How to design an antenna to operate at 3 and 5 GHz?

[cehan]

i am working on microstrip patch antenna...i gonna design antenna to operate at 3 and 5 GHz...but my design gives just 2.3 and 4.5....i want to shift or modify s11 to the desired values 3 and 5 GHz..
is there any suggestion to solve such case....
here attachment for s11 graph on hfss 15.

 

[Umar608]

If you want to get two resonance with patch antenna, the best way would be to first design a patch resonating at 3 GHz and then add a slot to make it dual band. The dimensions of the slot can be so adjusted that the antenna has a second resonance at 5 GHz

 

[cehan]

thnx a lot Umar608 the substrate thickness and material type were the most important parameters.

 

[Li-iOnes]

you need to reduce dimension patch antenna.

 

[ferdows]

it s impossible to achieve this BW at this frequency
try other antenna

 

[hof]

Try smaller patch dimensions.