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Hfss And Lambda

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62 Threads found on edaboard.com: Hfss And Lambda
Hello. I did the design of the antenna with CST, but when I compare with hfss, I get a big difference of the reflection coefficient. What is the problem? Is it the airbox or the port or what?
Hello everyone! I made design of 5 x 5 TEM horns planar array in hfss, and found that there are the great back lobes (comparable -5, -6 dB to the main lobe) in all most frequency range. Element period in array < lambda (min). Has anyone seen this problem before? and how to fix it? I don't know where the back lobes come (...)
hello how could i evaluate S parameters (db S11 and S21 ) Versus Frequency plots in hfss.. regards Bukero
I modeled a microstrip patch antenna in hfss with airbox only lambda by 4 over the patch antenna. The airbox sidewalls and base touched the antenna, so none of the substrate edge scattering ripples are seen in the S11 results. I, then, fabricated the antenna and saw bunch of ripples in the S11 results, though the pattern (...)
I have designed a dual layer differential microstrip antenna .This is my first hfss simulation model and also I am very new to Antenna theory. This was designed based on a research paper . The model is running but the results aren't as they should be. (Like VSWR is highest at working frequency of 900 MHz; real and imaginary part of Z0 are (...)
Hi all i'm going to design an infinitesimal electric dipole above an infinite pec for height lambda/2.I'm going to earn figure 4.17 in antenna book,Balanis but the results aren't good at all.(VSWR and radiation pattern) i don't know how length i need for air gap in infinitesimal dipole?and don't know what is the problem? I'm using (...)
hello can anyone here please upload for me a layout for wilkinson power divider in hfss any design would be OK, i'm new to hfss and want to see how the layout looks like anyway my design is operating at 3GHz with equal P3:P2 lossy with lambda/4 matched Thanks in advance Hi, It's better if you can come with your la
Hy, I am a beginner in antenna propagation and hfss. I have a quesion about the monopole antenna. I fixed my antenna on a cylindrical Cavity build with a NEW material with relative permeabilty 1000. when I valdiate it does not display errors and when I click on analysis at the beginning it works then it stops doing in (...)
Hi friends, I have designed 3 rd order band pass filter in hfss. For short circuit stubs, i used a small cylinderical hole in hfss with radius as 0.4mm. Is there any standard formula or dimension ? Please guide me
1- radiation buondry means the space that you should define as a farfield area and make it as an radiation , so your device can radiate in far field. thid area should be more than 10*lambda 2- to calculate the equations, hfss has some passes, if the difference between two results in each passes is less than for example 0.02 (that yourself (...)
Hello, I am simulating some lambda/2 series CPW resonators, and have been getting some disagreement between my results when simulating by Wave Port or Lumped Terminal. They both show resonance at roughly the expected frequency, but disagree on order of a few hundred MHz. I am inclined to believe the wave port results as they are close to ADS Mo
I can confirm that in hfss for eigenmode simulation of planar structures, having the PML 1/4 of a wavelength from the structure gives the same results (or as much as is discernible) as having it to within 1/30 of a wavelength. As far as I can tell from the information provided, your setup looks correct.
@anvc - This sounds like a problem with mixed units or improper setup. A simple dipole should not take more than a couple of minutes to solve. Even though the structure may be large in physical size (17 cm), it should be reasonable in electrical size (lambda/2). Check to make sure your units are correct, and that your analysis frequency is appropri
hi all, i was trying to simulate a simple monopole on hfss. however, when i was doing the simulation, i noticed that the length of the monopole doesn't exactly follow the lambda/4 eqn; the resonant frequency seems to be 2 or 3 times higher than the antenna was designed for. i think it has to do w/ the radius of the monopole, as well as the size o
Hi All, I'm working on ungrounded CPW structure. I've been through all previous post about CPW , how to feed it and Ansoft tutorials,and I designed a cpw antenna with SMA. From Antenna_kit released by ansoft I realized that the length of the coax should be lambda/6. So I simulated my CPW with 4 different feeding, 1.SMA with (...)
