The 3port device as shown below is connected to a lossless t

The 3-port device as shown below is connected to a lossless transmission line with characteristic impedance Z_0 = 50 Ohm and electrical length beta1 - pi/8. The transmission line is terminated with a Short - Circuit. If port 3 is also connected to a Short - Circuit, determine the S_11 of the combined network.

S11 = I2/ V1

= 50 Cos(22.5) /0.5