Design of X‐Band Broadband H‐Shaped Slit‐Coupled Microstrip Patch Antenna Array

A broadband high-gain leaf-like end-fire array antenna is proposed in this paper. The proposed antenna consists of a long microstrip line with two ports and 2 × 16 periodical radiating elements. The microstrip line is suspended in vacuum and fed by port1. One end of the radiating element is short-circuited to the ground through a rectangular short patch, and the other end is connected to the microstrip line through a horizontal leaf-like patch. The horizontal leaf-like patch is utilized to improve the impedance matching and enhance radiation of the short patch. The proposed antenna is a leaky-wave antenna which usually have the characteristics of high gain and low profile. Using vacuum as substrate improves the bandwidth and end-fire performance of antenna. The simulated −10 dB impedance bandwidth is 32% @5.3 GHz (4.4GHz- 6.1 GHz) and gain is 14.9 dBi at 5.3 GHz, 3-dB gain bandwidth is 32% @5.3 GHz (4.1 GHz- 5.8 GHz). Eventually, the simulation results verify that the proposed design has the characteristics of broadband and high gain.

To improve the compactness, broadband, high gain and wide coverage performance of the shortwave antenna (array), this paper introduces the array technology from the LPDA unit antenna, establishes the compact optimization model of the 2×3 elements LPDA fan-shaped array, and proposes an optimization method applied to the broadband decoupling and grating lobe suppression for LPDA fan-shaped phased array, taking the broadband low coupling and non-grating lobe as constraints; By using phased array technology, the wide scanning characteristics of LPDA fan-shaped array are analysed, and the influence of antenna parameters on the mutual coupling is studied when LPDA phased array widely scan. Finally, the feasibility of the truss based 2×3 elements LPDA fan-shaped phased array with a scale of 1:60 is verified through tests. The fan-shaped phased array has a frequency coverage of 13~28 MHz, an average gain of 17.5 dBi in the band, an average beam width of ≥ 30 °, and a scanning range of ≥ 90 °. The proposed array has the characteristics of broadband, low coupling, high gain, wide scanning and compactness. The proposed joint optimization method provides a very promising technical means for the optimization design of complex multi-dimensional phased arrays.

A methodology of designing an E-band ridge waveguide 48 × 48 slot array antenna with low sidelobe levels (SLLs), high gain and wide bandwidth characteristics is proposed in this paper. A 2 × 2 cavity-backed slot subarray acts as the unit cell of the array which consists of three layers. The top metal layer contains two radiating slots with different sizes to achieve wide bandwidth. The intermediate layer contains the back cavity and coupling slot and the third layer is the ridge waveguide with a metal step, so that the electromagnetic wave can be better transmitted through the coupling hole to the back cavity in the second layer. The array antenna is composed of 576 (24 × 24) unit cells with equal space and excited by a nonuniform corporate-feed-network. The SLLs are suppressed by the Taylor amplitude-tapering distribution, which is implemented by the unequal power dividers. It should be noted that we adopt a special feeding network topology and a large power distribution ratio to achieve the Taylor distribution because the array is composed of 576 unit cells, the number of which is not the n th power of 2. Simulation results of the array antenna show the -10 dB impedance bandwidth is from 70 to 77GHz, the peak gain is up to 41.6dBi and the first SLL is lower than -21 dB. In addition, the grating lobes around 40 degrees have also been suppressed to a certain extent. The antenna proposed in this paper is competitive for foreign object debris applications because of its wide bandwidth, narrow beamwidth, high peak gain and low SLLs.

This article presents a high-gain antenna array with the use of magnetoelectric (ME) dipole antenna elements operating at millimeter-wave frequencies. The proposed array achieves wide bandwidth, high gain, and low sidelobe level (SLL) in its planar structure. A highly efficient power divider consisting of pillbox transition and corporate feed network is introduced to produce equal phase but nonuniform power distributions to all array elements such that it can be for suppressing the SLL of the array. The radiating element is constituted by a cavity-backed slot-coupled ME dipole, which offers a wide impedance bandwidth and a stable radiation pattern. A prototype of the antenna array is fabricated and measured to verify the proposed design. The array achieves an impedance bandwidth of 20.8% (for the reflection coefficient ≤ -10 dB), covering the frequency range from 54.2 to 66.8 GHz. The average gain of the array is 28.5 dBi in its operating bandwidth, with a peak gain of 29.6 dBi at 65 GHz. The lowest E-plane SLL level over the entire bandwidth is -18 dB. This proposed antenna array has potential applications in long-distance millimeter-wave communications due to its merits of wideband, high gain, and low SLL features.

