A typical mobile cb antenna does not transmit horizontally, it radiates in a downward pattern. In this paper, we present two techniques to enhance the. For efficient transfer of energy, the impedance of the radio, the antenna and the. Slotted ground plane of rectangular patch microstrip antenna. The antenna is unaffected by either and i have used both at different times. A ground plane antenna is a variant of the dipole antenna, designed for use with an unbalanced feed line such as coaxial cable. Index terms directivity, far field, finite ground plane, monopole antenna, radiation pattern. Gps microstrip antenna array on a resistivity tapered ground plane for multipath mitigation basrur rama rao, the mitre corporation jonathan h. This limitation introduces significant errors into the measurement as a result of truncation of the nearfield data and other ground plane effects. Gp 450 is a ground plane antenna of the tripleleg type. Pdf effect of slots in ground plane and patch on microstrip. In telecommunication, a ground plane is a flat or nearly flat horizontal conducting surface that serves as part of an antenna, to reflect the radio waves from the other antenna elements.
A groundplane antenna is more of less one half of the dipole and mounted above the ground plane. Concentrated ground plane booster antenna technology for. Tv antennas free delivery possible on eligible purchases. Predict accurately the hplane amplitude pattern of rectangular and circular apertures mounted on a ground plane with straight.
The position of the antenna mounting is crucial for an optimal performance of the gps receiver. In my own situation i secured two aluminum straps that were bent in a lazy s shape and screwed the free ends of the straps to a solid portion of the house. Pdf a simple rectangular microstrip antenna with triangular slotted ground plane. Slotted ground plane of rectangular patch microstrip antenna with enhanced bandwidth and size reduction soliman a.
The final on air test was what the s meter reading would be for the vk6rec repeater that had usually presented an s3 signal for the 146mhz 58 ground plane antenna. For a horizontallypolarized antenna, the hplane usually coincides with the verticalelevation plane. The firestik fg2 2 foot nogroundplane replacement antenna comes in black or white and will replace a broken or damaged antenna from one of firestiks kits. The flat type antenna has a compact structure and the total size\r\nis 14. This was not entirely surprising as the there had been some antenna modelling done by others that suggested that the 58 ground plane offered little if any advantage over the simpler 14 wave ground plane as a tower mounted antenna as i was utilising them. Dec 30, 2015 another little application written to help aid in vertical antenna construction. The ground plane boosters proposed here are solid metallic structures featuring a cube shape and connected with.
You might want to get a couple of them just in case you damage it on the first try. This conductive mechanical device is the transducer that converts the radio. When using patch antennas, the antenna plane should be parallel to the geographic horizon. A simple ground plane antenna you can buildfor 146, 223 or 440 mhzin no time flat. An efficient vertical antenna, such as a medium wave broadcast tower might appear to work off the earth ground however it most likely has conductive radials buried just below the surface the number of them and the. Whats the difference between a dipole and a ground plane. You have an ineffective antenna it does not radiatereceive well. The model i rarely build any hf antenna unless i model it first. The amountsize of the groundplane required for the optimal performance of a monopole antenna is determined by the frequency you are transmittingreceiving at. A ground plane antenna removes half the dipole and substitutes the ground plane for that. Gps microstrip antenna array on a resistivity tapered. A monopole over an infinite ground plane is theoretically the same identical gain, pattern, etc. Radial attach each radial with a 632 screw, lockwasher and nut 20. This was not entirely surprising as the there had been some antenna modelling done by others that suggested that the 58 ground plane offered little if.
A metal surface the larger and flatter, the better is required underneath the cb antenna to launch the signal out into the atmosphere. A typical 58 wave antenna at 150 mhz requires a ground plane at least 42 in diameter. The ground plane as described should as easily be used on 220 or 440 mhz without modification, although if you use it only on those bands, you could save some realestate by. Every ham likely has made a 2 meter antenna from a discarded cookie can or a pizza pan. Create antenna on infinite ground plane create a patch microstrip antenna on a ground plane of infinite length. The microstrip dipole antenna with rectangular ground plane of dimensions length l1. Slotted ground plane of rectangular patch microstrip. 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. Rama rao is a principal engineer at the mitre corporation.
About ground plane for 7 mhz the resource is currently listed in in 2 categories. A groundplane antenna is a form of dipole antenna designed to work with an unbalanced feed line. For a horizontallypolarized antenna, the h plane usually coincides with the verticalelevation plane. A dipole antenna is effectively a resonant length of wire broken in the middle to allow the feedpoint to be inserted. Quite often a vertical antenna or a random wire is one side of the antenna and the earth ground is the other a flat plane. Buy failsafe 14 wave professional grade tunable ground plane antenna. Here is the list of parts needed to build your own quarter.
