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impedance of coupled transmission lines on PCB can't match

Question asked by 摆渡今生 on Mar 20, 2014
Latest reply on Mar 24, 2014 by 摆渡今生
hello everyone! thank you for your visit.  
I have been simulating coupled transmission lines for several days,i don't know the way to simulate it directly.i simulate the four ports single-ended S-parameters first and then use some equations to turn these data into mixed mode such as Sdd11.i have several problems. 
problem 1:is there a direct way to simulate S-parameter of  diff_pair signals through coupled transmission lines?
problem 2:when i use the ideal tclin,the results is much better than pclin2, i am  wondering that the impedance doesn't match,have you ever use the linecal to calculate the impedance of PCB coupled lines?could you tell me how to calculate the impedance? 
i'm a new one to use ads,and i think the question is a little bit low-level.thank you very much for your answer.and i attach the schematic and data display window.  

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