Patent ID: 6611235
Filing Date: 2003-08-26
Classification: H01Q

Abstract:
An antenna coupling device (14) for coupling radio frequency signals from a communication device (10) having an internal first antenna, the communication device (10) operable in n frequency bands, where n>1 and n is an integer, wherein said antenna coupling device (14) comprises a port (16) connected/connectable to a transmission line (18), characterized in that a conducting surface of said antenna coupling device (14) has a geometric shape in the form of a tree structure (20) connected to said port (16), wherein said tree structure (20) comprises a number, m, of branches, where m&gE;n, wherein said tree structure (20) comprises at least one branch bix for each frequency band i of said communication device (10), wherein i is an integer and 1&lE;i&lE;n, and x is an integer and 1&lE;x&lE;k(i), and the total number, m, of branches satisfy the following expression &Sum;i=1n&it;k&af;(i)=mwherein k(i) is a function of i, which only can obtain an integer value and is the total number of branches for a frequency band i.