Most of modern techniques for the surfacewave suppression are related to periodic structures, such as photonic bandgap pbg or electromagnetic bandgap ebg geometries, which require complicated processes and considerable area. Consider the side view of a patch antenna, shown in figure. Improvement of circularly polarized slotpatch antenna. The fundamentals of patch antenna design and performance. Dec 04, 2012 radiation efficiency, h, and unloaded radiation q, q o, as a functionof substrate thickness. Microstrip patch antenna consists of a radiating patch on one side of a dielectric substrate fr4 that has a ground plane cu on the other side as shown in fig. This work is mainly focused on increasing the gain as well as reducing the size of the unidirectional patch. The simulated 3d radiation patterns of the stackedpatch antennas with and without the shs are shown in fig. Microstrip antenna radiation pattern sixtysec youtube.
The most popular technique for the improvement of the radiation performance of patch antennas on a largesize substrate is to construct an artificial periodic structure, such as photonic bandgap pbg or electromagnetic bandgap ebg 5, 6, surrounding the patch antenna to prevent the surface waves from propagating in the substrate. A patch antenna is a type of radio antenna with a low profile, which can be mounted on a flat surface. Other configurations are complex to analyze and require. Isolation improvement of a microstrip patch array antenna. We will use the source antenna to illuminate the antenna under test with a plane wave from a specific direction. The radiation patterns and s11 performance are used for the analysis of the different configurations. Improvement of microstrip patch antenna radiation patterns ieee. A low profile, unidirectional, dual layer, and narrow bandwidth microstrip patch antenna is designed to resonate at 2. By way of improvement, this article proposes a new type of singlelayer logperiodic microstrip antenna. Radiationpattern improvement of patch antennas using a. Another common radiation pattern cut a cut is a 2d slice of a 3d radiation pattern is when is fixed and varies from 0 to 180 degrees.
Improvement of microstrip patch antenna radiation patterns abstract. Improvement of efficiency parameter of a microstrip patch. The most common type of microstrip antenna is the patch antenna. In the present endeavor a rectangular patch antenna is designed on thick substrate and. Microstrip patch antenna finds several applications in wireless communication. Analysis of the proposed antenna is done using the ie3d simulation software. For example, satellite communication requires circularly polarised radiation patterns, which can be realised using either square or circular patch microstrip antenna.
The proposed antenna is a circular microstrip structure excited by four feeds and suspended with artificial magnetic conductors amcs. The detailed variation of radiation pattern across its frequency band has been studied and presented in this paper. Afterward, radiation patterns of the crmpa in the e and h plane for both with and without rsdgs are shown in figure 5 and figure 6 respectively. Oneof the types of antenna is the microstrip patch antenna mpa. The radiation performance of patch antennas on a largesize substrate can be significantly degraded by the diffraction of surface waves at the edge of the substrate. It consists of a flat rectangular sheet or patch of metal, mounted over a. The multifeed circular microstrip antennas can generate a high circularly polarized performance by using a different feed arrangement. Rectangular patch antenna performances improvement employing.
This diagram shows the basic structure of the proposed logperiodic microstrip antenna. The approach can be applied to reduce the crosspolarization level of any conventional patch in working condition, but without any perturbation in the patch and the ground plane. The basics of patch antennas, updated orban microwave. A patch antenna is a narrowband, widebeam antenna fabricated by etching the antenna element pattern in. Improvement of a circular microstrip antenna excited by four. For example, satellite communication requires circularly polarised radiation patterns, which can be realised using either square or circular patch. Patch antenna surrounded by an ideal compact shs structure. Due to reciprocity, the radiation pattern from the. The bandwidth of this microstrip patch antenna is more than twice that of cpw fed microstrip rectangular slot antenna. The microstrip patch antenna is probably the best characterized of the planar microwave antennas and the most frequently used, yet its radiation pattern is often far. Pdf radiation pattern improvement of a microstrip patch antenna. Microstrip patch antennas typically have radiation patterns containing unwanted sidelobes or local minima caused by surface waves, especially when fabricated on high dielectricconstant substrates. Chapter 4 design of phi shaped microstrip patch antenna 35 in ie3d 4. Metamaterial enhances microstrip antenna gain microwaves.