A K-band broadband circularly polarized antenna array is proposed in this paper. The antenna unit is a multiple-layer microstrip antenna, which is fed by H-type / U-type gaps coupling. It can realize the characteristics of broadband, circular polarization, small volume, light weight and high radiation efficiency. Based on this unit, an <tex>$8\times 8$</tex> antenna array, which has the characteristics of high gain, low side-lobe, low profile, beam-scanning, is finally designed and fabricated. Within the bandwidth of <tex>$\mathrm{f}0\pm 2\text{GHz}$</tex>, the VSWR of the array antenna is no more than 1.8. At the center frequency point f0, the gain of the antenna array is greater than 22dB, the 3dB beam width can reach 13 &#x00B0;, and the side-lobe level is less than &#x2212;14dB., which is very suitable for communication equipment of space-based measurement and control system.

In this paper, a microstrip patch array antenna with high gain and wideband for dual transmitting/receiving at Ku-band is presented. The patch array antenna has a horizontal polarization for Rx band and a vertical polarization for Tx band. A unit element of the patch array antenna consists of one radiating patch and two parasitic patches for improving impedance bandwidth and gain characteristics, and Tx/Rx feed circuits for bidirectional communication. For obtaining high gain, the unit patch elements are arranged the form of a 1/spl times/8 array structure. To verify the practicality of this antenna, we fabricated a 1/spl times/8 microstrip patch array antenna and measured the antenna pattern. As a result, we obtain that the gain of the dual Tx/Rx array antenna is 17.1/spl sim/18.1 dBi at 11.7-12.75 GHz and 14.0-14.5 GHz. The impedance bandwidth is about 10% at Rx band and 11% at Tx band. The cross-polarization level is below -25dB, and the sidelobe level is below -9.4dB.

This paper presents a low-cost compact planar microstrip-fed monopole antenna and its four-element array design for ultra-wideband (UWB) wireless communication and target detection applications, respectively, operating in the frequency span of 3 GHz to 11 GHz. A prototype was fabricated and then measured based on optimal parameters. The results of reflection coefficient (S11) and radiation patterns are shown and discussed. There is good consistency between the simulated S11 and the measured one. In addition, a 1 × 4 linear array design with the size of 100 mm × 34 mm has been proposed to achieve a higher gain. Simulation shows that the array gain is increased about 6 dBi in comparison to the single element through the whole UWB frequency range. The proposed array has an average of -15 dB side lobe level (SLL) in the mentioned range. And also, a -23 dB SLL has been achieved by applying Dolph-Chebyshev amplitude distribution at 6 GHz. Simulation results confirm that the antenna exhibits a constant bidirectional radiation pattern with a high and flat gain in case of the array design.

ABSTRACTA broadband and high gain circularly polarized stacked antenna with small size was designed. The antenna includes a double‐Y type slot radiator and two slot‐loaded patches with chamfering. Right hand circular polarization performance is achieved by adjusting the length of the two branch of Y type slot. In order to expand the antenna impedance bandwidth and axial ratio (AR) bandwidth, multilayer structure was used. Two patches with chamfering were chosen for radiating element. With the form of orthogonal, rectangular slot cut on the center of the two patches, small size of antenna can be achieved. The measurements show that, the proposed antenna's −10 dB impedance bandwidth is 32.7% (from 4.1 to 5.7 GHz), the 3 dB (AR) bandwidth is 20.7% (from 4.4 to 5.4 GHz) and the gain of the antenna is about 9 dB, which agree well with the simulations. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:292–298, 2017

The paper presents a microstrip patch array antenna for transmitting (Tx) and receiving (Rx) in the Ku band. The patch array antenna has horizontal polarisation for the Rx band and vertical polarisation for the Tx band. The element of the patch array antenna was designed as a three-stacked structure consisting of one radiation patch and two parasitic patches for high gain and wide bandwidth characteristics. The unit elements were arranged in a 1×8 array using a mixture of series and parallel feeds. To verify the practicality of this antenna, a three-stacked patch array antenna was fabricated and its performance was measured. The gain of the array antenna in the Rx and Tx bands exceeded 17 and 18 dBi, respectively. The impedance bandwidth was over 10% in both bands. The cross-polarisation level was below −25 dB, and the sidelobe level was below −9.4 dB.

