What are high frequencies and what are low frequencies? And for what they are used for?

Just tell me what are they used for and why in particular (means high freq. for some particular function then why not low frequencies there)? (noise tolerance, propagation through obstacles, ease of transmission or reception, loss ect. ) I don't want too much formulas,wave diagrams and bookish concepts. Just explain in plain school level concept. e.g. At sunrise and sunset, the sun looks red because the low frequencies in the Red Orange etc. can pass the dens distance. Why low frequencies ? Also give some practical examples relating computer science or communication so that there will not be any need to read it again and again to recall the concept. There is one thread on CE having question regarding a particular range and antenna but it's too geeky and contains only one range.

Replies

  • Abhishek Rawal
    Abhishek Rawal
    Hey, Sheldon is a geek, ain't he ?? 😉

    Coming to point, High frequency waves can penetrate the matter easily than low frequency waves.
    Low frequency can travel very long distance ( f=1/T) compared to HF but they usually dies in between propagation. Also as i mentioned before, it cannot penetrate matter.
    So, Telecom Co. uses HF waves to transmit the signals.

    Dude, w/o bookish concepts, theories & formulas "Engineering is not possible".
  • SheldonCooper
    SheldonCooper
    Yeah he is a Geek. I am not. We just share a common name and a photograph. Not many other characteristics match.😀
    Coming to the point.
    Why high frequency waves can penetrate the walls? What are used in Wifi and satellite communication? Why low frequencies die in between?
  • Abhishek Rawal
    Abhishek Rawal
    According to plank, E=hv = hc/l.
    l(lemda),As l is high in short waves, Energy will be decreased( Energy & wavelength is inversely proportional).
    So at long distance SWF will fade.

    Again, E=hf as per plank, more the freq more the E. And high E wave can penetrate the matter(conditions applied)
    You can also compare with E=pc.

    Wifi uses RWF.
  • Jeffrey Arulraj
    Jeffrey Arulraj
    Rayleigh's law does hold good here for performance

You are reading an archived discussion.

Related Posts

In FDM, independent signals are translated into different frequency bands using modulation and then all the modulated signals are combined to in a linear summing circuit to form the composite...
Vodafone has already been accepting the Aadhaar Card (the part of UIDAI project) for the new mobile applications in Hyderabad and Vijaywada. But the real big adoption of the new...
And what is mean by the clock signal? Because it is just high or low right?
LG executive has confirmed in an Interview that the LG Nexus Phone with Android 4.2 Key Lime Pie is coming to India by the end of November. There's no word...
I am interested in processor design, and I would like to know how many transistors are in the average processor designed in the last year or so is, and how...