Pdf high directivity of microstrip patch antenna using. An antenna that radiates equally in all directions would have effectively zero directionality. A classical patch, such as a square shaped patch, presents a single lobed broadside pattern in its fundamental mode tm10 or tm01 with a low directivity. There are several reasons why microstrip antennas are so popular.
Enhancement of directivity of rectangular microstrip antenna using. A patch antenna is a type of radio antenna with a low profile, which can be mounted on a flat surface. In this present work, a microstrip patch antenna mpa using frequency selective surface fss is proposed. It is designed by using genetic algorithms with the advantage of not requir. A low profile, unidirectional, dual layer, and narrow bandwidth microstrip patch antenna is designed to resonate at 2. Radiation patterns, permittivity, directivity, and gain october 12, 2016 by mark hughes antennas allow information to be transferred to distant locations. It has low radiation power and narrow frequency bandwidth. With the development of wireless communication technology, 5g will develop into a new generation of wireless mobile communication systems.
The most common type of microstrip antenna is the patch antenna. We obtain the same directivity for linearly and circularly polarized patches because a circularly polarized patch is a linear combination of two linearly polarized patterns. Therefore, the design of high directivity microstrip patch antennas is a challenging task. The transmission line model, combined with the measured and computed thermal plots, suggest a model for the.
Design and simulation of microstrip patch array antenna with high directivity for 10 ghz applications conference paper pdf available november 2014 with 8,178 reads how we measure reads. Gain of an antenna in a given direction is defined as the ratio of the intensity, in a given direction, to the radiation intensity that would be obtaine. A very highquality factor is offered by a patch antenna. It is also less accurate, but gives a good physical insight. Design and simulation of microstrip patch array antenna. A single highdirectivity microstrip patch antenna mpa having a rectangular profile, which can substitute a linear array is proposed. Due to its advantages such as low weight, low profile planar. High directivity microstrip antennas comprising a driven patch and at least one parasitic element placed on the same plane, operate at a frequency larger than the fundamental mode of the driven patch in order to obtain a resonant frequency with a high directivity broadside radiation pattern. Antenna directivity and effective area we have seen that standard antennas emit more radiation in some directions than in others. An antenna that radiates equally in all directions would have effectively zero directionality, and the directivity of this type of antenna would be 1 or 0 db. Highdirectivity microstrip antennas comprising a driven patch and at least one parasitic element placed on the same plane, operate at a frequency larger than the fundamental mode of the driven patch in. Typical radiation pattern of a simple square patch.
Two dielectric superstrate layers, each a quarter wavelength in thickness and separated by an air gap, are introduced above the microstrip patch, separated by another air gap. Us20050285795a1 broadside highdirectivity microstrip. Alternate feed methods a common variation in patch antenna design is the location and routing of the feed, to obtain a desired feedpoint impedance, to. The presence of arrays of microstrip elements provides greater directivity, higher gain, increased transmission range with less interference. Radiation pattern and directivity of a linear rectangular microstrip patch antenna on globalspec. Additional benefits of patch antennas is that they are easily fabricated making them cost effective. It consists of a flat rectangular sheet or patch of metal, mounted over a larger sheet of metal called a. A large q results in a narrow bandwidth and low efficiency. The patch may be in a variety of shapes, but rectangular and circular are the most common. Several authors have proposed the use of superstrates to improve the performance of microstrip patch antennas 21, 22 that are used to excite the fabryperot resonators 12. Analysis and design of circular microstrip patch antenna at 5.
This work is mainly focused on increasing the gain as well as reducing the size of the unidirectional patch. In this article, we present the results of a comparative study of three different types of superstrates used to enhance the directivity of a microstrip patch antenna. Full writeup for 3rd edition is given directivity of microstrip patches including finite ground planes. For good antenna performance, a thick dielectric substrate having a low dielectric. But patch antennas can also be formed with a collection of multiple patches on a dielectric substrate. Indeed, it is topologically impossible for an antenna to emit transverse waves. Radiation pattern and directivity of a linear rectangular. Typical half wave patches have efficiencies well above 90%. Enhancement of gain and directivity for microstrip antenna using. The distance between the patch and the ground plane the. Two dielectric superstrate layers, each a quarter wavelength in thickness and separated.