Indoor and outdoor measurement ranges which provide free spacelike conditions for the antenna are. Every time you increase the power by a factor of 2 times, you have a 3db in. The proposed antenna is\r\neasy to be integrated with microwave circuitry for low manufacturing\r\ncost. The new 14 wave ground plane antenna received the vk6rec repeater also at s3. Simple 2 meter ground plane antenna project with pvc support by kc0ynr, malcolm here is a very simple 2 meter ground plane project that can be used as an emergency antenna, in limited space, for quick and easy setup on field day, camping, or just plain outdoor fun. Slots are incorporated in ground plane of a simple rectangular patch antenna designed in cband on fr4 substrate with dielectric constant. Chapter 7 is focused on the techniques used to measure antenna parameters. A ground plane antenna is a form of dipole antenna designed to work with an unbalanced feed line. Use tape to hold the parts on the noncopper side together and fold the corners to they met. The antenna is delivered in two models tunable over the ranges 380430 mhz l and 420470 mhz h, respectively, by adjusting the length of the radiator. Download software 14 wave antenna with ground plane. The cutting diagram on the diagrams tab indicates how long the radiator must be corresponding to a specific centre frequency. However, the number of other ops on 6 meters has the tendency to be small, so a beam will give you better odds when openings come. Ideally for radials you should have them sloped downward at a 45 degree angle to help provide a better match.
It is possible to simulate this function by replacing the real earth. The electric field or eplane determines the polarization or orientation of the radio wave. The magnetizing field or hplane lies at a right angle to the e. Each srr is separated by a distance of 30 mm along both the x and y directions. The drop off on the horizon is only a db or so and insignificant. Radial slowly twist the wire while pulling it to keep it taught.
Your bike unless its a very small miniscooter or pocket racer less than 30. A close look at this familiar makeshift antenna may surprise you. Before starting to build the antenna, you can stiffen up ordinary 14 gauge copper. A groundplane antenna is a variant of the dipole antenna, designed for use with an unbalanced feed line such as coaxial cable. Aug 04, 2008 a 6 meter 14 wave ground plane is an easy antenna to build, and if you can give it some elevation will perform fine for you. Firestik firefly lg3m2lg4m2 noground plane cb antenna molded side mount kit from.
Place the active antenna on top and solder a small wire from the aluminium cage on the antenna to the copper of your. Here is the list of parts needed to build your own quarter wave ground plan vertical antenna. The radiation pattern properties and some simple design procedures are explained. If you omit the ground plane from a ground plane antenna, then there are only two possibilities for what happens. Pdf modified ground plane of patch antenna for broadband.
Analysis of the effects of rectangular ground plane on. The polarization of an antenna refers to the orientation of. The radio waves from an antenna element that reflect off a ground plane appear to come from a mirror image of the antenna located on the other side of the ground plane. The plane does not necessarily have to be connected to ground. The ground plane may be the bodychassiscircuit board of the transmitter, or for more predictable results, a sheet of conductive material under the single wire antenna, or often several lengths of wire a quarter wavelength long connected to the screen of the coax cable connecting to the antenna. Model infinite ground plane for unbalanced antennas.
Neither will i recommend one to others without being able to show the theoretical performance in a computer model. Instead use 440 bolts home depot and the 440 nuts to fit them. Prttern 0 10 60 iiiiiiiiiiiiiii 90 70 50 30 10 10 30 50 70 90 scan angle deg figure 8b. The pipe can then be secured as one might wish and the coax run to the entry point to the station. Introduction onopole antennas are half the size of their dipole. When mounted on the 4radial portable ground plane described above, the same antenna shows 1. Enter the frequency in mhz and click calculate it will give you the length for the radiating element as well as the ground plane elements. Blog antenna ground plane calculation arcadian antenna.
