Questions tagged [transmission-line]
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 stations to consumers.
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Why is it bad to have unconnected metal areas around PCBs/enclosures for EMI?
I've heard that it is generally bad to have unconnected metal around PCBs due to both safety reasons of charge buildup, but also EMI in the sense that these metal pieces can act as antennas and re ...
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How can I simulate an RF signal as received by an antenna in LTspice?
How can I simulate an RF signal as received by an antenna in LTspice?
I am designing a simple HF RF receiver and want to test it via LTspice. Can I simulate an RF signal as:
A pure voltage source, ...
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Transmission Lines based on proximity skin and self and mutual inductances [closed]
In transmission line the proximity effect and mutual inductance between the two conductors and three conductors are same. Also the skin effect is due to internal flux.
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Why does the voltage double at the end of line in a open transmission line (physical explanation)
I'm seaching a way to explain physically what happens in a wave reflection in a transmission line, if we apply a DC voltage in a open circuit transmission line, the voltage at the doubled.
I saw this ...
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S21 calculation
In this post
It mentioned that there's a factor 2 in S21 value.
But I'm still don't understand why there's a 2 in it.
My schematic is shown below.
Shouldn't S21 = Vout/Vgen?
My question is: where is ...
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How do transmission lines carry low current but high voltage? [closed]
In the image below, you can see the transmission line connected to transformers and current and voltage is transferred from the generating power station at P=IV. Lowering the dissipation of heat or ...
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Matching SMD footprints to transmission line track width
I created a simple transmission line on a PCB (coplanar waveguide) between two SMA connectors.
I obtained the track width based on JLCPCB's Impedance calculator for the 7628 stackup. The track width ...
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What differences in terms of fields does a grounded metal and an unconnected metal object have
I previously asked a question regarding absorption and reflections of waves to metal. But id like to know the differences that say a PCB metal pour that is connected to a signals return path, and a ...
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Transmission Lines and Waveguides - How to calculate Intrinsic Impedance?
I have come across a problem when calculating the attenuation due to conductor losses for circular cross sections:
A circular copper waveguide has a radius of 0.4 cm and is filled with a dielectric ...
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Voltage in the transmission line
In a power transmission line, the voltage at any point in the transmission line (along the length)is said to be the sum of the incident and reflected wave components of voltage. And if it is such then ...
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coplanar waveguide impedance calculation and tolerance
The Ublox Sara R5 System Integration Guide I am following states that a 50 Ohm antenna waveguide design is recommended and provides a couple example designs that achieve this using FR4 dielectric.
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CAN Protocol traced routed with 90 ohm characteristic impedance
I am using ISO1042BDWV in my board. The schematic is given below. I know that the characteristic impedance of the CAN bus is 120 ohm.
The layout team routed CANH and CANL as 90 Ω differential. The CAN ...
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AC Circuit Analysis with Square Wave and Transmission Line
I'd like to solve the AC analysis for a circuit with a square-wave function (with a DC offset, so it goes from 0V to some positive voltage with each step) in series with a resistor and a shorted ...
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Impedance matrix of a GSG probe
I want to design a CPW that allows for high transmission. Therefore, my first guess was to find the impedance of a CPW for the even mode. I have decided to solve it from the ground up. I have used a ...
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Why do these secondary transmission wires coil around the primaries?
All three primary transmission wires in the picture below have smaller wires coiled around them. These smaller wires (secondaries?) connect to a transformer and onto a nearby house. The coils follow ...
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