Micro strip patch antennas patches are in variety of shapes, such as rectangular, square. What is the difference between slot antenna and patch. Threeelement vectors of cartesian coordinates in meters. The three superstrates are frequency selective surface fss with dipole elements. Enhancement of microstrip antenna directivity using double. This may be replaced with a physical shorting plane to create a quarterwavelength microstrip antenna. Kumar, nishant, ashutosh kumar pandey, aditya prakash, shiv mani kumar, rupali bihari, and manas ranjan jena. Pdf high directivity of microstrip patch antenna using metamaterial. Feb 10, 2017 directivity is a measure of the concentration of radiation in the direction of the maximum. The directivity of patch antennas is approximately 57 db. The fundamentals of patch antenna design and performance. What is the difference between directivity and antenna. The proposed antenna is suitable for specific applications, such as security and. Dec 04, 2012 the patch usually fed along the centerline to symmetry and thus minimize excitation of undesirable modes.
Pdf design and simulation of microstrip patch array. Deschamps in 1953, but didnt become practical until the 1970s when it was developed further by researchers such as robert e. Us20050285795a1 broadside highdirectivity microstrip patch. A novel highdirectivity microstrip patch antenna based on. Gain and directivity enhancment of microstrip patch antenna using. Download scientific diagram directivity of patch antenna at 2. Their low profile design, often square or rectangular, allows them to be mounted to flat surfaces. Conventional single element microstrip patch antennas have a low directivity 67dbi 1.
Microstrip patch antennas are used for communication purposes especially in military and civil applications. Click here to go to our page on circular patch antennas new for september 2018. Enhancement of directivity of rectangular microstrip. A comparative study of directivity enhancement of microstrip. A microstrip or patch antenna is a low profile antenna that has a number of advantages over other antennas it is lightweight, inexpensive, and easy to integrate with accompanying electronics. Demonstration of an xband multilayer yagilike microstrip. Aug 07, 2014 a microstrip or patch antenna is a lowprofile antenna that has a number of advantages over other antennas. To achieve the dualfrequency antenna, the conventional patch antenna is excited along the diagonal.
The antenna only has a single radiation edge equivalent slot which lowers the directivity gain of the antenna. Microstrip patch antenna directivity, antenna design. Micro strip antennas are easy to fabricate and comfortable on curved surface. The fields are linearly polarized, and in the horizontal direction when viewing the microstrip antenna as in figure 1a well see why in the next section. In this case, each vector starts at the origin and lies along the specified points on the x, y, and zaxes. The directivity of a microstrip patch can be found from the cavity models of patches and integrated over the hemisphere to compute directivity. The transmission line model, combined with the measured and computed thermal plots, suggest a model for the computation of radiation patterns of a rectangular microstrip patch antenna in the tm 01 mode.
Other researchers working independently, suggested that directivity. Improving microstrip patch antenna directivity using ebg. Microstrip patch antennae radiate primarily because of the fringing fields between the patch edge and the ground plane. To achieve the dualfrequency antenna, the conventional.
The proposed antenna is suitable for specific applications, such as security and military systems, which require a narrow bandwidth and a small antenna size. The radiation pattern of microstrip or patch antenna is broad. Pdf a highdirectivity microstrip patch antenna design. Pdf a highdirectivity microstrip patch antenna design by. The halfwave rectangular microstrip antenna has a virtual shorting plane along its center. One familiar application of this type of patch antenna is the rectangular antenna usually in a plastic housing used widely in 2. Design, simulation and analysis a microstrip antenna using. Microstrip patch antennas or simply patch antenna are increasingly useful because the antenna is printed directly onto a circuit board. Next well consider more aspects involved in patch microstrip antennas. The directivity is fairly insensitive to the substrate thickness.