Ease of fabrication and cost makes the ground plane antenna one of the popular antennas in communication systems. Antennas on high impedance ground planes citeseerx. Antennas 101 11 the basics 7 gain measures redistribution of energy gain is a comparison of antennas gain is always with respect to a reference dbi isotropic, dbd free space 2 dipole 2 dipole has 2. Part of omnidirectional cellular antenna design is a ground plane or metal that reflects signal into the antenna itself many antennas have a ground plane built in, but in particular magnetic mounted antennas often kitted with mobile boosters require one be provided. Vhf and uhf antenna systems 1821 fig23these drawings illustrate the dimensions for the 144mhz ground plane antenna. As the name indicates the antenna ground plane acts as a simulated ground. The presence of the ground plane limits measurements to one hemisphere or less about the device under test. In proposed antenna, the ground plane is considered to be the half of the substrate. Ease of fabrication and cost makes the groundplane antenna one of the popular antennas in communication systems. Ground plane availability is another critical factor in mobile antenna performance and must be considered when determining the location and type of the antenna. The magnetizing field or h plane lies at a right angle to the e plane. Here is the free space wavelength corresponding to the resonant frequency of the srr array which is 950 mhz. Pdf biconical antenna over ground plane researchgate. A 6 meter 14 wave ground plane is an easy antenna to build, and if you can give it some elevation will perform fine for you.
Ground plane requirements vary given the type of mobile antenna and the frequency of operation. Item 1 generally comes under the topic of tuning, where you bring the antenna into resonance or wherever it was designed to be tuned. A microstrip dipole antenna with rectangular ground plane is shown in figure 4. You can pick one up at radio shack or your favorite electronic supply. So here is the model for the k8ch antenna, modified and scaled for 20m. In this paper, we present two techniques to enhance the bandwidth and reduce the size of microstrip antenna. An antenna ground plane is not to be confused with an electrical ground. This is a piece of wire extending over the pcb in free. The electric field or e plane determines the polarization or orientation of the radio wave. When 8 radials are used instead of 4, the swr improves to 1. Study of the quarter wave vertical 20m antenna with.
V antenna, yagiuda array, turnstile antenna, helix, spiral, microstrip patch, etc. The everhardt sngp4 4 foot nogroundplane antenna kit is made to solve the problem associated with lack of ground plane on fiberglass or aluminum vehicles such as rvs. The resultant value of bandwidth and return loss is 545mhz and 60. It features wireend loops for safety sharp, straight wires are hazardous and convenience its top loop lets you hang it off high objects for best performance. Quick view firestik fg3 3 foot black or white nogroundplane replacement antenna. Design of microstrip dipole antenna at various ground plane.
Nsimi technologies ground plane data simulator software provides the capability of. Study of the quarter wave vertical 20m antenna with elevated. The antenna wire frame and its elevation pattern are shown in figure 1. The antenna consists of a square patch, a partial\r\ nground plane and a slot on the ground plane. Antenna ground planes for rvs and boats mobile internet. The main category is antennas for 40 meters band that is about 40 meter band antennas projects. This link is listed in our web site directory since monday jul 21 2008, and till today ground plane for 7 mhz has been followed for a total of 2961 times. Plane wave with polarization along ydirection is incident along negative zdirection. Antenna design and rf layout guidelines cypress semiconductor. Ground plane and antennas electronics forum circuits. Simple ground plane antennas n1gythe simple approach to. I dont recommend soldering the ground plane radials. Pdf a bicone over a finite ground plane is designed that has on average 2. A ground plane antenna is more of less one half of the dipole and mounted above the ground plane.
Now cut the required part until it looks like the following picture. This example shows how to model an infinite ground plane and calculate fundamental antenna parameters for unbalanced antennas. In this case, its a multiband antenna the customer is using it can be used from 700 mhz 2700 mhz so the ground plane required could be anywhere from 464 square inches. Vhf adjustable ground plane 1186mhz gp3 the gp series is a range of omnidirectional unity gain adjustable ground plane antennas ideal for local area coverage when a high gain antenna is not required or justified. A vertical element and a ground plane is just one possibility for what those two halves can be. The radiation patterns of eand hplane for a corrugatedtype antenna follow the general cmpa and the gain of the linearlypolarised antenna is 6. By john portune w6nbc the whip was a piece of coat hanger soldered into a banana jack, or a 19. Another little application written to help aid in vertical antenna construction. Groundplane antennas for 144, 222 and 440mhz for the fm operator living in the primary coverage area of a repeate r, the ease of construction and low cost of a 14. Failsafe 14 wave professional grade tunable ground plane. In the ground plane antenna style whip antenna, the plane consists of several wires. To ensure maximum power transfer from the source to load through rf. It resembles a coaxial antenna whose lower section consists of straight elements called radials instead of a hollow conducting cylinder. A key to realizing highgain, cross polarizationfree microstrip antenna with improved bandwidth.
897 152 1171 1098 335 868 1147 806 1347 374 1264 1230 3 356 552 805 806 784 104 148 562 667 1037 1586 1485 547 1080 1394 372 1320 280 1324 846 268 230 778 830 394 1272 266 317