A novel design of low profile circularly polarized antenna with performances of high gain and broad bandwidths is presented in this paper. Through the method of connecting the radiating patch to the ground plane by the metal wall, the peak gain of the antenna can be achieved as high as 11.8 dBi. Furthermore, In order to improve the axial ratio (AR) and impedance bandwidths, broadband 90° phase-shifter is introduced as feeding network. Annular-ring structure acts as radiating patch instead of circular patch can further improve the AR bandwidths. The measured results show that the antenna possess an impedance (VSWR ⩽ 2) bandwidths of 23.3% ranging from 1.87 GHz to 2.36 GHz, and right-handed circular polarized (RHCP) axial ratio (AR ⩽ 3dB) bandwidths of 24.3% ranging from 1.84 GHz to 2.35 GHz relative to the center frequency of 2.1 GHz, which agree well with simulated results.

In recent years there is a need for more compact antennas due to rapid decrease in size of personal communication devices. This paperdeals with the problem of size and performance of antenna. This paper presents design and simulation of a square micro strip patch antenna at 2.6 GHz for S- Band communications that provides a radiation pattern along a wide angle of beam and achieves a good gain. The square micro strip patch antenna was analyzed using Ansoft/Ansys HFSS. The proposed inset feed square patch antenna provide good Resonant Frequency, Return Loss, VSWR, Radiation Pattern and the antenna Gain. Index Terms: Micro strip antenna, Inset feed, Return Loss I. Introduction Micro strip patch antennas (also just called patch antennas) are among the most common antenna types in use today, particularly in the popular frequency range of 1 to 6 GHz. This type of antenna had its first intense development in the 1970s, as communication systems became common at frequencies where its size and performance were very useful. At the same time, its flat profile and reduced weight, compared to parabolic reflectors and other antenna options, made it attractive for airborne and spacecraft applications. More recently, those same properties, with additional size reduction using high dielectric constant materials, have made patch antennas common in handsets, GPS receivers and other mass-produced wireless products. This tutorial article is intended to provide basic information on patch antenna design and operation, directed to engineers who are mainly designers of RFmicrowave circuits. The paper hope that this information will assist them as they design circuitry connected to these antennas, or as they are called on to evaluate and specify a vendor's antenna product for their current project. Antennas are indispensable elements of any wireless communication systems. There are several type of antenna are available they are wire antenna, log periodic antenna, travelling wave antenna, micro strip antenna, aperture antenna, reflector antenna. The wire antenna comprises of several antenna they are short dipole antenna, dipole antenna, half wave dipole, broadband dipole, monopole antenna and loop antenna. In spite of this antenna, in this project micro strip antenna is designed with frequency of 2.6GHZ.Micro strip antenna comprises of 2 antennas theyare rectangular micro strip (patch) antenna and planar inverted-F antenna Micro strip or patch antennas arebecoming increasingly useful because they can be printed directly onto a circuit board. Micro strip antennas are becoming very widespread within the mobile phone market. Patch antennas are low cost, have a low profile and are easily fabricated. Micro strip antennas find many applications as they are low profile, light weight, conformable to surface and inexpensive to manufacture using printed-circuit technology. For a patch, the length L of the element is usually the L< λg/2 (where λg is the guide wavelength on the substrate). Thicker substrates with lower dielectric constant provide better efficiency and larger bandwidth but at the expense of larger element size. Thin substrates with higher dielectric constants lead to smaller element sizes, minimize coupling, but are less efficient and have relatively smaller bandwidth. Micro strip patch antennas have enjoyed proliferated use in many circularly polarized applications due to their low-profile and useful radiation characteristics. In the last decade, the development of modern wireless systems has prompted increased investigation on micro strip radiators, with particular attention paid to improving performance and miniaturization. Compared to a circular patch for a given frequency the square geometry is smaller in size. In modern communication system requires low profile, light weight, high gain, and simple structure antennas to give surety reliability, mobility, and high efficiency characteristics. Due to the existence of growth in development of low cost, less weight, highly reliable, minimal profile antennas for wireless devices, it poses a new challenge for the design of antenna in wireless communications. This paper presents design and simulation of a square micro strip patch array antenna at 2.6 GHz for wireless communications that provides a radiation pattern along a wide angle of beam and achieves a good gain. The rest of the paper has been divided into Fiveparts.Section 1 describes overview of antenna. Section 2 describes an overview of the Micro strip patch antenna. Section 3describesdesign consideration of antenna.Section 4 describes simulation results. Section 5 describesthe conclusion and future work respectively.

