Gain enhancement of a microstrip patch antenna using a reflecting layer a low profile, unidirectional, dual layer, and narrow bandwidth microstrip patch antenna is designed to resonate at. In a receiving antenna, the gain describes how well the antenna converts radio waves arriving from a. Typical half wave patches have efficiencies well above 90%. Microstrip antennas are relatively inexpensive to manufacture and design because of the simple 2dimensional physical geometry. If you wanted to make a microstrip antenna to receive fm radio at 100 mhz it would be on the order of 1 meter long which is a very. The simulated results provided the improvement in gain i. How can i improve the gain of a patch antenna and what is. Microstrip antenna has popular attractive features such as low profile, low cost, small size and easily integrated with rf devices. The directivity of a microstrip patch can be found from the cavity models of patches and integrated over the hemisphere to compute directivity. The e and hfield halfpower 3db beamwidth was contracted by 47. However, these parameters are complimentary matrices, in that if one is improved, other is degraded. Directivity is a measure of the concentration of radiation in the direction of the maximum. Again, increased directivity implies a more focused or directional antenna. It is a measure of how directional an antennas radiation pattern is.
This work leads to conclusion that directivity, bandwidth and gain of microstrip antenna can be increased by covered dielectric and multidielectric structure with parasitic patch. Hence, if the antenna is 100% efficient, then the directivity would be equal to the antenna gain and the antenna would be an isotropic radiator. A method to improve the gain and directivity of the patch antenna using permeability negative metamaterial mtm cells is proposed. Enhancement of gain and directivity for microstrip antenna. In this paper, a study of new design of pentagonal microstrip patch antenna for wireless communications applications. Gain enhancement of a microstrip patch antenna using a.
Gain and directivity enhancement of rectangular microstrip patch antenna using. If the antenna had a 100% radiation efficiency, all directivity would be converted to gain. A low profile, unidirectional, dual layer, and narrow bandwidth microstrip patch antenna is designed to resonate at 2. The fundamentals of patch antenna design and performance. 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. Directivity calculate in cst patch antenna design using. High directivity of microstrip patch antenna using. The directivity of patch antennas is approximately 57 db. High gain patch antenna using a frequency selective. The gain and directivity of the designed antenna is 7. Gain and directivity enhancement of microstrip antenna loaded with. A patch antenna radiates power in certain directions and we say that the antenna has directivity usually expressed in dbi.
Enhancement of directivity of rectangular microstrip. Improving the performance of patch antena using microwave. In practice, gain is always less than the directivity d. The design and simulation of patch antennas is widely used in mobile cellular phones today, and our emphasis in this work is on optimization of a 2. Enhancementof gain, bandwidth and directivity of a patch. Metamaterial enhances microstrip antenna gain microwaves. The figure below shows the directivity of a patch antenna. 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 results shows that the directivity is enhanced by 56 % as compare to conventional rectangular patch antenna. A single patch antenna provides a maximum directive gain of around 69 dbi. A microstrip or patch antenna operates in a way that when current though a feed line reaches the strip of the antenna, then electromagnetic waves are generated. Sometimes the antenna gain is given with reference to a dipole antenna and is labelled as dbd. Gain and directivity enhancement of rectangular microstrip patch antenna using hfss.
Gain and directivity enhancement of rectangular microstrip. Microstrip antennas have high q q 100 is common, which means that they have small bandwidths. 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. Thanks a lot how do i calculate the gain of a microstrip patch and array antenna. This means that if sidelobe level from the radiation pattern were down db, and directivity of the antenna was 4 db, sidelobe gain would be 9 db.
Normalized radiation pattern for microstrip patch antenna. Gain and directivity enhancement of rectangular microstrip patch. Their low profile design, often square or rectangular, allows them to be mounted to flat surfaces. In this paper a simple microstrip patch antenna is designed in ads at a resonant frequency of 3. Air as a substrate can give you maximum gain for a specific design since it has no. 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. New compact pentagonal microstrip patch antenna for. The directivity is calculated for antenna 1 to be 1. Two conventional microstrip patch antennas whose resonance frequency bands. In this present work, a microstrip patch antenna mpa using frequency selective surface fss is proposed. The presence of arrays of microstrip elements provides greater directivity, higher gain, increased transmission range with less interference. This work is mainly focused on increasing the gain as well as reducing the size of the unidirectional patch antenna.
Composing of duallayer symmetry single ring resonator pair dssrrp embedded on both sides of the dielectric layer, the mtm cell is easy to integrate with a patch antenna and can be used as an insulator to reflect surface waves based on the. The use of metamaterials in single or multiple layers has been shown to contribute a great deal to the design of a highgain microstrip antenna at 10. However, conventional microstrip patch antenna suffers from low radiation gain and narrow bandwidth. Additional benefits of patch antennas is that they are easily fabricated making them cost effective. Without changing the original microstrip patch antenna size, the use of metamaterials made it possible to nearly double antenna directivity. For a microstrip antenna to work, you want to think the opposite thoughts that you might want to think if you were designing a microstrip mmic. Microstrip patch antennas or simply patch antenna are increasingly useful because the antenna is printed directly onto a circuit board. The directivity is calculated for antenna 2 to be 2. Conclusions a novel, compact, dual polarized microstrip patch antenna is presented. Tm stands for a magnetic field distribution between patch and ground that is transverse to the zaxis of the antenna shown in figure 1. 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. The antenna gain with reference to an isotropic source is given in dbi decibel above isotropic source. Ali a thesis submitted in partial fulfillment of the requirements for the degree of master of science in electrical engineering approved by. Results and discussion several parameters like gain, directivity, radiation efficiency and return losses of antenna with transmission line are simulated and compared between conventional mpa and dng based mpa is discussed below.
