printed dipole calculator

Hello,

I am designing a half wave printed dipole antenna and I have one question: when considering the length of the dipole arms (which should be 1/4*wavelength), what wavelength should I take? Shall I use the free space wavelength - since the antenna radiates into free space - or, the effective wavelength calculated for a microstrip line.
I've read in this article that the considered wavelength is somewhere in between the 2 options. Length=19=wavelength/4 for 2.4GHz, meaning free space wavelength/4=31.25mm the relative permeativity of the dielectric is 4.6.

Thank you!

it has more loss in the substrate. permitivity is larger, so wavelength should be smaller than it is in the free space. it depends on the substrate material you use.

I'm using FR4 of 1.6mm thickness

Using an EM simulator, or a physical FR4 PCB with the dipole printed on it, just tune (short) the arms of the dipole until you get the resonance at 2.4GHz.

Not sure if this helps, but you can find the propogation delay using a transmission line calculator like mdtlc.sf.net It allows for solder mask and substrate dielectric to be included in the calculation. An improved solder mask coating drawing algorithm should be available in about 3 weeks.

thanks

thank you all