The patchmicrostrip object is a microstrip patch antenna. The strips are symmetrical along the center line of the width of the patch, and the gap. It is very easy to analyze by using both the transmission line and cavity models, which are most accurate for thin substrates 4. The use of a single shorting plane to create a quarter wave patch antenna was first described by sanford and klein in 1978 31 later, post and stephenson 32 described a transmission line model to predict the driving point impedance. Input impedance of rectangular microstrip patch antenna with isoanisotropic substratesuperstrate abstract. I suggest you to view this patch antenna concept post, if you are a novice to patch antenna design. Analysis and design of rectangular microstrip patch antenna. I have gone through many threads in the forum about finding the input impedance of patch antenna, however all the replies cant catch my mind. For achieving the better efficiency of the antenna, the better impedance matching is required in between coaxial probe and patch. We use a simple rectangular, half wave long, probefed patch operating in its fundamental mode as an example. Design of a rectangular microstrip patch antenna using. The figure below shows the geometry of the rectangular microstrip antenna, not including the ground plane and dielectric which would be underneath. The dimensions of antenna can be found in the hfss simulation file.
Note that a quarterwave length transformer was used to match the patch to a 50 ohm feed line. The conventional patch antenna equations were taken from 10 and 11 asmention previously in chapter 2. Experimental study of stacked rectangular microstrip antenna. In this case, each vector starts at the origin and lies along the specified points on the x, y, and zaxes. What is the difference between slot antenna and patch. 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. Experimental study of stacked rectangular microstrip. The basics of patch antennas, updated orban microwave. How do we calculate the input impedance of a patch antenna. Coax fed patch antenna with waveport at different location. Design a rectangular microstrip patch antenna for wlan application sanjay singh1, kishor chandra arya2, rachna arya3 1,2m.
It is worth to mention that, the rectangular patch width w has a minor effect on the resonant frequency and radiation pattern of the rectangular patch antenna 2. Input impedance of rectangular microstrip patch antenna. Microstrip antenna an overview sciencedirect topics. From the last meeting that we discussed,our group are able to run the simulation of cst in designing the rectangular microstrip patch antenna. The bandwidth impedance of the antenna is 150mhz and 1. This rectangular microstrip antenna design is known as a quarter wave microstrip patch or half patch antenna. The microstrip antenna can also be matched to a transmission line of characteristic impedance z0 by using a quarterwavelength transmission line of characteristic impedance z1 as shown in figure 2. Oct 10, 2007 in short, this article has presented some quick design graphs to determine the dimensons of a rectangular patch antenna for a frequency or frequencies of interest, using the plotted curves to also find the input impedance at a resonant frequency and the circuit q. Microstrip antenna, stacked patch antenna, dualband antenna, network analyzer, bandwidth. Patch antenna is actually a patch antenna placed over a antenna base. The power transfer between a source and antenna is done through a feed line. We use the cavity model to explain the operation of the patch antenna. The modified wolff model mwm, which is an improved version of the cavity model, is presented to compute the resonance frequency and input impedance of a rectangular microstrip patch antenna under the isotropicanisotropic substrate. Solved find the input impedance of patch antenna in hfss.
The input impedance and length of the patch antenna decides the optimal input impedance point. Actually, slot antenna is a radiating element formed by a slot in a metallic surface. Coax fed patch antenna with waveport at different location this example demonstrates the use of a coaxial probefed rectangular microstrip patch antenna. It is used in applications from mhz to thz frequencies when size, weight, cost, reliability, and aerodynamic performance are constraints.
Microstrip patch antenna is used in mobile handset due to simple look, lower cost, small size and light in weight. The rectangular patch antenna is a lowprofile antenna composed of a patch of metal mounted onto a substrate that is backed by a metallic ground plane. These are very low size antennas having low radiation. Patch antenna with a quarterwavelength matching section. The benefit of this feeding method is that the connector can be put at any location withinthe patch to match the impedance. The four most popular feed techniques used in patch antenna are the microstrip line, coaxial probe both contacting schemes, aperture coupling and proximity coupling both noncontacting. It consists of rectangular substrate and the metal trace layer as shown in fig. Ogunlade michael adegoke, ismael saad eltoum department of electronics engineering. The fundamentals of patch antenna design and performance. The connectors to the antenna are located at the edges of the patch to achieve a simulated antenna impedance of 300. Absract in this paper, a rectangular microstrip patch antenna is designed. Following equations or formula are used for this microstrip patch antenna calculator. Analysis and design of rectangular microstrip patch antenna at 2. This antenna does not take any much extra size and can be etched on the same mobile pcb itself.