But the standard method in hfss to analyse an antenna is to put it in a box which is lambda/4 away from the antenna - they call it an airbox. Outside the airbox is a perfect electrical conductor. PEC for sure? Does that make sense? All 3D solvers that I have worked with use absorbing boundaries for
1. If I am going to have a receive antenna in simulation model, why do I need a radiation box? The radiation box measures the power radiated, gain, the far field, but what if I have an antenna in far filed to measure all that? 2. Also, the minimum radiation box size of lambda/4 is not in the far field since minimum distance in f
hmmm...i was just reading about hfss-IE and FE-BI and ran into your post. So, all we have to do is check the "Model exterior as hfss-IE domain" and set boundary box to lambda/10 and we should have a Hybrid FEM/IE solution? Is there anything else we need to do? Also, how (...)
No worries. Yes you can use waveport in this structure with a PEC cap on top of it,since hfss does solve inside so a waveport inside the radiation box yields you an error. so put a PEC cap on top of the waveport. No i havent really worked with a CPW prior to this one.But if you have any literature pertaining to your question i should be able to h
but am doing simple rectangular wave system is 64 bit and am using that the problem? i would agree that using hfss v10 is a problem... hfss14 is now available, and MUCH better!
You want to keep effective lambda / 4 for radiation boundaries and effective lambda / 10 for PMLs. However, if you want correct far field patterns, you will need to go to hfss -> Boundaries -> Edit Global Material Properties and change the global material from air to whatever the immersed medium that the (...)
Hi, so first of all, take care of the RadiationBox dimensions...from the hfss guide we know that this should be at least at lambda/4 from the radiating surfaces..check you design to assure that. What is the frequency range ? best
in SIWave you can simulate the PKG of a chip, you can use also hfss and Q3D from Ansoft. if you go for any of these directions, you should use the Ansoft Links tool to import your bondwires/solderballs/layout/etc. For higher freq you should use hfss, if your structure is electrically short (lambda/10 rule) you can use Q3D, (...)
Hi all, I am wondering if someone could take look at my CPW hfss project and explain to/show me why it is not working. I am simply trying to simulate a high-Q, 2-lambda resonator, whose resonant frequency is 2GHz. My results do not show any well defined resonant peak or a high quality factor. I have tried everything I can think of (...)
hi friends i'm working on a slot antenna.and i wanna know how should i define the dimensions of radiation box in hfss.
For the boundary : you will define a radiation boundary with size of lambda/4 on both sides. For the excitation : you can use a waveport. Check this website: em: talk - Electromagnetics and Microwave Engineering , it has few examples in designing in hfss
HI I am trying to simulate the eigenmode of a cylinder cavity, but everytime I hit the running, the process bar just gets stuck while doing "lambda refinement" and never go forward. I attached the model (hfss-V12) here, can somebody tell me how to solve this issue? THanks.
Hi ihamieh, You cannot get the information about the actual distance covered by antenna using hfss results. Using the Friis's equation mentioned by ghb, you can calculate that. But for that you need to know the gain of the Tx antenna, power transmitted and power received and the remaining parameters. and what 'ghb' (...)
Hi, I used the online synthesizer for a 50 Ohm CPW line. I simulated that on hfss V.11. and got a 50 ohm result too. But somehow the CPW structure radiates, not sure if it was from the feeding or the structure itself. The maximum gain from the 3D polar plot was around 6 dB. The radiation box is approx lambda/3 away from the structure. I (...)
I have made s simple dipole with lumped port at center and variable air box size. The impedance changes quite a bit versus air box size. I think hfss recommends at least 1/4 lambda from antenna element. Zreal changes from 82 ohm to 95 ohm when size increases from 1/4 to 1 lambda at 1GHz. The minimum Zreal at 82 (...)
Hi guys, I'm using hfss to simulate an antenna, and I've run into an interesting problem. The antenna is surrounded by a standard airbox, lambda/8 at the longest wavelength away from the antenna, as recommended. I'm interested in simulating the effect of an infinite ground plane on the antenna, so I use a perfect E (...)
