Parameters S12 Reverse transmission coefficient
As far as I understand she somehow does the signal isolation.
Please I need help
S12 has no dependency on antenna or other RF devices.S-parameters are definitions that relate interrelation of the Ports of a system either antenna or amplifier..
Can you post a sketch what you mean by ?
Yes, that is true, but I used this as an example to simplify my doubt is related to microwaves. Here is the outline give example.
"Quadripole" means 2-Ports right ? So, since the antenna has one port only, there won't be S12 or S21 etc.It will have S11 only and the quality of the antenna is defined S11 only by s-parameters.
If S11 is low as desired threshold, the antenna impedance is close to wanted. Antennas are checked also by EM Radiation Pattern , take it into account..
Maybe he talks about dual polarization antenna. Circular polarisation created by a power splitter with 90° phase delay.
S12 - Reverse Transmission (leakage or isolation or Insertion Loss....
I am referring to this item I did not understand the theoretical part and the practical part regarding the quadripole.
I can understand the parameter s11 on reflection coefficient and how it is calculated and its practice.
S12. I understood practically nothing.
Independent of the three figures and antennas that was put as an example
Imagine an amplifier..It has one input and one output port right ? If you apply a signal to input port, you achieve amplified signal at the output.
But if you apply a signal to output port, you cannot obtain even applied signal level, even-more the signal will be attenuated.
Same analogy.. S12 is a Reverse Transmission Coefficient.A signal is applied to Port2 and someone observe the signal at Port1..