Thanks for the reply sv1437,
The design of the antenna is being done by the software CST Microwave Studion, and to achieve a phase difference of 180 degrees, I am using a difference of lamda/2 in the microstrip line. However, to make it a completely lossless line, I need to design the T junctuin in such a way that no signal gets reflected and both the channels receives the same amount of signal.
To do that, I need an equation to compute the width of the T junction line. If you could help me with that, I would really be very grateful to you.
Thanks.