It has been observed as the slot length increases the resonant frequency shifted to the lower side by 19. Here is an example of an artificial ground plane added by someone to an 8 dbi 2. Patch antennas come in various shapes and sizes and consist of a patch of metal directly above a ground plane. As the name indicates the antenna ground plane acts as a simulated ground. Planar antennas, including microstrip antenna, printed antennas and metalplate antennas are. The uniform geometrical theory of diffraction gtd is employed for calculating the edge diffracted fields from the finite ground plane of a microstrip antenna. Our antenna design reflects innovative ideas and modern antenna fabrication. The radius of the circular monopole disc is the first parameter to optimize for the lowest return loss and widest bandwidth while the other parameters are. I have looked online a bit and it seems to me that the general belief is that the larger the ground plane up to a certain extent, the better. As the name indicates the antenna ground plane acts as a. The microstrip dipole antenna with rectangular ground plane of dimensions length l1. Thus, it is necessary for an antenna designer to understand the effects of the ground plane on antenna characteristics in order to be able to choose a ground plane.
If it were any smaller, it will start to reduce the bandwidth at the input. To investigate the effect of the ground plane size on the radiation characteristics of an msa, a conventional msa with a full metallic ground plane that operates in the dominant mode tm. Actual environments are different, and the ground plane is necessarily limited. The antennas feed is a through hole and reaches the bottom of board, where it meets a 50 ohm transmission line. The patch is attached to the ground plane by foam, providing firm connections and flexibility in bending. Abstractthis paper presents the effect of the slots in ground plane and patch on resonant frequency, impedance bandwidth, gain and side lobe. Effects of ground plane size on antenna gain electrical. What is the optmized size for a ground plane for micro.
The thickness of the ground plane or of the microstrip is not critically important. This paper presents the effect of the slots in ground plane and patch on resonant frequency, impedance bandwidth, gain and side lobe. The fringing fields around the antenna can help explain why the microstrip antenna radiates. The design and analysis of printed antenna with the reduced ground plane effect, fed by micro strip line for ultra wide band uwb communication systems is presented. The effects of ground plane size on the characteristics of a square microstrip patch antenna designed on a lowpermittivity substrate with an air gap. The finite ground plane effect on the microstrip antenna. This assumes that there are no earth or grounding losses. The vertical element and radials are 332 or 116inch brass welding rod. To improve the gain, ground plane dimensions length and. The effect is shown on bandwidth, gain, radiation pattern, return loss, axial ratio and size of an antenna.
Note that since the current at the end of the patch is zero open circuit end, the c. Patch antennas can show a very high gain, especially if they are mounted on top of a large ground plane 70 x 70 mm. I currently work for a different company that makes electronics with gps patch antennas in them. By the end of this post, youll know the factors in your design that determine whether you need a directional antenna. These antennas are available with unity or 3 db and 6 db gain. The antenna is designed following the conventional design steps by applying duality theorem to it. The effects of varying the size of the ground plane of a rectangular microstrip antenna, which can excite te modes, are investigated in this paper. For example, some patch antennas are approximately half a wavelength on each side. The ground or reflector seems to be about 12 inches square, as the 8dbi patch is 4. Effect of partial ground plane removal on the radiation. An improved uwb patch antenna design using multiple notches. If the ground plane is too small, the antenna shifts frequency, and thatll kill your sensitivity much more than the patterns going askew. Abstract in this article a broadband microstrip patch antenna is designed with slit incorpo rated in the rectangular ground plane. Good design practice is to have a threeelementmatching network going into the feed, to give some additional tuning ability if required.
This paper presents effect of slots on microstrip patch antenna and its parameters. The partial ground plane removal reduces the backlobe radiation of. This is usually achieved with radials, either attached to the base of the vertical, or buried below a ground mounted antenna. Effects of using different substrates on the performance. It has been observed as the slot length increases the resonant frequency shifted to the. Various models of gp antennas having wider bandwidths than specified can be designed and supplied.
