A transmission line may refer to a cable or assembly that is designed to carry radio frequencies and must consider the wave nature of the signal. Coaxial cable is an example of a transmission line. It may also refer to high-voltage power transmission lines, used to transfer power from generating ...

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722 views

How to calculate return loss of the cascaded system?

If system 1 has 10 dB return loss and system 2 has 20 dB return loss then what is the overall return loss of cascaded system of 1&2 ?
3
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4answers
249 views

Why is stepping up voltage during transmission considers I^2*R but not V^2/R?

During the transmission, the generated electric power is delivered after stepping up to hundreds of thousands or even more voltages by transformers. In that case since P = I*V, increasing V reduces I ...
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1answer
37 views

Reflections on a differential transmission line

I understand why reflections occur when there is an impedance mismatch on a single-wire transmission line. However, when we introduce a differential line, I am having trouble picturing what would ...
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2answers
40 views

What is the Kuroda method for transmission lines and why is it usefull? [closed]

I recentrly heard about the Kuroda method (when speaking about transmission lines) but didn't understand what it really is and why it might be usefull. Could someone give a brief explanation? why ...
0
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0answers
12 views

Distributed and lumped line parameters model

When modeling HVDC cable in an MTDC when using lumped line parmeters model it is working ok but in case of fault there are very high frequencies in the faulted section. However, reducing the line ...
0
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1answer
72 views

Resistance of twin core wire

I'm trying to do a problem for revision and I'm running into problems calculating the resistance of this circuit used to approximate a twin-core wire. It's used later in the question with the middle ...
2
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0answers
59 views

How to calculate the earth fault current in a transmission system with no ground wire?

Background information, and my thought on the matter are provided in the end of the question. I need to calculate the fault current in case a fault occur for instance 10 km away from a transformer ...
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0answers
25 views

How many measurements does a typical phasor meqasurement unit (PMU) capture?

How many phasor measurements (voltage amplitude and phase angle) does a typical PMU capture from 1) transmission and 2) distribution lines? is it one, three, or more? Does this depend on the topology ...
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1answer
40 views

transmission line theory, complex conjugate matching

Referring to the below output matching network of an amplifier ,in which gamma_out is chosen as the complex conjugate of gamma_l (in the figure Γ and Γ*) in order to achieve maximum power transfer ...
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0answers
26 views

Phase Velocity in PCB Edge Coupled Microstrip

I would like to calculate the phase velocity (\$v_p\$) in an edge coupled (differential) microstrip such as the below. It's possible to calculate \$v_p\$ for an embedded microstrip with the ...
0
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0answers
14 views

How many measurement samples does a typical phasor measurement unit (PMU) transmit in each communication session?

Given a smart grid network, how many measurement samples (voltage and phase angles) does a typical PMU capture from a transmission line? I know that in each communication session, a PMU transmits ...
1
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2answers
66 views

voltages in transmission lines

I'm taking an EE course where we have been studying transmission lines, among other things. I know that when I am driving an unmatched load, there will be a reflected wave. My question is where ...
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1answer
35 views

Input power with PF, impedance on transmission line and transformer

I've just had and exam (Renewable Energy) and we had a problem that I'm not sure if is correct. The answers should be simple as we haven't studied tranmission lines at all. Okay, here we go. We have ...
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1answer
39 views

Using Pulse W3006 Dualband Wifi Antenna with a CPW-G Trace and Single RF_Out on MC

Pulse W3006 Chip Antenna Being Used We are designing a custom PCB which uses a micro-controller with a single RF-out capable of doing 2.4G/5G/Bluetooth. This questions has 3 parts: Using the Chip ...
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1answer
39 views

Behaviour of reflections along transmission lines

I have another question about transmission line behaviour. People always tell (at least I read it multiple times in various articles while googling) that when one is measuring the voltage along a TL (...
4
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1answer
55 views

ECL output termination

This is a rookie question, but I'm quite confused about the ECL termination used on the ADCMP565 evaluation board First, in the IC datasheet, they show how to terminate the ECL outputs to drive 50Ω ...
0
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1answer
34 views

