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Knowledge Base

Returns the expansion coefficients between the fields recorded at two arbitrary DFT monitors or saved in two d-cards. The coefficients are defined according to:



For more detail on how to use this command, definitions on the parameters and how to interpret the results, please see Using Mode Expansion Monitors. Note that N is the power of the waveguide mode. conj(N) is equal to N if this is a real number. For the unconjugated coefficients, see expand2.


Supported Product: FDTD, MODE





outputs the expansion coefficients between the fields of two monitors (or d-cards)

'monitor1': name of the monitor (or d-card) containing the fields E1 and H1 of which the expansion is performed

'monitor_ref': name of the reference monitor (or d-card) containing E2 and H2

x,y,z: spatial displacement of the fields from monitor1 with respect to those from monitor_ref



The following script expands the fields from monitor "R" onto the reference monitor "R_ref":

M = expand('a','b',0,0,0);

f = getdata('R','f');

a = pinch(M,1,1);

b = pinch(M,1,2);

n = pinch(M,1,3);

p = pinch(M,1,4);

S11 = b;


See Also

Adding Objects, Using Mode Expansion Monitors, setexpansion, removeexpansion, expand2

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