Effect and design of microstrip patch antenna with defected ground structure. The third antenna is designed by stacking another similar hexagonal patch on top of the hexagonal patch antenna with slot in the ground plane and the feed location is optimized. The patch is of length l, width w, and sitting on top of a substrate some dielectric circuit board of thickness h with permittivity. Previously, chen et al 8 have described a small printed antenna with reduced ground plane effects for uwb frequency ranges.
The operating principle of these multiband antennas is based on multiple resonances of different parts of the antenna structure, including the ground plane of the printed circuit board pcb. In this paper we have introduced a new concept of strip lined truncated ground plane for inset fed microstrip patch antenna. Its good to have 1 wavelength ground plane size, but half wave. Download citation effects of ground plane size on a square microstrip patch antenna designed on a lowpermittivity substrate with an air gap the effects of.
In proposed antenna, the ground plane is considered to be the half of the substrate. The effects of ground 33 with its four groundplane radials elevated well above lossy earth. The slots on the patch or on the ground plane will help to design a. Consider the side view of a patch antenna, shown in figure below. Effects of ground plane size on a square microstrip patch antenna designed on a lowpermittivity substrate with an air gap, 2010 international workshop on. The efields at the edges of the patch undergo fringing effects.
As this antenna can only radiate above the ground plane, a monopole antenna will have a gain of 3 db over an equivalent dipole. With dipoles, one half of the antenna is your ground. Design and improvement of microstrip patch antenna. Patch and ground plane design of microstrip antennas by. This type of study is useful to design the compact antennas for mobile communications. Effect of slots in ground plane and patch on microstrip. The bent monopole antenna on the nordic board has an omnidirectional antenna pattern, whereas a design that requires a directional antenna might place the antenna directly over a ground plane. The antenna is designed following the conventional design steps by applying duality theorem to it in order to excite the te modes. He said it is 12 inch behind the patch mounted with insulated plastic. I understand that a patch antenna has a radiation pattern similar to the following picture from wikipedia when the patch antenna is centered over the ground plane. What is fringing effect in microstrip patch antenna. Patch antenna parameters variation with ground plane dimensions.
The horizontal radiation pattern is a circle where the antenna radiates equally well in all directions. I used to work for a company that made electronics with gps patch antennas in them. Design of slotted ground hexagonal microstrip patch. This study presents a new, simple method for reducing the backlobe radiation of a microstrip antenna msa by a partially removed ground plane of the antenna. My understanding is that when building or installing an antenna designed to operate over a ground plane e.
The magnetic conducting patch and ground planes replace the electric conducting patch and ground plane. Patch and ground plane design of microstrip antennas by material. Most radiation analyses of microstrip antenna are based on the assumption of an infinite ground plane. In general, the ground plane size of the patch antenna should be 23 times the patch size, so as to maintain a good front and rear ratio. The simulated results indicate that by cutting an elliptical patch at radiator, the proposed antenna yields a wide operating bandwidth of 2. Quarterwave antenna antenna on a ground plane signal generator image conductor gnd plane return current length. In this paper, we show the influence of the dimensions and the shape of the support. Ground mounted antennas are often very easy and convenient to use.
This antenna is often built of printed circuit board material and the substrate makes up the patch antenna s dielectric. The basics of patch antennas, updated orban microwave. The patch antenna, microstrip transmission line and ground plane are made of high conductivity metal typically copper. The antenna configuration in figure 1a is first used for the parametric study. Selecting the right antenna gain for the application is the subject of much analysis and investigation. It has been observed as the slot length increases the resonant frequency. Adding a ground plane to your pcb is a simple, lowcost, highly effective way to design electronic devices that have better signal integrity, higher accuracy, and more resistance to interference. An illustration of the filtering effect on the design. I am trying to design a patch antenna, so i ran several fullwave simulations and increased the ground plane size each iteration, extracting the gain. An inset fed rectangular patch antenna is designed to operate at 2. The gain of an omnidirectional antenna can be increased by narrowing the beamwidth in the vertical or elevation plane.
