Regarding array antennas

Hi all,
I was trying to simulate an array antenna for which i started with the simulation of individual patches.when i simualted it individually it was resonating at a particular frequency in HFSS.I designed one power divider for array antenna which was also resonating at same frequency.This was done in IE3D.But when i combined the patches and the power divider to form an array,the resonant frequency shifted to a lower frequency .can anybody please explain me why this is happening.I'm a beginner in EM Design.
Thanks,
Sumy

Hi, Sumy: How much shift the resonance frequency is? If the shift is small, it is normal. Just like you connect a feed line to a patch antenna, if the feed line slightly off 50-ohms or the ohms you want to normalize, the resonant frequency may shift slightly and the matching may differ slightly. This is normal.

The impedance matching is a problem for it .


Sometimes we may use indutor and capacitor to match impedance.

Hi,
Thanx a lot for your replies.Jian,the shift is small only.let me try for a better match of the feed line.
Thanx,
Sumy