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1. slow-wave and fast-wave

Oh yes that's my terrible mistake. Thanks for correction. Slow-wave (guided-wave): vp<c or β>ko Fast-wave (leaky-wave): vp>c or β<ko

In the retrieval methods there are ususally ± roots and multiple branches. You should select the ones which are not violating the fundamental laws of physics. Imaginary n must be positive all the time. For example looking at your graph, I can say that you should select -n from 0 to 8.7GHz, +n...
3. slow-wave factor in IE3D

Slow-wave factor is defined as c/Vp or β/ko. ko=2πf/c and β is the imaginary part of the propagation constant (γ=α+jβ). You can calculate it from ABCD matrix or from S-parameters...
4. slow-wave and fast-wave

For waves to be fast, their group velocity should be greater than speed of light c. If the group velocity is less than speed of light, it is called slow-wave. By playing with the refractive index of a medium we can make the wave slow, fast or ordinary.
5. help in drawing log spiral antenna

2d spiral dxf Once imported, you cannot change any parameter in the layout. You can modify the objects by adding or substracting other objects but you cannot change the spiral parameters.
6. wave propagation in di-electric medium

See the refraction chapter at any electromagnetics book...
7. help in drawing log spiral antenna

log spiral Above code gives you a 1D spiral curve. However by defining the width you can make it a 2D planar spiral strip. I'm not an expert on AutoCAD lisp routines so I don't know. I always do it manually...
8. help in drawing log spiral antenna

draw spiral autocad The following routine will draw you a 100-segment Archimedean spiral given by the polar equation r=A*ang^(1/nn) where the polar angle "ang" sweeps 0 rad to 3*pi rad. When you draw the spiral simply select the curve, use "_pedit" command and then "w" to assign a track...
9. permittivity and permeability using HFSS

xudong chen metamaterial matlab code I'm working on the similar problem and it is a very tricky issue. You have to be very careful since each method has some weakness due to certain assumptions and approximations. Structure geometry and symmetry properties have important influence on the...
10. S parameters of an FSS in HFSS

hfss fss phase Check this out for normal incidence.
11. what types of antennas work at freq. as high as 100GHz?

Below, they use a Vivaldi antenna at 60 GHz. There are people using simple bond wire antennas, too. h**p//www.ihp-ffo.de/fileadmin/ihp-template/departments/circuit-design/news/WWRF16_SUN.pdf
12. What kind of feedline can this be called ?

Perhaps you can call it "EBG structure based on perforated microstrip line" or "periodically loaded microstrip line". Make sure that the structure has the stopband property by simulating a portion of the microstrip line itself without the antennas. The distance of the structure to the antenna...
13. Where exactly are EBG structures inserted ?

Re: EBG structures It depends what kind of structure you have and what the application is. There are several types of EBG structures. The first designs consist of holes drilled in the substrate. A few other structures have holes etched in the ground plane only etc. In general, EBG strutures...
14. How to use the LISP routine in AUTOcad to create sinuous antenna arms?

Re: AUTOcad help needed! Firts of all equation based curve came with HFSS v.10. If you are using an older version, you cannot find it. Equation based curve is very easy to use. All you need to do is to transform your original equation into a pair of parametric equations of a free variable 't'.
15. wireless channels in matlab

hi guys, I was wondering how to realize random wireless channel in matlab. Any idea? Thanks.
16. What is Zero Forcing (ZF) in Wireless Communications?

zero forcing Hi Arif, ZF means when u have mutiple users and ur transmission is intended for one particular user and zero transmission (ideally) for others. But in practice there is interference for other users when u considering BC. I hopw this will help u. BR, Oz.
17. Understanding Maxwell Equation

Hi Arif In the static case none of the quantities appearing in maxwell's equations are a function of time and they reduce to following Δ•D=ρ ΔxE=0 Δ•B=0 ΔxH=0 As you see the electric and magnetic fields are no longer interconnected and four equations seperate into two uncoupled pairs.
18. What is the x-layer design in wireless networks?

Re: x-layer ? Thanks mate!
19. What is the x-layer design in wireless networks?

Hi guys, What is x-layer design in wireless networks? BR, Oz
20. How to use the LISP routine in AUTOcad to create sinuous antenna arms?

Re: AUTOcad help needed! HFSS v10 has an equation based curve function. You can define your parametric equations there and draw any curve. Then you can draw another line/sheet and sweep along the path...