Two-port network transmission parameters?

In summary, the homework statement is trying to find the parameters for a two-port network transmission. First, they found the equivalent capacitance and inductance. Next, they did nodal equations to find the parameters for V1 and V2. Finally, they found the parameters for t11 and t12 by plugging in the values for I1 and V1 into the equations. They also found the parameters for t21 and t22 by plugging in the values for I2 and V2 into the equations. However, the opposite was true for t11 and t12. Lastly, they don't know how to get the rest of the matrix elements for the admittance Y(s).
  • #1
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two-port network transmission parameters??

Homework Statement


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Homework Equations


t[A B]=[t11 t12]
[C D]=[t21 t22]

The Attempt at a Solution


so, first thing i did was find the equivalent capacitance/inductance. C(eq)=-j0.5 and L(eq)=j0.5.
using these values as I was confused by parametric equations in general i decided to do nodal equations. using V1 as the node left of resistance R, V2 as the one right of it. since in my book, they do nodal equations to check the values of y-paramter matrices.

V1 equation: (1+j2)V1+(-1)V2=0
V2 equation: (-1)V1+(1-j2)V2=0

since the t equation (choice A) had different sign values than the nodal matrix, i guessed this was wrong. choice B also looked wrong because it only had the C(eq) value, so I chose choice D because that looked similar to (1-j2)V2 in the equation for V2. i obviously know i am doing this wrong.EDIT: looking over my notes i think this is a 't-parameter' problem. According to my teacher, the T-parameter matrices for each of the following:
Z(ohm) [T] matrix:
Code:
[1  z]
[0  1]

Y(s) [T] matrix:
Code:
[1  0]
[Y  1]

where Z and Y are the values. i am assuming Z if for resistor or any real value, Y is for imaginary part and I think the admittance. i still don't know why the matrices are structured like this, though. but if i assume this is correct, choices B, C, and D are all wrong because they don't follow the format. that leaves only A.
 
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  • #2
question 1: it says "C = 10 mF". Do they really mean 10 mF or do they mean 10 uF? It is most uncommon to express capacitance in millifarads.

Now: you need to know the two equations for the ABCD parameters in terms of i1, i2, V1 and V2 for each section t, t1 and t2. What are they?

OR: find the Z, Y or other parameters for each section and then translate to ABCD parameters.
 
  • #3
i think i know how my teacher got t12. suppose R=3ohm, t12=V1/-I2, and -I2 is just 1V/3ohm, then 1V/-I2 would just flip it and give you the value of resistance. another way is since t12 is in units of ohms, it would just be resistance value. t21 is in units of (S) so it would just be admittance for Y(s). and i do have the equations for V1/I1/V2/I2 but i think my main problem is i don't know what values to use. it is also the only other way my book lists to find the other matrix elements.
V1=I1+0I2
V2=1I1+0I2

solve V2 equation for I1:
1I1=V2-0(I2)
so t21 and t22 should be 1 and 0. but the opposite is true.

plug in I1 into V1 equation:
V1=1(V2)+1(I2)
which gives t11=1 and t12=R..?

also, I still don't understand how to get the rest of the matrix elements for the admittance Y(s). I know t21 is in units of (S), so it should be Y, but that's as far as I get.
 
  • #4
You already have the Y parameters. As rude man suggested, use the transformation from Y to t parameters.

You can find a table of transformations (the t parameters are also known as a parameters) here:

http://en.wikipedia.org/wiki/Two-port_network

near the bottom of the page.
 
  • #5


A two-port network is a circuit with two input and two output ports. The transmission parameters, also known as ABCD parameters, are used to describe the behavior of a two-port network. These parameters are represented by a 2x2 matrix and are used to determine the voltage and current at the input and output ports of the network.

The transmission parameters are defined as follows:

t[A B]=[t11 t12]
[C D]=[t21 t22]

where t11 and t22 represent the input and output voltage ratios, and t12 and t21 represent the forward and reverse voltage gains. These parameters are measured in terms of impedance or admittance, depending on the type of network being analyzed.

In order to solve for the transmission parameters, you can use nodal analysis or any other appropriate method to determine the voltage and current at the input and output ports. Once these values are known, you can then plug them into the equations and solve for the transmission parameters.

In summary, two-port network transmission parameters are used to describe the behavior of a two-port network and are represented by a 2x2 matrix. These parameters can be solved for using various methods, such as nodal analysis, and are measured in terms of impedance or admittance.
 

1. What are two-port network transmission parameters?

Two-port network transmission parameters are a set of four parameters that are used to describe the relationship between the input and output voltages and currents in a two-port network. These parameters are commonly used in the analysis and design of electronic circuits and systems.

2. What are the four parameters included in two-port network transmission parameters?

The four parameters included in two-port network transmission parameters are:

  • Forward voltage transfer gain (Av): This parameter describes the ratio of output voltage to input voltage when the output port is open.
  • Reverse voltage transfer gain (Bv): This parameter describes the ratio of output voltage to input voltage when the input port is shorted.
  • Forward current transfer gain (Ai): This parameter describes the ratio of output current to input current when the output port is open.
  • Reverse current transfer gain (Bi): This parameter describes the ratio of output current to input current when the input port is shorted.

3. What is the significance of two-port network transmission parameters?

Two-port network transmission parameters are significant because they provide a convenient and concise way to characterize the behavior of a two-port network. They can be used to analyze and design complex electronic circuits and systems, and can also be used to compare different two-port networks.

4. What is the difference between two-port network transmission parameters and S-parameters?

Two-port network transmission parameters and S-parameters are both used to describe the behavior of two-port networks, but they are calculated and used in different ways. While two-port network transmission parameters are based on voltage and current ratios, S-parameters are based on voltage and current reflections at the ports of the network. S-parameters are also commonly used in high-frequency applications, while two-port network transmission parameters are more commonly used in low-frequency applications.

5. How are two-port network transmission parameters measured?

Two-port network transmission parameters can be measured using a network analyzer, which is a specialized instrument that can measure the input and output signals of a two-port network. The network analyzer can then calculate the four transmission parameters based on the measured signals. Alternatively, the parameters can also be calculated using the circuit's physical components and mathematical equations.

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