microstrip line

i am designing a patch antenna i have calculated its width and its length also have the inset position i have to feed the patch by a mircostrip line of 50 ohms how can determine the width of the microstrip line are there any rules that i need to fallow ?

http://chemandy.com/calculators/micr...calculator.htm

thankyou :)

the above link no longer exists so u can use the folling tool i found online

It is OK

yes i used it to design a microstrip line for a patch antenna the resuts were correct