folded monopole antenna

hi,i am currently working on the mobile phone antenna in my university research.i have some question while in my progress. Below is my questions,
1.how do you estimate the geometry of the built-in folded monopole antenna?
2.how to fold the antenna.it is based on what teory?
3.how do you estimate the length of every side of the folded monopole antenna?Is there any formula or teory that can recommand to me?
4.how to choose the thickness of the copper plate that used to built the antenna and ground plate?

thanks for your help

read this paper

and http://www.w8ji.com/radiation_resistance.htm

Hi

I did a folded monopole a long time ago and I will try to see if I can answer your questions.

Feel free to correct me if I am wrong. Ans to your question are as follow

2) As its name suggest, it is a folded version of the folded dipole antenna.

1) The actual folded monopole length is approximately 1/2 wavelength.

3) THe theory are the same as conventional monopole and dipole.

4) The thickness of the wire used to built the folded monopole will have an impact on its BW. Too difficult to explain in depth here. Also for the monopole antenna to work properly, you will need a good size gnd plane

Hope i ans your question

Hi:

I think one more reason people use folded dipole is for matching. A typical dipole antenna with normal radius has a Z = R + j X = 75 ohms at the resoance defined as jX = 0. A folded dipole's impedance will be about 4 times as big. It is close to 300 ohms and that is why many old TV sets used folded dipoles with 300 ohm parallel line.

Best regards,