hi all
i have a question about Wavelength in the cellular world.

it is known that we can calaulate the Wavelength from this formula :
Wavelength = c / f .
so for example , if we use this frequency of 2.1 GHz
we get a Wavelength of : 14.285 centimeter.

so i'm asking if it is necessary that the antenna inside the phone must be
in the same length of the wavelength ? because when i open the phone i see that the antenna is very small and even if its folded it's still smaller than the wavelength .
it's maby possible with the use of some kind of circuit or a match circuit ? , or it is not necessary to be in same length ?


thanks !

 

U are forgetting the GSM transmitter frequency..!

Google GSM frequencies.

 

explain pls.

 

The classic lengths for antennas are λ/2 & λ/4,so,no,they don't have to be a full wavelength.

You can use considerably smaller lengths by means of various forms of "matching" networks.

These don't work as well as a properly designed λ/2 or λ/4,but are mandated by the small size required by marketing.

 

thanks vk6zgo !
it was very helpfull