A beam steering is mainly used in the Near field communication(NFC) devices and radio communication system. Beam steering is the process of changing the direction of the main lobe of the radiation pattern which is done by switching antenna components or by changing the phase of the signal. Low loss phase shifters can be used to perform beam steering ,by which the direction of main lobe can be controlled at THZ . The switched line phase shifters are the commonly used one which is designed by using 2 transmission lines are reference line and delay line.