Us8026853b2 broadside highdirectivity microstrip patch. In this paper a simple microstrip patch antenna is designed in cst microwave studio at a resonant frequency of 2. High directivity of microstrip patch antenna using metamaterial muhammad waqas1, shahid bashir2, muhammad junaid. Also called patch antennas one of the most useful antennas at microwave frequencies f 1 ghz. In this paper, the directivity of microstrip patch antennas with doublelayer superstrate is investigated. Microstrip patch antenna consists of a dielectric substrate, with a ground plane on the other side. The radiation pattern of a microstrip or patch antenna is shown above. In the second part of this antenna basics series, you will learn more about the physics of how antennas work. Gain enhancement of a microstrip patch antenna using a.
However, conventional microstrip patch antenna suffers from low radiation gain and narrow bandwidth. Normalized radiation pattern for microstrip patch antenna. It is a measure of how directional an antennas radiation pattern is. The fields are linearly polarized, and in the horizontal direction when viewing the microstrip antenna as.
It usually consists of a metal patch on top of a grounded. One familiar application of this type of patch antenna is the rectangular. It is a measure of how directional an antenna s radiation pattern is. It is promising to reduce the lateral radiation and obtain an enhanced directivity when the sng mtms are applied in the microstrip patch antenna. In this paper a simple microstrip patch antenna is designed in cst microwave studio at a. Pdf in this paper, a different double negative dng metamaterial is demonstrated to upgrade the performance of microstrip patch antenna mpa. So far, the directivity has been defined with respect to an isotropic source and. Microstrip patch antenna geo metry in addition, they ar e used to scan the beam of an ante nna system, increase the directivity, and perform various other functions which would be difficult with. Design and analysis of microstrip patch antenna arrays. A patch antenna is a narrowband, widebeam antenna fabricated by etching the antenna element pattern in metal trace bonded to an insulating dielectric substrate, such as a printed circuit board, with a continuous metal layer bonded to the opposite side.
Microstrip antennas introduction slide 4 a microstrip patch antenna is a metallic strip or patch mounted on a dielectric layer substrate over a ground plane. Transmissionline model it is the easiest approach to model and analyze the microstrip patch antenna. Enhancement of directivity of rectangular microstrip antenna. It usually consists of a metal patch on top of a grounded dielectric substrate. Arrays of microstrip elements in the antenna configuration provide greater directivity. Genetic algorithm optimization of a highdirectivity. Rectangular patch analysis microstrip patch antennas slide 18 the rectangular patch is the most widely used configuration for microstrip patch antennas. Therefore, the design of highdirectivity microstrip patch antennas is a challenging task. Additional benefits of patch antennas is that they are easily. The performance and advantages of microstrip patch antennas such as low weight, low profile, and low cost made them the perfect choice for. A microstrip or patch antenna is a lowprofile antenna that has a number of advantages.
Yagilike microstrip patch antenna with high directivity and large bandwidth nasatm20052554 april 2005 national aeronautics and space administration glenn research center prepared for the international symposium on antennas and propagation and usncursi national radio science meeting sponsored by the institute of electrical and. Either single or multiple feed lines are used to provide excitation to the antenna. Microstrip antenna an overview sciencedirect topics. If the antenna had a 100% radiation efficiency, all directivity would be converted to gain. In this letter, a novel high directivity microstrip patch antenna mpa based on planar zeroindex metamaterials is presented. An averaging effect over the metamaterial structure yields an effective permittivity that approaches zero at 8. We obtain the same directivity for linearly and circularly. What is the difference between directivity and antenna gain. Fundamental specifications of patch antennas radiation pattern a patch antenna radiates power in certain directions and we say that the antenna has directivity usually expressed in dbi. Antennas using patches as constitutive elements in an array are also possible. Microstrip antennas have become fashionable in some wireless communications systems, such as in the use of arrays with parabolic reflectors or even in the use of a patch antenna in the back of a cellular phone, as shown in figure 5. The patchmicrostrip object is a microstrip patch antenna.
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