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Antenna Guy
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If waves collapse upon detection, how is it that the Friis transmission equation yields accurate results?
Regards,
Bill
Regards,
Bill
Antenna Guy said:If waves collapse upon detection, how is it that the Friis transmission equation yields accurate results?
Regards,
Bill
Marty said:I'm going to quote from Wikipedia here:
"The ideal conditions are almost never achieved in ordinary terrestrial communications, due to obstructions, reflections from buildings, and most importantly reflections from the ground. One situation where the equation is reasonably accurate is in satellite communications when there is negligible atmospheric absorption; another situation is in anechoic chambers specifically designed to minimize reflections."
Antenna Guy said:Returning to the original question: How is it that what supposedly must hold at infinitesimal scale does not hold at macroscopic scale?
Marty said:Don't you mean it the other way around? The Friis equation applies at the macroscopic scale but not when applied the capture of single photons?
Wave collapse refers to the phenomenon where the transmitted wavefront spreads out and becomes less intense as it propagates through a medium. In the Friis transmission equation, this is represented by the term 1/(4πd2), where d is the distance between the transmitter and receiver.
Yes, the Friis transmission equation takes into account wave collapse by including the 1/(4πd2) term, which represents the decrease in signal strength due to the spreading of the wavefront. This term becomes more significant as the distance between the transmitter and receiver increases.
The Friis transmission equation is specifically designed for free space propagation, meaning that there are no obstacles or reflections to interfere with the signal. Other transmission equations may account for obstacles or reflections by including additional terms or parameters.
No, the Friis transmission equation is most commonly used for electromagnetic waves, such as radio waves and light waves. It can also be used for other types of waves, such as sound waves, as long as the medium is free space and there is no interference.
The Friis transmission equation is a simplified model and may not accurately represent real-life scenarios. It assumes a perfect line-of-sight between the transmitter and receiver and does not account for obstacles or reflections. However, in free space conditions, it can provide a good estimate of signal strength and is commonly used in wireless communication systems.