When the antenna is excited, the waves generated within the dielectric undergo reflections and the energyis radiated from the edges of the metal patch,which is very low. The polarization and antenna gain for the fields radiated toward the test antenna of the source antenna should be known. Pdf improvement of microstrip antenna performance on thick and. Wideband unidirectional bowtie antenna with pattern improvement. Lowcost dielectric substrate for designing low profile. Amc structures with a square, circular, or octagonal patch on a unit cell are designed and applied to circular microstrip. The radiation patterns of the hexagonal patch antenna with slot in the ground plane are simulated at 3.
The main focus of this paper is to improve band width so that patch antenna is used for wide band applications and. Pdf radiation pattern improvement of a microstrip patch. Improvement of a circular microstrip antenna excited by. 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.
Efficiency improvement and crosspolarization reduction of. Initially, the farzone radiated fields of the mpa working in the tm 10 mode are. The microstrip antenna s radiation arises from the fringing fields, which are due to the advantageous voltage distribution. However, large sidelobes and small values of the realized gain are the weaknesses of the antenna. The microstrip antennahas been said to be the most innovative area in the antenna engineering with. Radiation patterns of the microstrip leaky wave antenna with d 31. Multiple patch antennas on the same substrate see image called microstrip antennas, can be used to make high gain array antennas, and phased arrays in which the beam can be electronically steered. A microstrip antenna array between two fss was proposed for application in wlan. This paper presents the isolation improvement techniques of a microstrip patch array antenna for the indoor wideband code division multiple access wcdma repeater applications. If the antenna had a 100% radiation efficiency, all directivity would be converted to gain. The designed microstrip patch antenna with four slits and a pair of truncated corners are simulated using cadfeko for finding the electric far field radiation, gain, directivity, radiation pattern e. A variant of the patch antenna commonly used in mobile phones is the shorted patch antenna, or planar invertedf antenna pifa. Microstrip antennas have long been used as reliable components with small profiles, large directional beams, and high gain. The fringing fields around the antenna can help explain why the microstrip antenna radiates.
Microstrip patch antennas or simply patch antenna are increasingly useful because the antenna is printed directly onto a circuit board. 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 conducting patch can take any shape but rectangular and circular configurations are the most commonly used configuration. It uses microstrip line capacitive coupling to feed a coplanar microstrip patch array. The microstrip patch antenna is a popular printed resonant antenna for narrowband microwave wireless links that require semihemispherical coverage. We will discuss later in this work more parameters of the antenna in connection with microstrip patch antenna like radiation pattern, efficiency, quality factor, directivity, gain, and more. The geometry of the circular microstrip patch antenna with three amc structures is shown in figure 6. It is observed from these figures that the antennas with rs. In addition, as the substrate thickness increases, the radiation q of the antenna decreases. Radiation pattern improvement of a microstrip patch antenna. A standard double ridged horn antenna is used as a reference antenna. Design and analysis of microstrip patch antenna arrays. 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. The microstrip antennas radiation arises from the fringing fields, which are due to the advantageous voltage distribution.
A variation of this technique, compatible with monolithic fabrication, is applied to. The same technique will be used for the ebg cirlcularly polarized circular slot patch antenna network and carry two benefits such as improvement of bandwidth, beamforming, creating zero radiation beams and filtering characteristics of the resonator spatial filtering, increased directivity, misalignment due to the resonant structure itself. Feb 16, 20 many types of antenna have been designed to suit with most devices. A good improvement in bandwidth for the antenna with the dummy. Properties of a basic microstrip patch a microstrip or patch antenna is a low profile antenna that has a number of advantages over. The industry standard, 3d full wave electromagnetic. The patch of the antenna must be a very thin conductive region, t antenna is designed to fabricate on ridge ground plane which has been compared with conventional structure and around 6% 7% improvement in bandwidth is revealed. A microstrip patch that uses a thicker substrate is more efficient.
