Questions tagged [radio-frequency]
The radio-frequency tag has no usage guidance.
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Phase Slope Distance Calcuation
After trying to implement IFFT algorithms for phase-based ranging, as outlined in this very interesting and descriptive blog post; I've been getting horrendous results (orders of magnitude inaccurate),...
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Why does this RLC behavior differ from what equations predict?
In order to better understand RLC behavior under current sources, I constructed the simple circuit below and attempted to analyze it. However, my equations do not agree with simulation results.
The ...
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Phase-Based Ranging
I've been reading a lot about Phase-Based Ranging (PBR), and it's all starting to become very intuitive.
BUT; There is one technical, but extremely important, detail that seems to escape me. When the ...
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Are these levels of RF radiation harmful?
I live on the top floor of a building that has four 5G antennas on the roof. The house is curved, and from my viewpoint, I can partially see one of the antennas pointing towards me. Curious about the ...
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Prime operator for sinusoidal testing function in self-term approximation for Thin Wire using Method of Moments (MoM) $s_m^{'}(x_p)$?
I am implementing thin wire method of moments using W.Gibson's "Method of Moments in Electromagnetics". The approximation for self-term using piecewise sinusoidal basis function is given as
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Synchronous phase value for CERN LHC [closed]
How to find out that the value of the synchronous phase for CERN LHC in the case where beams undergo collision, and the RF cavities provide only longitudinal focusing with no net acceleration.
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Slice selection in MRI
Studying MRI, I found that excitation is done by applying B1 (RF) and Gz simultaneously.
But, I think that if those are applied at same time, slice selection cannot be done correctly because Gz will ...
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Book Recommendation about radio frequency antennas and satellites
I have recently obtained a job in the field of radio frequency antennas and satellites, and I am interested in delving deeper into the subject. Could you recommend any books that cover these topics ...
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Why is 180 degree pulse applied after half echo time (TE) in Spin Echo sequence?
The definition of Echo Time from Radiopaedia:
The echo time (TE) refers to the time between the application of the radiofrequency excitation pulse and the peak of the signal induced in the coil. It ...
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Gravitational waves vs ULF Radio waves
During the recent merger of two Neutron stars the lead up to the merger was detected as gravitation waves. This was the merger of two spinning bodies that had very strong magnetic fields and they were ...
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Is the Fourier Transform a reliable way to infer the physical phenomena producing an RF signal?
Consider the following thought experiments:
Scenario 1:
A person standing far away shines 3 light beams at you, each beam having a narrow spectral distribution centered around different frequencies F1,...
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Can I recover the physical wavelengths present in a light source from a time-series measurement of its amplitude?
Consider a mixture of different wavelengths being emitted from the same point (ex: a star). This light consists of a mixture of wavelengths and intensities at each wavelength. When measuring the ...
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What exactly decides the TTC frequency selections of X-band for deep space missions, C band for geostationary , and S band for LEO missions?
Data rates are higher in X-band, but considering free space path loss and atmospheric attenuation(diffraction I'm assuming is significant here), won't lower frequencies stand a better chance? Again, ...
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How to measure time varying electric field strength accurately in space and time?
I would like to know of any techniques that can be used to measure the electric field strength precisely and accurately in both time and space. I know that there will be physical/ practical ...
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Question about CPU manipulation with RF waves [closed]
Is it possible that by sending a specifically modulated RF wave, you can manipulate the flow of electricity to the CPU, and maybe cause binary code Execution? Like typing something like Hello?
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