Questions tagged [scattering]
10 questions
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How is Wilkinson power divider lossy?
In an ideal Wilkinson power divider(because in practical there will always be resistive loss), the scattering parameters, or S matrix is given as:
From the condition that checks if network is loss-less or not which is:
Say s-parameters matrix is…
Prasanjit Rath
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Direct ABCD matrix calculation from incident and reflected currents and voltages (i.e. obtained by 2 port FDTD simulation results)
Usual method for transmission (ABCD) matrix construction, from 2 ports EM simulation results, is to first calculate S parameters for each port i.e.:
s11 = port{1}.Vref / port{1}.Vinc;
s12 = port{1}.Vref / port{2}.Vinc;
s21 = port{2}.Vref /…
Danko Dnevic
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Antenna impedance (one port network), represented as ABCD (transfer) matrix?
I guess that ABCD matrices are not intended for one port, but, in this case, for the purpose of cascading two networks, 2 port (impedance transformer) and 1 port (antenna), by ABCD matrix multiplication, I want to represent antenna impedances - as…
Danko Dnevic
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Calculation of scattering parameter
I am not able to calculate the scattering matrix of a pi-circuit although I have calculated its Y matrix. The needed scattering matrix is referred to 50Ω.
Could someone help me on calculating the scattering matrix?
I tried to deduct the S50 matrix…
tonyjk
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Do scattering parameters change with velocity?
I'm using the HFSS SBR+ solution type. I have one PEC sphere and two parametric beam antennas. I am trying to find out how much S parameters change with the Doppler effect.
Configuration:
Range Resolution: 1 m
Range Period: 200 m
Velocity…
merovingian
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Avoiding thermal noise to enter low temperature while not using dissipative element
Let's assume that we want to interact with a circuit at very low temperature \$T2\$ to avoid any source of noise. The voltage interacting with this circuit must have a specific target value \$V0\$. Imagine for instance a waveguide terminated by an…
StarBucK
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Scattering matrix in microwave amplifier
What exactly is the scattering matrix in a microwave amplifier. I tried to deduce from lectures what it is used for in a microwave amplifier, but all I found were the formulas corresponding to the calculation of such matrices. Does anyone have any…
MagicMan
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Is RF propagation path loss symmetrical and independent of clutter location?
Scenario: Consider two measurement points, point one is about 3m above ground level within a cluster of buildings (such as within an office park), and point two is about 1km away with an elevation angle of 30 degrees from the first point.
With ideal…
bud bert
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power waves and scattering matrix
I have some doubts about the concept of power waves used in the description of the scattering matrix of an N-port component. In particular, I was wondering what is the most general and correct definition of incident and reflected power wave . In…
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Measurement of s11 with reduced power on NanoVNA
I am developing a 10.7 MHz IF amplifier for a radio receiver. In order to match the input to the output of the driving mixer stage (330 ohm) I need to measure the input impedance.
I did the measurement with a NanoVNA (I don't have access to a…
Bart
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