 of less than -10 dB for frequency ranges of 2.3–2.7 GHz and 5–5.7 GHz with impedance bandwidths of 16% and 13%, respectively are achieved.