Design of rectangular microstrip patch antenna part 1 matlab. Microstrip line feed, coaxial probe feed, and aperturecoupled feed techniques. Their low profile design, often square or rectangular, allows them to be mounted to flat surfaces. How do we calculate the input impedance of a patch antenna from its dimension.
Schematic of a rectangular patch antenna electromagnetically coupled to two inverted microstrip line feeds for dual linear polarization and frequency. Richards, theory and experiment on microstrip antennas, ieee trans. In this post, i tried to use python utils and libs for designing a patch antenna. A broadband rectangular microstrip patch antenna for. After that, we will choose the l matching network as the best method for improving the impedance matching and the gain of a microstrip antenna. Click here to go to our page on circular patch antennas new for september 2018. The major problems of the single element microstrip antennas are low gain and narrow bandwidth which limit their wide applications. As we know the current distribution on the ground plane of the conventional patch antenna mainly concentrates just under the patch, as shown in figure 3, which is the vector current distribution of the resonant frequency 5. The patches can be rectangular, square, circular, triangular, annular or elliptical in shape. The input impedance of rectangular microstrip patch antenna is investigated by many researchers 7, 12, 14, 16, 20, 23, 25, 28, 3839. Image of voltage v, current i, impedance z curve along the length of patch. A metal patch mounted at a ground level with a dielectric material inbetween constitutes a micro strip or patch antenna. Comparative study on different feeding techniques of. Design and implementation of patch antenna 7 mmic designs, and when the particular patch shape and mode are selected, they are very versatile in terms of resonant frequency, polarization, pattern, and impedance.
Microstrip patch antenna calculator patch antenna formula. This work suggests that the proposed antennas configurations provide a. Cst microwave studio, and the thz signal is directly vertically coupled to the drain terminals without the use of waveguides. By following these basic guidelines, this compact, lowcost, lightweight patch antenna can be matched to applications operating at both 1. Inset shows the geometry of a circular patch antenna with segments removed for a similar experiment. This article introduces the basic concepts of patch antennas. In this model, a rectangular microstrip antenna patch, of figure 3, is viewed as a resonant section of a microstrip transmission line, since it has a physical structure derived from microstrip transmission. In this work, we have developed an empirical expression for the input impedance of a rectangular microstrip antenna. To imitate the broken situation of the conductive threads of the wearable antenna, a stripground design of rectangular patch antenna with the conventional substrate is presented to investigate the change of the antenna performance, where the ground is sliced along its plane. Design of rectangular microstrip patch antenna part 1. Due to the imperfect value of the graphs11 and vswr value graph we obtained from the last discussion,we had been make some effort to optimize it during week 11 meeting. Designing a patch antenna has some concepts and mathematical equations. The rectangular patch is implemented in the top metal layer and the ground plane in m1.
The microstrip patch antenna calculator determines the length l and width w of a rectangular microstrip patch antenna for a given resonant frequency or vice versa. Design of rectangular microstrip antenna 4 rectangular microstrip antenna simulation in visual basic the rectangular microstrip antenna patch was designed in matlab and the design program converted to a function of resonance frequency, dielectric constant, substrate height, and the desired input impedance zin. Rectangular, single polarization microstrip antennas. Deschamps in 1953, but didnt become practical until the 1970s when it was developed further by researchers such as robert e. Selecting best feeding technique of a rectangular patch. The microstrip antenna can be thought of as a rectangular cavity with open sidewalls. Analysts finite element wave ports are used to drive the antenna and radiation patterns and feed return loss and input impedance are calculated. Coaxialfed rectangular patch antenna lumerical support. Topics include principles of operation, impedance matching, radiation patterns, circular polarization, bandwidth, efficiency, alternative feed types, stacked patches and higher.
