How to Calculate the Coupled Transfer Function of Two RC-Filters?

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To calculate the coupled transfer function of two RC filters, the individual transfer functions H_1(ω) and H_2(ω) can be derived using the impedance model. When coupling the output Uo(1) of the first filter to the input Ui(2) of the second, the resulting transfer function is not simply the product of the two. A more efficient method involves using the node voltage method to analyze the connected nodes Uo1 and Uo2. While there may be tricks to simplify the calculations, the discussion suggests that the node voltage approach is a reliable method. The importance of clear communication and updates in forum discussions is also highlighted.
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Suppose you have two RC-filters as shown below. Ignore the #'s, they are for spacing purposes.

o---R1--------o
# # # # # | #
Ui(1) # # C1 # Uo(1)
# # # # # | #
o--------------o

o---R2--------o
# # # # # | #
Ui(2) # # C2 # Uo(2)
# # # # # | #
o--------------o

Calculating the transfer functions H_1(\omega), H_2(\omega) (H(\omega)=u_o/u_i) using the impedance model is simple.
But what if you couple the two? By coupling the output Uo(1) of the first at the input Ui(2) of the second. Is there an easy way to calculate the resulting transfer function? It's not just the product of the two and my calculation is big and ugly. I know there is a trick or method to do it easily, by using some sort of substitution or something? Can anyone enlighten me?
 
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i'm assuming that your new output is the connected nodes Uo1 and Uo2. in that case i would use the node voltage method for finding the transfer function. concerning a faster way i don't know if there is one.
 
oh wow i just noticed you post is two years old! haha. you've probably figured it out already.
 
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