hello;
im going to design a printed antenna withcoaxial feeding resonants at 3 and 5.5 GHz at the same time.
i modelled this antenna with cst and hfss respectively. simulation results are fitting. so i fabricate this antenna and get the measurement results. but there are differences between simulation and measurement. i dont know what is wrong?
can you help me
Looks like a considerable difference in substrate Er or another parameter that influences the effective wavelength.
Also the impedance matching is apparently affected.
the manufacturing seems ok, but i dont know why are the results so different.
as you see, i modelled coax in simulation and get good results. in practical can i get these results by coax or must i use a balun structure? can you say anything about this?
thanks for the help
Do you have photos of the manufactored sample? Especially detailed view of the feeding connections. This might be helpful to analyse what is going on here.