# Search results

1. ### a question about Maxwell equation

please refer to the attached picture. thanks:)
2. ### How to calculate/estimate the resonate frequency in Microstrip Resonator?

Hi, If i have a microstrip line with dimension W and L, (L>W). The substrate is of height H and dielectric constatnt Er ( Hence an effective dielectric constant Eeff can be calculated). This segment of microstrip line should resonate at certain frequency right? So I have 2 questions: (1) How...
3. ### compact phase shifter at 1MHz

Hello, I am trying to build a compact phase shifter at low frequency, say 1MHz, with a phase shift of ±140~150 degree. The phase shift does not have to be tunable. Could you please show me some directions on it? Thanks a lot! p.s. i have done some literature review and found out that phase...
4. ### Measurement using UTF (Universal Test Fixture)

universal test fixture Hi there, I have fabricated stripline bandpass filter on LTCC. A pair of extra vias and pads are added to elevate the buried striline port up to the surface so that measurement can be done by UTF. The performance of the filter looks fine under HFSS simulation. However...
5. ### [Matrix Manipulation] Help plz!

Assuming $P=\left[\begin{array}{cc}A & B \\C & D\end{array}\right]$ and $Q=\left[\begin{array}{cc}D & B \\C & A\end{array}\right]$ where A, B, C, D are unknown. It's also known that $P\times M\times Q=T1$ $P\times X\times Q=T2$ where X is unknown M, T1 and T2 are known. All the...
6. ### [Modelling] Good capacitor model?

hi i am trying to find a better Metal-Insulator-Metal capacitor model. This is what I have right now: C=Er*E0*(a+f)*(b+f)/h where a, b are the width and length of the two rectangular plates; h is this distance between the two plates, (or thickness of the insulator) and f represents effective...
7. ### [Help]Solutions for Cam Nguyen's book

Could anyone please upload the solution manual to "Analysis Methods for RF,Microwave, and Millimeter-Wave Planar Transmission Line Structures" by Cam Nguyen Thank you very much!
8. ### Loss tangent DECREASES with frequency???

hi as loss tangent can be expressed as tanδ=σ/(ωε) so it decreases with frequency. but i also heard that loss tangent will increase over frequency. e.g. page 16 of Cam Nguyen's "Analysis Methods for RF, microwave, and millimetr-wave planar transmission line structures" so am I missing...
9. ### Cylindrical Coordinates

Hello, I am reading Electromagnetic Fields, 2nd Edition by Ronald K. Wangsness, and doing its exercises. I have problem solving Question 1-19, as following: Question: Given vector A= a*ρ+b*φ+c*z, where ρ, φ and z are the unit vectors of cylindrical coordinates. Find the rectangular components...
10. ### Good beginner book on EM theory

Hi I am currently researching on transmission line filter design. However, I feel quite confused when people talking about TE, TM010 modes, dispersion, skin current, even, odd mode etc. I guess that's due my lack of knowledge in EM theory. So could you please recommend me some good books on...
11. ### HFSS Eigenmode with or without big airbox

hfss eigenmode Hello I am using HFSS 10.0 to find out the resonant frequency of certain transmission line resonator in a multilayer substrate. kind of a stripline structure, i.e., the substrate's top-most and bottom-most surface are covered with good thin conductor as ground; the remaining 4...
12. ### Mechanisms of energy coupling between transmission lines?

Hello I am currently working with transmission line filter design (stripline filter, to be specific) I always see books/papers/other articles saying something like below when analyzing filters with parallel transmission lines: (1) SL1 and SL2 couple the major portion of signal energy between...