Dicussing about surface current
This topic related in disccussing surface current in designing antenna.
When you disgn some antenna, on of experience is how to understanding surface current's behaviuos to make adjustment in your desgin.
You can base on some equation on some book to choose the dimension ( increase the lenght and the frequency down etc..., but the problem is that you can not calculate like the way the books calculate. It is so complex and take time, and if you want to change some parameter, you must recalculate again. that is a burden
It did not supply you the quick way to design antenna. The simulate program can do it for you. And the probelm is that equation is only written for the known antenna, simple antenna. The more complex antenna, the new antenna we can not use this way.
One exprerience guy tell me that we can base on surface curerrent to adjust, for example when you see in the part of antenna that the surface current is hight , you change something in this part and then the other charactoristcs of your antena will change much, if the surface current in this part is very small, when you change this part the other charactoristcs of your antena will change a little. That one of example in designing antenna by experience.
Another example is the the flow direction of surface current. When you want to design two or three band antenna, you must know how surface current flow in your antenna. In this frequency the surface current will flow by this part, but other frequency the surrface current willl flow in other part , so you can change each part cho change behaviuos of antenna in each frequency independently. So why the surface current flow in this part in this frequency, and why other part in other frequency?
But a little or only a few paper, book writing about this problem. It seems very hard to understand quickly by reading books adn paper only. So I ask some helps from experience guys.
Tha why I post this topic here to discuss with some man who have experirence in designing antenna by using simulation program. It also will help beginner to quickly be familiar with designing antenna.
Thank you for redeading this topic
its related to the electromagnetic force that induces some current on the surface and cause heat and loss in antennas
Do you guy know any good paper and book analysing this problem
Hello
Yes,"Advanced Electromagnetic" By: Harington very useful for this subject.
Thank you. I will read it.
Added after 26 minutes:
Sorry. I found only the book name "Time Harmonic Electromagnetic Fields" of Harington, not the book " Advanced Electromagnetic". Is that the book you mention
Is these related to Skin Depth?
Check for the following book u may find your doubt.
High-Speed Signal Propagation: Advanced Black Magic
By Howard Johnson, Martin Graham
Publisher : Prentice Hall PTR
Pub Date : February 24, 2003
ISBN : 0-13-084408-X
Pages : 800