Low weight split core transformer on 11kVA transmission line

I've seen transmission line energy harvester's that utilise a split core transformer. Here is an example. However, I fail to see how this is possible when a transformer cores which are small enough ...
0
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1answer
27 views

Calculating power received and V (rms) given powr loss

The transmission line cable below is 10m long and has a power loss of 1 dB/m at the frequency of the source. What is the power received at the receiver (in dBm), and the voltage (RMS) of the signal at ...
1
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1answer
37 views

generator impedance and resistance

If i have a generator with a reactive component and resistive component are these in series of parallel? and When considering the impedance of a transmission line, should the impedance from the ...
2
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1answer
73 views

Understanding Ohm's law(?) for transmission lines

I have this easy schematic Next to this is stated that: $$Vb = \frac{Z_{in1}e_{b}}{R_{B}+Z_{in1}}$$ non Latex-version of the formula: Vb = (eb*Zin1)/(Rb+Zin1) I would like to know from where ...
3
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3answers
175 views

CAN bus layout design

I am trying to design a CAN bus node. The CAN bus shall be split-terminated with 120Ohm, 60Ohm for each line. Therefore i tried using this paper to calculate a characteristic impedance of 60Ohm for a ...
0
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0answers
35 views

difference between rising and falling time from the pulse response of transmission line

Attached is output pulse response of a transmission line (s-parameter). In the high-speed serial link design, we usually see more # of post-cursur ISI than pre-cursor ISI. One of the main reason is ...
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3answers
84 views

Input/output impedance of microcontroller

how to calculate the input and out put impedance for a micro controller , for the purpose of modeling in LT spice , for example RX610 family from Renesas For example the lumped characteristics can ...
3
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1answer
41 views

coupling in transmission line

I have a very basic and rather silly question which I have not found any suitable answer yet. Suppose I have 2 transmission lines. One carrying a high frequency sinusoidal signal. Is there coupling ...
3
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2answers
594 views

High voltage three phase transmission lines

The high voltage transmission lines in North America looks like this. If a three phase balanced circuit uses three voltage sources, would that mean that this pole in figure one is carrying the ...
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2answers
169 views

How is a 50Ω “back-termination” accomplished on a scope probe line?

I've just been watching Jim Williams' very excellent video on Measuring Switching Regulator Noise. At 1:58 Jim mentions a "50Ω back termination" in the probe setup that looks something like this (but ...
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0answers
46 views

reflected wave in transmission lines

I am trying to understand reflection in transmission lines. My text book says - Incident Voltage +Reflected Voltage = Transmitted Voltage. Incident Current - Reflected Current = Transmitted Current. ...
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39 views

What does K(k) mean in a transmission line equation

I'm reading through a book I have about transmission line structures. They frequently use the math: $$\frac {K(k)} {K(k')}$$ For instance, characteristic impedance: $$Z_0 = Constant \cdot \frac 1 {\...
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1answer
117 views

Distributed Transmission Line, Characteristic Impedance in AWR Microwave Office

I am trying to design a distributed amplifier in which the parasitic capacitances of a small-signal FET model are linked to inductors to form a distributed line across the drains and gates and I'm ...
0
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2answers
36 views

Redundancy for a databus transmission

I'm going to start a project in my University in a few week. Since it is a collaboration between my University and a very important company I cannot say too much about the project itself. So I try to ...
6
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2answers
312 views

Transmission Line: characteristic impedance matching

The textbook explains a situation in which when you have 2 unmatched transmission lines (different characteristic impedance), you can connect a new line in between such that the input impedance would ...
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3answers
60 views

How does async data transmission actually work?

