Patent ID: 7528675

Claim:
A broadcast receiving apparatus comprising: a board; a first broadcasting signal processing element formed on the board for outputting an unbalanced broadcasting signal; a second broadcasting signal processing element formed on the board for receiving a balanced broadcasting signal as an input; and a balance to unbalance transformer (BALUN) comprising: first and second input terminals; first and second output terminals; and a microstrip line formed on the board for transforming the unbalanced broadcasting signal output from the first broadcasting signal processing element into the balanced broadcasting signal and outputting the balanced broadcasting signal to the second broadcasting signal processing element, wherein the second input terminal is directly connected to a ground, and wherein the microstrip line comprises: a first microstrip line formed on the board and directly connected between the first input terminal and the first output terminal, wherein the unbalanced signal is transmitted from the first input terminal to the first output terminal as a first output signal; a second microstrip line formed on the board and directly connected between the second input terminal and the second output terminal, wherein the unbalanced signal is transmitted from the second input terminal to the second output terminal as a second output signal with a phase difference of approximately 180 degrees with respect to the first output signal; a third microstrip line formed on the board and directly connected between the first and second input terminals, wherein the third microstrip line is longer than the first microstrip line by approximately ¼ of an input wavelength of the unbalanced signal input through the input terminal; and a fourth microstrip line formed on the board and directly connected between the first and second output terminals, wherein the fourth microstrip line is longer than the second microstrip line by approximately ¼ of the input wavelength of the unbalanced signal input through the input terminal.