In the era of Internet of Things (IoT), the Internet has evolved from a simple Internet function of web information access to intelligent functions of identification, position, monitoring, and management of things. Devices in the IoT must transmit data between the devices and equipment connecting to cloud. As a fog computing architecture is established proximally at the local ends of the IoT, the data transmission volume and transmission delay can be effectively reduced. IoT wireless communication is one of the essential items for complete data transmission between the devices and on-line equipment. This paper proposes the low noise amplifier (LNA) design that can be applied to the RF front-end receiver of a 2.45-GHz wireless communication system for IoT applications. The LNA is required to have characteristics of low noise factor and high signal gain in order to amplify weak signals received by the antenna. In this study, the design of 2.45-GHz LNA adopts an architecture of power-constrained simultaneous noise and input matching on the basis of the 0.18-μm CMOS process technology in order to achieve simultaneous noise and input matching at low power conditions. Both the architectures of push-pull and forward substrate bias are also utilized. The LNA demonstrates the characteristics of low noise factor, high gain, and good 1-dB gain compression. The LNA shows good potential for IoT wireless communication system applications.

Digital terrestrial broadcasting services are in the Japanese UHF band of 470 to 770 MHz. The bandwidth of the UHF-TV channel is 6 MHz. The batwing radiator, which is at the heart of the super-turnstile antenna system for FM and VHF-TV broadcasting, has broadband characteristics. In this paper, we investigated a modified batwing antenna for UHF digital terrestrial broadcasting. The characteristics of the two- and four-element modified batwing antennas, with an infinite or a finite wire reflector, were calculated using NEC-WIN Pro. We evaluated the characteristics of these antennas in the Japanese UHF-TV broadcasting band. A broadband input impedance and high gain were obtained in the calculation and the measurement. A four-plane arrangement of parallel batwing antennas was also examined for directionality. The batwing element was arranged in parallel, and the feed interval was a half-wavelength. High gain and wideband characteristics were obtained with simple power-supply construction. This antenna has sufficient characteristics for use as the transmitting antenna for digital terrestrial broadcasting stations and repeater stations in the Japanese UHF band.

A low-profile dual-polarized shared-aperture phased array antenna is proposed for Ku-band satellite communications in this paper. The stacked octagonal patches loaded with Via-rings are proposed as dual-polarized shared-aperture radiation elements, with the characteristics of wide impedance bandwidth, high gain, and weak coupling. Furthermore, innovative minimized three-port ring couplers are utilized for the differential-fed antenna array, further suppressing the cross-polarization component. Substrate integrated coaxial line (SICL) and microstrip line (MS) feed networks are employed for the excitation of transmitting band (Tx) horizontal polarization and receiving band (Rx) vertical polarization, respectively. The non-uniform subarray architecture is optimized to minimize the sidelobe levels with the reduced number of transmitter and receiver (T/R) radio frequency phase-shifting modules. As proof-of-concept examples, 16 × 24 and 32 × 24 array antennas are demonstrated and fabricated. The measured impedance bandwidths of the proposed phased array antennas are around 21.1%, while the in-band isolations are above 36.7 dB. Gains up to 29 dBi and 32.4 dBi are performed by two prototypes separately. In addition, the T/R phase-shifting modules are utilized to validate the beam-scanning characteristic, which is of value for dynamic satellite communications.

Design and implementation of high gain dual-polarized antenna for sub-6GHz applications