This is a simple layout of the microstrip antenna showing the distance to a singlelayer metamaterial unit cell. The singlelayer design provides excellent structural strength and can be fabricated by means of standard singlelayer printedcircuitboard pcb technology. The performances of the mpa are implemented by resonating its radiative tm 10 and tm 12 modes at the lower and upper bands, respectively. Radiation pattern improvement of a microstrip patch antenna using electromagnetic bandgap substrate and superstrate article pdf available in wseas transactions on communications 61. Generally, hemispherical coverage is provided by a patch antenna at an angle of 30. The length of microstrip patch antenna is given by the following equations. A surface wave influence in radiation pattern is often considered unwanted. The following image shows a microstrip or patch antenna. Nov 25, 2016 in microstrip antenna, it is the fringing fields that are responsible for the radiation. Microstrip antenna an overview sciencedirect topics.
Therefore, three amc patch shapes with the substrate dielectric constant of 4. Study on the improvement of bandwidth of a rectangular microstrip patch antenna. Rectangular patch antenna performances improvement. In case of microstrip antenna, it is proportional to its quality factor q and given by as. A great circle cut is when 0 and is allowed to vary from 0 to 360 degrees. The microstrip antennahas been said to be the most innovative area in the antenna engineering with its lowmaterial cost and easy to fabricate which the process can be made inside universities orresearch institute. Bandwidth improvement for compact microstrip patch. A wideband microstrip antenna with symmetric radiation patterns a wideband microstrip antenna with symmetric radiation patterns kasabegoudar, veeresh g vinoy, k. The fabricated antenna was then placed inside an antenna chamber. Dualband singlelayer microstrip patch antenna with. One approach is to construct the singlefeed switchable feed network structure with an msnri coupledline coupler in order to reduce the mutual coupling level between antennas.
Here, the bandwidth of the antenna is defined as the 10 db. 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. Keywords rectangular microstrip patch antenna, antenna feed, antenna radiation pattern. Bw the percentage bandwidth of the rectangular patch micro strip antenna in terms of patch dimensions and substrates parameters is given as follows. The proposed microstrip patch antenna is compact, miniature,coste. Design of slotted ground hexagonal microstrip patch. Microstrip patch antenna 2 is widely used in communication systems as it has major advantages of unidirectional radiation patterns, low pro. Jun 01, 20 the radiation patterns of the hexagonal patch antenna with slot in the ground plane are simulated at 3. The use of two triangular structures for microstrip patch antennas to improve. Vinoy microwave laboratory, ece department, indian institute of science, bangalore, india 560 012.
Their low profile design, often square or rectangular, allows them to be mounted to flat surfaces. A dualband singlelayer microstrip patch antenna mpa with simultaneous improvement in impedance bandwidth and radiation beamwidth is proposed in this communication. Flexible and miniaturized design of microstrip patch antenna. Antennas using patches as constitutive elements in an array are also possible. Now that we have our measurement equipment and an antenna range, we can perform some antenna measurements. Standard techniques for improving the impedance bandwidth of a microstrip antenna. A microstrip patch antenna mpa consists of a conducting patch of any planar or nonplanar geometry on one side of a dielectric substrate with a ground plane on other side.