Of course each iteration uses more ram.. it is using ever more tetrahedra to mesh. Waveguide filtters are tricky, as they are large compared to lambda but there are some get-arounds: If it is a normal type of filter, these are very well understood, and there are standard formulae for calculating a starting point. They are usually (...)
i am simulating a monopole antenna lambda/4 for 435 mhz in hfss. i am getting an error that simulation of the mesh is complex and thus the simulation does not start. please suggest a way to simulate the 435 mhz lambda/4 monopole because the mesh is very large. also please suggest all the parameters affecting the radiation (...)
i mean if i have the same structure simulated using hfss and q3d what is the error between the s matrix from both ??
dont know where u can download the hfss file but for a monopole the width is less than lambda/20 and the length is supposed to be just less than lamda/4. i hope it explains your question. regards sajid mohammed.
u can use hfss to do works fine but u know with a finite ground plane your gain would be 3-dB less than what it is supposed to be and the sidelobe levels shoot up.the concept of finite ground plane is when u assign the dimensions of it less than 10*lambda.anything more than that is considered infinite ground plane. regards sajid mohammed
Hi, I'm simulating a mushroom structure in order to extract circuit equivalent parameters at 11 GHz. lambda refinement set to 0.05 ΔS=0.05 The problem is how to mesh correctly the via ?because the meshing subject is not clear at all in hfss help. Thanks
Hi, I'm working on an UWB antenna and I don't know how I fix the dimension of the radiation box?? I know (lamda / 4) but if I?m working on an UWB band from 0.3 GHZ to 4.5 GHz for example so what is the lambda to choice (corresponding to which frequency??) Thank you for your reply,
can you upload antenna's hfss file to forum? or email it to m_zw@hotmail.com i try to modified it
Hi ! I?m trying to simulate a folded slot antenna in hfss. However, I found that the Z parameters response, strongly depend on the size of the substrate in the X and Y direction. Of course I kept the thickness of the substrate constant and the air box radiation is lambda/4 high. Please, could anybody suggest me how can I (...)
hi i know the relation to find the impedance of helical antenna according to kraus is 140*C/lambda for axially fed antenna plz tell me is this true for any conductor size, any number of turns for a particular central frequency. and how to check impedance of helix of in hfss? thanks in advance
you mean hfss ha? It may also arise because of a non-smooth transition. make your contacts as smooth as possible. for example when a sphere and a large cube intersect
Has any one had a problem when using mesh settings (either manual or lowering the value of the lambda refinement of initial mesh) in computing far-fields. We have noticed that sometimes when we set these mesh properties too high, the far field calculation becomes garbage even though the S-parameters are correct. Any thoughts are appreciated.
Hi Friends, Recently I use hfss to simulate a circular patch loaded with annualr ring antenna. S parameter is ok, but the directivity is below than 1. I seed the air with lambda/10, and the boundary is lambda/4 away from the radiation element, but the result is same. Anyone can give some advice? Thanks a lot! The (...)
hfss regular array works fine with dipole array, make single dipole at origin and use the array setup, you dont need to have two or more anteenas physically just draw one and use array setup.
Hi everyone... I want to simulate phased array (2-dipoles quater lambda spaced)antenna 1: Far field pattern 2: Directivity 3: Gain...etc..... which is appropriate....MATLAB or hfss. MATLAB is not recognizing polar or polar_dB commands... it may need antenna toolbox.....I have RF toolbox... About (...)
I have an array of two dipoles spaced lambda/2 apart, and according to Balanis textbook result, I should get a different radiation pattern when the excitations are 180 degrees apart in phase. In my simulation, however, I see no difference in the pattern when I change the phase of one of the excitation. I was wondering if there was any other met
Hi, I'm starting to use hfss so I must be doing something wrong. As you may see in my file I am trying to get a planar antenna to work. However, S parameter is (in absolute value) too low, I was expecting something greater than -20dB. Please help me. The hfss extention has been changed to hfs Thanks Pedro
1. Try installing 3 GB of RAM. hfss v10 is compiled to utilize a PC with 3 GB of RAM, although there will be an upper limit. The other solution is to use a 64-bit OS such as Linux or Unix. This circumvents the entire memory addressing limitation of a 32-bit OS. 2. Radiation boundaries can be placed up to lambda/4 away from the antenna. PMLs can
hi, i have posted a tutorial on hfss so you can see it on this url good luck