How to load a quarter wavelength monopole
How to load a quarter wavelength monopole
(OP)
Hi all,
I am currently working on a project and would require me to reduce the efficiency of a 1GHz quarter wavelength monopole antenna. Through calculations, in order to reduce the efficiency to 50% & 75&, I would need to load a 18 and 10 ohms resistor respectively to the feeding pin of the antenna.
Does anybody know what type of resistors to use and also, how should I connect the resistor to the antenna so that the antenna can stand vertically straight on a SMA connector, which is attached to a ground plate.
Thank you.





RE: How to load a quarter wavelength monopole
If it needs to be just with the antenna, then can you use a poor material for the element ? Given the skin depth at 1GHz, it should be a simple matter to drop a few dB from theoretical perfection.
RE: How to load a quarter wavelength monopole
Please tell us some more about why you are trying to reduce the efficiency. The most obvious way is reducing the length of the antenna!
RE: How to load a quarter wavelength monopole
If you are going to build the attenuator yourself and assuming it is low power, use preferrably surface mount resistors, or of otherwise metal film resistors with VERY SHORT leads.
RE: How to load a quarter wavelength monopole
visit:
http://www.cumingmw.com/micro_rf.html