Request pdf gain and directivity enhancement of microstrip patch array antenna with metallic ring for wlanwifi applications a novel gain and directivity. Gain enhancement of patch antenna integrated with metamaterial. Improving microstrip patch antenna directivity using ebg. This transverse with respect to the zaxis is usually dropped because the magnetic fields in patch antennas are always transverse to their zaxis. A slotted rectangular microstrip patch antenna for bandwidth enhancement which is excited by two. At xband a microstrip antenna is on the order of 1 centimeter long easy to realize on softboard technology. The directivity or gain of an antenna is defined as the ratio of the maximum value of the power radiated per unit solid angle to the average power radiated per unit solid angle. The basics of patch antennas, updated orban microwave. Therefore the directivity of the micro strip antenna is expanded by. Gain enhancement of microstrip patch antenna using dielectric dng superstrate by abdulbaset m. Gain enhancement of a microstrip patch antenna using a reflecting. The 3dimensional plot of the gain of an antenna is known as the radiation pattern.
Microstrip patch antenna finds several applications in wireless communication. One familiar application of this type of patch antenna is the rectangular antenna usually in a plastic housing used widely in 2. Design of a rectangular microstrip patch antenna using. 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 electromagnetics, an antennas power gain or simply gain is a key performance number which combines the antennas directivity and electrical efficiency. Gain is related to directivity with antenna efficiency factor as. As a transmitting antenna, the gain describes how well the antenna converts input power into radio waves headed in a specified direction. Antenna gain is related to the antenna type, fr4 is lossy material therefore you can not expect large gain from fr4. Hi all, i am new herei have some questions and i hope i can get some answers here. 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. Octagon metamaterial, gain, directivity, microstrip antenna, double. By suppressing backwardwave radiation, antenna gain increased by 3. Microstrip patch antenna directivity, antenna design. Conventional single element microstrip patch antennas have a low directivity 67dbi 1. Enhancement of gain and directivity for microstrip antenna using. The directivity of a patch can be estimated quite easily.
Add the reflector and it directs most of the light in the sa. They are usually employed at uhf and higher frequencies because the size of the antenna is directly tied to the wavelength at the resonant frequency. A high gain rectangular microstrip patch antenna using di. Gain and bandwidth are essential design parameters of a wireless communication system. Optimization of directivity and gain performances on circular patch. The results shows that the directivity is enhanced by 56% as compare to conventional rectangular patch antenna. In the proposed design a size reduction of 50% with a high isolation38dband low crosspolarization level is demonstrated, albeit, with a reduction in the broadside directivity by 3. The proposed antenna has regular pentagonal patch provide dual bands 2. Therefore, the design of highdirectivity microstrip patch antennas is a challenging task.
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. This video clearly explains how to extract different results from a simulated antenna return loss, gain, vswr, directivity, radiation pattern. Directivity calculate in cst for patch antenna antenna,microstrip,patch antenna,coaxial cable,radio,microwave engineering,probe feed,cst,coaxial feed using c. 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. Thus the microstrip patch radiation intensity depends on what direction you are facing it from it has gain and directivity. The new fss structure is then applied as a superstrate to a conventional microstrip. A single patch antenna on fr4 can produce gain of 35dbi. The proposed dual layer microstrip patch antenna has an impedance. Gain and directivity enhancment of microstrip patch antenna using. High antenna gain is generally desirable for communications systems, whether terrestrial or based on satellites. What is the difference between directivity and antenna gain.
Abstract a novel design of a new frequency selective surface nfss is presented, characterized and employed for the gain enhancement of a microstrip antenna operating at 5. In this work, the simulation tool of ie3d is used to study the performance and gain of the rectangular microstrip patch antenna. Horii and tsutsumi 1999 presented microstrip patch antenna having. The torch bulb on its own without the reflector is like an isotropic antenna radiating in all directions. Since all antennas will radiate more in some direction that in others, therefore the gain is the amount of power that can be achieved in one direction at the expense of the power lost in the others. The fringing fields at the edge of a microstrip antenna which radiate are centered about each edge of the. In a transmitting antenna, the gain describes how well the antenna converts input power into radio waves headed in a specified direction. I like to simplify things in my head and imagine a torch light. Gain enhancement of microstrip patch antenna using. This paper comprises one novel technique in order to increase the bandwidth, gain and directivity of the. High gain fss aperture coupled microstrip patch antenna. Gain and directivity enhancement of microstrip patch array antenna. Microstrip antenna an overview sciencedirect topics.
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