It is observed that there is a deep drop in the zdirection for the antenna without shs due to the diffraction of surface waves at. Flexible and miniaturized design of microstrip patch. A waveguide probe was used to measure the nearfield of the microstrip patch antenna and postprocessing was. Dualband singlelayer microstrip patch antenna with enhanced. In 20, the bandwidth of an aperture coupled microstrip patch antenna has been improved by using an appropriate impedancematching network using. Jun 18, 2012 the radiation patterns from a microstrip antenna are described in this sixtysec clip. In microstrip antenna, it is the fringing fields that are responsible for the radiation. Wideband unidirectional bowtie antenna with pattern. Study on the improvement of bandwidth of a rectangular. Performance optimization of microstrip antenna array using. Single microstrip layer holds uwb logperiodic antenna. The compact mm antenna exhibits a directive radiation patterns for all. It is a popular printed resonant antenna for narrowband microwave wireless links that require semihemispherical coverage.
Pdf microstrip patch antennas have some limitations such as restricted bandwidth of operation, low gain and a potential decrease in radiation. Directive stacked patch antenna for uwb applications hindawi. The radiation pattern can be represented in either cartesian or polar coordinates, as shown in figure 1. Design of slotted ground hexagonal microstrip patch antenna. Bandwidth improvement for compact microstrip patch antenna. Microstrip 2x1 element patch antenna array a modified 2x1 element array microstrip patch antenna is shown in figure 4. Improvement of microstrip patch antenna radiation patterns. So by rotating the antenna, we can obtain cuts of the radiation pattern for instance the eplane cut or the hplane cut. The design of 2x1 element microstrip antenna in order to enhance performance of the antenna like increasing gain, directivity scanning the beam of an antenna.
Thus, impedance bandwidth increases with increasing substrate thickness. The radiation pattern of microstrip or patch antenna is. The crmpa radiation patterns are simulated at a frequency of 2. The geometrical structure and configuration with detailed design parameters of the proposed patch antenna are shown in figure 1. Design and analysis of uwb microstrip patch antenna. Microstrip patch antennas typically have radiation patterns containing unwanted sidelobes or local minima caused by surface waves, especially when. Radiationpattern improvement of patch antennas on a large. Design and improvement of microstrip patch antenna. The paper shows that removal of the substrate beneath the patch can greatly improve the pattern. The patch antenna is therefore a voltage radiator, as opposed to the wire antennas, which radiate because the currents add up in phase and are therefore. The same technique will be used for the ebg cirlcularly polarized circular slotpatch antenna network and carry two benefits such as improvement of bandwidth, beamforming, creating zero radiation beams and filtering characteristics of the resonator spatial filtering, increased directivity, misalignment due to the resonant structure itself.
Radiation efficiency, h, and unloaded radiation q, q o, as a functionof substrate thickness. A miniaturized design of microstrip patch antenna has been proposed for significant improvement in crosspolarization purity. Radiation pattern improvement of a microstrip patch. Improvement in radiation parameters of rectangular microstrip. Jul 29, 2016 figure 3 shows the antennas simulated and measured radiation patterns, in the e and h planes at 10. The electric far field of the microstrip patch antenna is shown in figure. Design of 4 elements rectangular microstrip patch antenna. Geometry of microstrip patch antenna the width of the microstrip patch antenna was computed with the following equation. Many types of antenna have been designed to suit with most devices. Impedance bandwidth and gain improvement for microstrip. The radiation patterns from a microstrip antenna are described in this sixtysec clip.
Due to its planar configuration and ease of integration with microstrip technology, the microstrip patch antenna has been heavily studied and is often used as elements for an array. China 2 department of physics and electronic science, chuxiong normal university, chuxiong, 675000. A waveguide probe was used to measure the nearfield of the microstrip patch antenna and postprocessing was performed to obtain the farfield radiation patterns. Progress on the development of lightweight dual frequency. A wideband microstrip antenna with symmetric radiation. In addition, as the substrate thickness increases, the radiation q of the. The figure below represents the radiation pattern of the microstrip antenna. Figure 3 shows the antennas simulated and measured radiation patterns, in the e and h planes at 10. Improving the efficiency of microstrip patch antennas springerlink. Typical half wave patches have efficiencies well above 90%. Additional benefits of patch antennas is that they are easily fabricated making them cost effective. Gain enhancement of a microstrip patch antenna using a.
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