I think I understand synchronised data transmission between A and B. They share a synchronised clock signal that indicates when the transmitter is sending a bit and the receiver should read the value. ...
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1answer
45 views

How is data transmitted on different media? [closed]

Thinking about computers primarily, I'm trying to get my head around how data is transmitted along various transmission media. In particular, I'm getting confused between the use of electromagnetic ...
3
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1answer
98 views

Running A Webcam 600ft underwater

I doing a bit of research into the concept of using webcams to watch crab and fish traps to solve the problem of hauling up empty traps. Depth 100 fathoms = 600 feet. Obviously wireless won't work. ...
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1answer
104 views

Simulation of TDR using LTSpice

I'm trying to simulate a TDR based on the figure below, and one of the scenarios is a short circuit. The simulation should last for 140ns. The parameters are \$Z_A = 50 \Omega \$ \$T_A = ...
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1answer
63 views

why step up transformer is used at the generating station to step up the transmission line voltage?

how it helps by stepping up the generating voltage at the generating station to minimize the losses of a transmission line? when voltage increases current also increases. so it should increase the ...
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1answer
69 views

Termination resistors usage

My doubt pertains to the usage of termination resistors. This is a continuation of the discussion I saw in this link - Termination resistor. I understand that any transmission line can be simulated ...
2
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2answers
62 views

Distance on transmission lines traces

I am designing a PCB with a couple of transmission lines. I have already calculated the thickness and width of my traces based on the substrate height and dieletric to have a 50 ohm transmission line, ...
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1answer
69 views

Output Voltage of Quarter Wave transmission line

Consider a 300 ohm lossless line operating at 1GHz which is connected to a source of 10v and impedance of 50 ohm. What is the magnitude of voltage at the open circuit end?. My attempt: At the ...
0
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1answer
65 views

Transmission lines/Antennas power delivered to a load, why halved?

When seeing transmission lines and antennas in class we saw that the power delivered to a load is equal to: $$ P = \frac{1}{2}\cdot \left | I \right |^{2}\cdot Re\left \{ Z \right \} $$ Where I is ...
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2answers
95 views

input impedance of lossless transmission line

can anyone explain this for me? firstly I added up the impedance of transmission lines and found Zin, but it seems to be very wrong. and I don't understand how they came up with these formulas ( ...
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2answers
202 views

BNC cable's characteristic impedance and voltage drop

As far as I understand, the characteristic impedance matters when a signal is oscillating since the BNC coaxial cable can be modeled as having inductors and capacitors as in the figure: I have ...
2
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2answers
139 views

A question about the sound of corona discharge

In my collage, We were doing an experiment of the air's Breakdown voltage . At the end of the experiment we were listening to the sound of corona (electric partial discharge). The power supply has the ...
6
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2answers
638 views

Why skin effect happens at the center of a conductor?

I was reading an article about Skin Effect. I know what skin effect is, but I wanted to know what causes it. Why is the back EMF strongest at the center? Why is it not distributed uniformly at the ...
2
votes
1answer
145 views

No driver IC on net in Hyperlynx problem

I am getting the 'no driver IC on net' problem in Hyperlynx signal integrity software. Does anyone have any idea bout it? This is my PCB: It has an SMD connector and an AD9767 DAC. I have added the ...
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2answers
156 views

Why is AC impedance 1.3 times the DC resistance? [closed]

I have seen several times that AC impedance is considered to be 1.3 or 1.5 times the DC resistance. But, never found the reason behind this consideration. Is it an experimental or observational ...
3
votes
1answer
74 views

Transmission lines and superposition

Below is the circuit in question. Good evening, I'm working on a problem that requires me to graph voltage at point A between -10 ns and 120 ns. I know that we must factor in wave reflections that ...
2
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1answer
61 views

Chamfer Geometry for GCPW and Microstrip

I've seen various "recommended" chamfers for 90 degree grounded coplanar and microstrip traces. For example, or . Is there a "rule of thumb" for which type of chamber and which geometries work best ...
1
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1answer
41 views

Why am I getting different Voltage Losses?

The step-down transformer has a ratio of 10:1 $$P_{globe}=V_{globe}\cdot I_{globe}$$ $$P_{globe}=V_{globe}\cdot I_{globe}=\left( 2 \right)\cdot I_{globe}=4\ \mbox{W}$$ $$I_{globe}=2\; \mbox{A}\; ...
1
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1answer
73 views

Crosstalk Question

Could somebody explain me how could I predict the crosstalk between tracks.From what I know about this are two types of crosstalk: inductive and capacitive.Inductive from what I read is the worst.For ...