The width of the antenna, w, on the other hand, determines the level of the input impedance. Microstrip antennas are becoming very widespread within the mobile phone market. The parameter specifications of rectangular microstrip patch antenna are mentioned in table 1. The goal is to match the input impedance zin to the transmission line z0. Suppose we have a rectangular patch antenna, which is formed by fabricating a rectangular metallic patch on a dielectric coated ground plane. Input impedance of rectangular microstrip patch antenna with. The frequencydependent characteristic impedance included in. A microstrip patch antenna is a planar directional antenna in which a metal patch is placed on top of a dielectric substrate which in turn is placed on top of a metal ground plane. Jan 04, 2017 design of rectangular microstrip patch antenna part 1 matlab calculation duration. This optimal point can be calculated from the standard impedance 50 ohm and length of the designed patch antenna. Firstly, we will present the notion of impedance matching and its different methods. International advanced research journal in science. So, in this video, im going to show you how to design rectangular microstrip patch antenna. In this work, the simulation tool of ie3d is used to study the performance and gain of the rectangular microstrip patch antenna.
Hfss design of rectangular patch antenna using microstrip. Analysis and design of rectangular microstrip patch. These are calculated from the above discussed formulae. Microstrip patch antennas or simply patch antenna are increasingly useful because the antenna is printed directly onto a circuit board. 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 control the polarization, or for convenient layout. The purpose of this paper is to design a microstrip rectangular antenna in advance design system momentum ads. For a rectangular microstrip antenna, this requires the length of the antenna, l, to be about half a wavelength in the dielectric medium. Design a rectangular microstrip patch antenna for wlan. First the model of the microstrip patch antenna has to be drawn in hfss. The rectangular patch is by far the most widely used microstrip antenna configuration. In general, the characteristic impedance of a transmission line is 50 ohms. This work analyses the performance of different feeding techniques for rectangular microstrip patch antennas used in wireless communications applications, such as in wimax and lte technologies. The design procedure started with the design of a single.
If the ratio lw is close to unity, the radiation pattern will be symmetric but may not provide a resonable input impedance. In addition, by adding loads between the patch and the ground plane, such as pins and varactor diodes, adaptive elements with. A circular patch antenna utilizing the proposed 90deg broadband balun is shown to attain measured impedance s 11 antenna. Additional benefits of patch antennas is that they are easily fabricated making them cost effective. Regarding the circular patch antenna, of radius a, the resonant frequency can be calculated using. The basic principles are illustrated here for a rectangular patch, but the principles apply similarly for other patch shapes. Three types of feeding arrangements are discussed here.
Rectangular patch an overview sciencedirect topics. This paper presents the design and simulation of rectangular microstrip antenna rmsa arrays for improved gain performance over the single element rectangular microstrip antenna. The input impedance and vswr, return loss have been measured with the help of network analyzer. Design of rectangular microstrip patch antenna part 1 matlab calculation duration. This example demonstrates the use of a coaxial probefed rectangular microstrip patch antenna. Hshaped slots formed by cutting three slots from a rectangular patch 4, 5 due to which gain and bandwidth of micro strip antenna enhanced. Microstrip or patch antennas are becoming increasingly useful because they can be printed directly onto a circuit board. Slot antenna differs with patch antenna in many aspects.
Feb 16, 20 substrate patch a substrate coaxial ground plane connector bfigure 2. In our project, we used microstrip line feed which is a feeding method where a conducting strip is connected to the patch directly from the edge. 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. So, input impedance is a critical parameter for design a patch antenna. The rectangular microstrip antenna patch was designed in matlab and the design program converted to a function of resonance frequency, dielectric constant, substrate height, and the desired input impedance z in. Design characterization of rectangular microstrip patch. Patch antennas are low cost, have a low profile and are easily fabricated. Threeelement vectors of cartesian coordinates in meters. Design and simulation of rectangular microstrip antenna. However, previous studies abstractin this paper, a simple design of wideband rectangular patch antenna is presented by using asymmetrical feed and a reduction in ground plane with proper gap distance.