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321 Threads found on Directivity Antenna
What is different between isotropical and directivity antenna? thanks
anybody can give me some detail about st330.this is a kind of directivity antenna which design by Radio Frequency Systems.and i want to simulate it in supernec,but i don't know the size ,who can tell me?thanks!
Hi, Can somebody give some suggestions on any planar antenna designs which have a very good directivity i.e. farfield radiation focussed in one direction. thanks in advance. regards, abti Hi abti Could tell us what you means the"high directivity"of planar antenna.The limit directivity of (...)
The gap between high mm-wave band and far infrared is today a hot topic (0.1-10THz)! Usually, if you have a single antenna, lens is the approach you should go for in case you need high-directivity antenna. One of (many) problems is the reflection on the lens-air interface. EDIT: "patch antenna" ... you mean planar (...)
How many ways we can measure the gain of antenna. What is the best method to measure the gain of antenna? Gain=f(eff,directivity) :!: :idea: :?:
Such as Impedance vs Frequency directivity pattern Elevation pattern Radiation impedance vs. wavelength Others
Dear Rayengine! If we consider lambda/2 dipole for example, it has directivity 2.15 dBi. Monopole with infinite ground causes radiating only to upper half space, so that directivity of monopole=directivity of relevant dipole+3dB In our case of lambda/2 dipole, its counterpart is lambda/4 monopole with D=2.15dBi+3dB=5.15dBi In prac
Dear Lupin, I need to calculate the directivity of linear and planar array. I have already calculated array factor. Can you help me in matlab. I will be very thankful to you
Hi Fellows, I am working on the design of an horn antenna. I have designed a horn antenna operating at 8 GHz frequency. directivity achieved with this antenna is 18dB. and a beamwidth of 22 degrees. I want to know, is the gain same as the directivity of the antenna. What is the (...)
hi,interested paper to modify the gian and directivity of yagi antenna using log periodic technique. i hoe enjoy special thanks to dr.hassan sallabi to help me. pls thanks him
Hi, Do anybody know how to measure gain of an antenna? I am using Pringles can antenna, but not sure exactly what gain I am getting out of it...Plz help if you can Thanks Mitesh Hi! directivity of this type of antenna is around 8dBi. So the gain is slightly lower, you can count with 7dBi. Regards, eirp
Hi, I'm involved in a study of linear and planar phased arrays. I'm looking for formulas of directivity. I've been writing a code. The general formula of the directivity must be checked for particular cases (uniform array..). Can u help me? Thanks in advance Lupin
i just begin to do some job in this field, i want to know what should be considered when choosing the mobile antenna.thanks the gain ,the size ,the shape ,the weight&the directivity
If the radiation patter of an antenna is cos(Teta) normaly it means that the directivity is >1, so use tu be A*cos(Teta) with A>1... All non omnidirectional antena has a directibity > 1 So D1
The basic concepts in antenna measurements are presented in this module. First, a brief description of antenna ranges and anechoic chambers is given. Second, the basic methods for measuring the far-field radiation patterns, the gain, the directivity, the radiation efficiency, the impedance and the polarization are discussed.
I used the version 3.0 and there was sonething to be improved..I mena for instance directivity computation... I've no idea about the 4.0..does anyone have comments? I agree, a trial version could help us. Regards Lupin
Not only microstrip antennas have been constructed on a PCB. I've heard that a complete Yagi (5 or7 elements) can be constructed on a PCB. Does anyone have the plans for a 5 or 7 element Yagi working at 915MHz? I'm also interested on any other antenna type that can be printed (but needs to have large gain and directivity). Thanks all.
max232, The problems that you can get designing a PIFA for mobile depend by your system requirements: dimensions, directivity, bandwidth, gain, etc. Must be finding the compromise among antenna dimensions and radiation characteristics. Modifying the antenna geometry lead to smaller size. Inserting slots force the surface currents to (...)
Passive, the gain you get is relative to either an isotropic(dBi) radiator or dipole(dBd). Should think in terms of directivity instead og gain.
antenna gain is often quoted as EIRP, that is "Effective Isotropic Radiated Power", or the apparent power transmitted assuming that the antenna radiates equally in all directions, IE. the field is assumed to be spherical from a point source with an equal power transmitted in all directions. EIRP is the product of Power supplied to the (...)
Hi, I need help to simulate an antenna (extended inner conductor coaxial antenna) as shown in the figure (Fig2). It should give properties similar to a 2-wire dipole antenna (radiation pattern, S11<-10dB, etc). I've tried to simulate in HFSS. But i cannot get a compromise between low reflection loss and a 90degree (...)
anybody know the st330 antenna.the antenna is design by Radio Frequency System. in many book,the sloping wire can get omni-directivity pattern.why the antenna st330 can have directivity? how they do it? who can tell me? and i want to know the value of the terminal.thanks!
Dear All Please I am a master student in iraq I am studying on Rectangular Micro strip antenna but I met many problems in (Radiation pattern, Input impedance, Radiation power, directivity, Energy stored, Q-factor, Input conductance, Gain, Efficiency) because there is no new sources in iraq please are their any one can help me to send me any sear
Lets say I have a monopole antenna and S11 for this monopole is -5dB (in free space) over a certain frequency range. If I improve S11 from -5dB to -20dB over the same frequency range, would this be considered as a good improvement? In addition to the improvement in the S11, if I obtain 12 degrees of half power beamwidths both in E-pl
Have you tried to use Gain / directivity to calculate the radiation efficience? How is the result, still great than 1? Hi, Gain/directivity ratio was the first thing I looked at and as expected in this scenario, it is greater than one. By the way , seeding the mesh in the airbox to λ0/6 also did not help.
