! PCB Planner synthetic differential-channel demonstration. Not measured hardware.
! Port pairs: input (1+,2-), output (3+,4-); paths 1->3 and 2->4.
! Transmission magnitudes 0.8 and 0.6, each with 100 ps delay.
! Reflection magnitude 0.1, phase 0; cross-path terms zero.
! Expected |SDD21|=0.7, |SCD21|=0.1, |SDD11|=0.1; group delay 100 ps.
! Touchstone 1.x, four-port full matrix in row order S11 S12 S13 S14, etc.
# MHz S MA R 50
10 0.1 0 0 0 0.8 -0.36 0 0
   0 0 0.1 0 0 0 0.6 -0.36
   0.8 -0.36 0 0 0.1 0 0 0
   0 0 0.6 -0.36 0 0 0.1 0
100 0.1 0 0 0 0.8 -3.6 0 0
    0 0 0.1 0 0 0 0.6 -3.6
    0.8 -3.6 0 0 0.1 0 0 0
    0 0 0.6 -3.6 0 0 0.1 0
500 0.1 0 0 0 0.8 -18 0 0
    0 0 0.1 0 0 0 0.6 -18
    0.8 -18 0 0 0.1 0 0 0
    0 0 0.6 -18 0 0 0.1 0
1000 0.1 0 0 0 0.8 -36 0 0
     0 0 0.1 0 0 0 0.6 -36
     0.8 -36 0 0 0.1 0 0 0
     0 0 0.6 -36 0 0 0.1 0
2000 0.1 0 0 0 0.8 -72 0 0
     0 0 0.1 0 0 0 0.6 -72
     0.8 -72 0 0 0.1 0 0 0
     0 0 0.6 -72 0 0 0.1 0
3000 0.1 0 0 0 0.8 -108 0 0
     0 0 0.1 0 0 0 0.6 -108
     0.8 -108 0 0 0.1 0 0 0
     0 0 0.6 -108 0 0 0.1 0
4000 0.1 0 0 0 0.8 -144 0 0
     0 0 0.1 0 0 0 0.6 -144
     0.8 -144 0 0 0.1 0 0 0
     0 0 0.6 -144 0 0 0.1 0