antenna impedance measurement

hi

I was calculating the series impedance of an loop antenna and i want to know how to convert it to parallel impedance.

I did it by multiplying series resistance with Q^2 (Q is the quality factor) but i get an absurd value of about 50kOhms. for a small rectangular loop antenna of 21.5x23.5 mm antenna with a thickness of 1.5mm. Can anybody check with the values and tell me if the resistance i get is correct. I need to implement it on a PCB board for my project..

Why do you think that 50 k is so high?
If you have high Q resonator, it's parallel equivalent circuit is with an high value resistor.

What is resonant freq?

Mazz

I want it to match to a 2K-4K line.

The freq of operation is 434 MHz.

I dont want to add another matching network as it will increase the losses .

Hello,

I wonder if the 50k value was obtained with EM simulation, reflecting also radiated energy? If so, it would indicate very poor antenna properties. TI/Chipcon has published interesting application nore regarding 433 MHz antenna.

http://focus.ti.com/lit/an/swra088/swra088.pdf

Regards,
Frank