微波EDA网,见证研发工程师的成长!
首页 > 研发问答 > 微波和射频技术 > 电磁仿真讨论 > How to chacterize matching?

How to chacterize matching?

时间:03-22 整理:3721RD 点击:
I wonder what is the relavant quantity when characterizing the matching properties of an antenna? Isn't it the magnitude of S11? or am I mistaken?

I think You are correct !

Normally matching refers to minimizing the reflection co-efficient. In case of 1 port networks S11=-20log(Γ) where Γ is the reflection co-efficient.

so I am correct?

For antennas, by the word "matching" , matching of the antenna to the power source that drives the antenna is meant. For instance you have a halfwave dipole antenna which has a radiation resistance of 73 ohms. The coaxial cable which delivers power to this antenna is a typical 50 ohms coaxial. In this case you have to insert a matching network between the antenna and the coaxial transmission line. this is called matching. the S11 parameter of this network actually defines how good the matching is. In my opinion, only antenna itself does not mean anything to matching.

For arrays of antennas matching is more troublesome because each antenna in the array will most probably have different rad. resistances. in such a case mostly microstrip stripline feeding method is used. In the first example, even a simpled lumped element network could be sufficient.

Irfan Hocam, why not have a look at the Antenna Theory book by C.A. Balanis section 9.8 "Matching Techniques"? It would be useful.

Z. K.



Well, I am not trying to match an antenna to anything. I just need a relavant quantity that defines the matching. I am not an antenna expert, and the antennas are not my research field. But, in my opinion, if I were to define matching the relavant quantity would be S11. It is as simple as that. The lines could be matched somehow. But the overall antenna could not be matched to the free space for instance.

tanisiyoruz sanirim

Copyright © 2017-2020 微波EDA网 版权所有

网站地图

Top