The antenna system requires a ground plane for the radio wave to form. I am designing a four layer board in which a patch antenna is used for a gps receiver. The distance between the patch and the ground plane the substrate or dielectric height h determines the bandwidth. Fig25simple groundplane antenna for the 144, 222 and 440mhz bands. While they have less reduction of rearward radiation than a larger design, they still have useful gain and directivity. Whats the difference between a dipole and a ground plane. Many numerical and measured results are presented to demonstrate the accuracy of. In the antenna in figure 1, the center conductor of a coaxial line serves as the feed probe to couple electromagnetic energy in andor out of the patch. Patch antenna ground plane effect on radiation pattern. The effect of the partial ground plane removal in different configurations on the radiation characteristics of a msa are investigated numerically. Citeseerx document details isaac councill, lee giles, pradeep teregowda.
Effects of ground plane size on a square microstrip patch antenna. Study the ground plane effect of a multiband antenna for. Currently, there are considerable research efforts directed to the compact multiband antenna design and many designs have been proposed 810. Sec antenna manufactures ground plane and marine gp antenna. The size of the ground plane of your embedded antenna will effect the performance.
The fundamentals of patch antenna design and performance. The planar circular disc monopole is fabricated on a 3 cm 5. However when it is not possible to ground mount an antenna because of ground conditions or it is necessary to elevate the antenna, another solution is to use a ground plane. Bandwidth enhancement of uwb microstrip antenna with a. An elliptical patch uwb antenna with reduced ground plane. Effect and design of microstrip patch antenna with. I observed that as i increase the ground plane size, the gain increases at first and then decreases. One familiar application of this type of patch antenna is the. In verticals, something below must provide ground to complete the rf wave. If youre not in the habit of incorporating a ground plane, make sure to keep these benefits in mind when it comes time to lay out your next board. Effect of ground plane size on a rectangular microstrip. Citeseerx effect of strip lined truncated ground plane. The main disadvantage of these antennas is their relatively large size compared to other types of antennas. As we know the current distribution on the ground plane of the conventional patch antenna mainly concentrates.
Ceramic patch antennas are very popular because of the low costs and the huge variation of available sizes 40 x 40 mm down to 10 x 10 mm. It is possible to simulate this function by replacing the real earth. The proposed antenna is design ed by using fr4 substrate with. Influence of the ground plane structure on the radiation. In this article a broadband microstrip patch antenna is designed with slit incorporated in the rectangular ground plane. The image is a tool for understanding the earths effect on patterns. It is found that for a monopole antenna like a quarter wavelength vertical, the ground acts as a plane to reflect the radio waves so that an image of the top half of the antenna is seen in the earth.
The ground plane required on one side of the antenna is approximately 20 mm wide. The microstrip antennas have been designed on er 4. Design of microstrip dipole antenna at various ground. Study the ground plane effect of a multiband antenna for multiple. The developed antenna was found to operate at an uwb frequency of 10. The photograph of the fabricated antenna is shown in figure 6a while the reflection coefficient measured and simulated is shown in figure 6b.
The simulation results show that the gain of a circular patch antenna varies with the ground plane size. The bottom of patch is filled with ground but the layer adjacent to the ground filled layer is a power plane. In the introduction it was mentioned that the enclosure and the components close to the embedded antenna like battery or display will interfere. The source field from the radiating patch is calculated by two different methods. The effect of simulated return loss, swept gain and rad iation pattern of the proposed antenna have been obtained due to variation of slit dimensions. A microstrip patch is a form of a narrow band with a wide beam antenna, which can be described simply as being made up of a metallic radiating patch and a ground plane each one at one side of a dielectric substrate and a feeding point which can either be connected to the radiating patch directly or indirectly, depending on the feeding method used. Since the image is 180 degrees outofphase with the antenna and effectively the same distance below ground as the antenna is above ground, it becomes obvious there will be a null along the ground with a horizontally polarized antenna. The original design and its ground plane effects will be. How will the ground plane effect your embedded antenna. The resultant value of bandwidth and return loss is 545mhz and 60. See chapter 6 for more details on practical groundplane verticals.
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