help with ANN

[rohit@faulty.che.utexas.edu]

I am trying to design an ANN to model a function which
takes a step as an input and shifts the step in time and
changes the amplitude of the step . I am using backward
propogation with sigmoid functions for the nodes in the hidden layers, can anyo
ne  make any suggestions.
I had posted this question on the ai.neural.nets and
a couple of people said that they had done it but nobody
could tell me how they did it i.e  architecture of the net
waht inputs etc...
I would appreciate it if somone would make some concrete
suggestions.
rohit at faulty.che.utexas.edu