I hope to get some information about multi skirt antenna. I don't know the exact spell. It may be multi scot, multi scat, multi scott, and so on. I attach the shape I found and the directivity I want. The upper directivity graph is horizontal directivity. And the lower one is vertical directivity.
i simulate a gsm dualband helical antenna in hsff. but the peak gain and directivity computed by hfss is always below -10dbi, this is obviously wrong, and the radiated power always large than the accept power, how it can be? But the radition pattern and return loss seem to be correct. pls help me.
hello svarun, your question says "... how big is good enough?" and I ask you, good enough for what?. Be aware that the ground plane size gives you an additional degree of freedom, and making it larger or smaller you can control the antenna beamwidth, and therefore the directivity. If you want a directive antenna with low back radiation (...)
I can say we need more details about the required directivity in what application .. for simplicity why you don't try mono-pole antenna
HI backward radiation and forward radiation are related to main antenna lobe, forward radiation is the region were directivity (or gain) has its max value; "backfire","endfire" and "broadside" are also related to the maximal value of directivity; in particular endfire means that radiation is max on direction along the array, in (...)
Simply, gain is directivity minus circuit losses. If losses are negligible, then directivity=gain.
hello ,everyone. Recently I have used HFSS to simulate two kinds of antenna (helical and microstrip antenna),I found all the parameters like gain ,directivity,pattern are correct except the antenna efficiency ,which is always highter than 1. I was quite puzzled that it was obviously unreasonable for efficiency highter than (...)
obtain the gain/directivity with hfss and then use the formula G=4piAef/lambda^2
it is a group of anntennas . primary intention is to form high directivity or to achieve unidirectional casting based on phase relations, they are classified into two types i)endfire ii)broadside arrays A linear array of antenna elements which are spaced by lamda/2 apart and driven with alternating phases has its principle radiation maxi
I wold love to have derivations regarding loop antenna.the methametical derivations of its perametets like E & H fields ,Power ,directivity
Hi, Who can tell me how the Hfss caculate directivity? why the directivity is so little(<1) in simulated microstrip antenna? the directivity always should be more than 1,it's true? thanks.
Hi, There are many type of antennas in the world such as Dipole antenna, Monopole antenna, Patch antenna, PIFA (Planar Inverted F-type antenna), Slot antenna, CP (Circular polarization) antenna and so on. Are there any web-sites or papers or books that introduce those (...)
dBi as an antenna measurement mean's dB over isotropic. An Isotropic radiator is an antenna that radiates equally in all directions. In other words, the radiation pattern look's like a perfect sphere. Because antenna's are directional, the antenna directivity is measured as the peak of the radiation (...)
you may also think about a printed dipole array above a reflecting plate. the directivity may be lower than a patch, but won't have the same bandwidth issues as noted by flatulent. cavity distance will be relative to the wavelength in the dielectric, so size must be considered.
hi freinds i need program with matlab for antenna simulation that in first of program get "L" and give "E" and "H" and drawing "E" and "H" and get "f" and give antenna pattern 1D and 3D and get maximum input current (phase and amplitude) and give "radiated resistance" and directivity and drawing current of (...)
hi freinds i need program with matlab for antenna simulation that in first of program get "L" and give "E" and "H" and drawing "E" and "H" and get "f" and give antenna pattern 1D and 3D and get maximum input current (phase and amplitude) and give "radiated resistance" and directivity and drawing current of antenna . and if (...)
The gain of an antenna takes account of the antenna efficiency as well as its directivity. The formal definition of gain in any direction is "power density radiated in that direction divided by the power density which would have been radiated at that direction by a lossless (perfect) isotropic radiator having the same total accepted input (...)
directivity of an antenna system towards a given direction(θ,φ) is the radiation intensity normalized by the corresponding isotropic intensity: D(θ,φ)=U(θ,φ)/Ui=U(θ,φ)=4πdP/PraddΩ Gain of an antenna system towards a given direction(θ,φ) is the total accepted power norma
Introducing the newest addition to the Diamond Engineering product line: the DAMS 6000 v5.0 antenna Measurement System Platform Features: - DC-18 GHz Frequency Range----->not new - Precision 2 axis Movement-------->Precision level?? - Accuracy to 1/8 of a degree--------> not good for high directi
Hi jian How can I put the directivity and gain in the same plot? THX PL
Hello everybody Can I build any of these components on board: - Coil - antenna (what about directivity and radiation pattern?) Please help me in it in some details Thanks alot in advance, Ahmad,
Hi, what kind of antenna parameters do you want to test? I think if you just want to measure the return loss (S11) or VSWR, then Network Analyzer is the only equipment you need. You just need to calibrate 1-port measurement of VNA, and then directly connect the VNA to your antenna, and read the S11 or VSWR from VNA. If you want to measure the
I'm a little confused, so Gain here is not the (maximum directivity)*eff, but is diff. from the direction: directivity(theta,phi)*eff. ??
antenna can be of "resonnant" and "non-resonnant" type. TV antenna is resonant. It is selective. antenna elements dimensions depend on frequency. But overall antenna dimensions depend ollso on parameters like wanted gain and directivity. Try to search forum on this topics and you will find a lot of (...)
directivity simly varies with size of antenna. You can have a look on small antennas fudamental limits regarding relations between antenna size and other parameters for a better view.