Helps hfss

Hi,

I'm working on an UWB antenna and I don't know how I fix the dimension of the radiation box? I know (lamda / 4) but if I?m working on an UWB band from 0.3 GHZ to 4.5 GHz for example so what is the lambda to choice (corresponding to which frequency?)

Thank you for your reply,

what is your operating frequency ?
this operating frequency will provide you the lambda value.

Thank you for your reply,

I don't understand I?m working on 0.3 GHz to 4.5 GHZ and I want an UWB comportment so my antenna must operate at least from 400 MHz to 4 GHz, I don?t understand what you mean by operate frequency? I haven?t only one resonant frequency but a wide band of frequency.
I will choice the central frequency for example?

Have good day,

you should use maximum Lambda/4 distance and not important if it was more than it.
for your application the 0.3GHZ has max Lambda.