how does mobile phone use radio wave propagation?

Question

how is mobile phone modelled

Answer 1

Your question is a bit unclear, but I'm assuming you are wondering how cell phones work.

This is the abbreviated version of a cell phone to cell phone call:

Each mobile phone sends and receives information at a very specific frequency. The electronic circuitry prevents it from intercepting any frequencies other than the one it was designed for. Most cell phones have their own specific frequency, although you may share a frequency with a few other people (the same way that multiple phone calls can go through a single phone line at the same time).

When you call from a cell phone, it sends out a signal to the nearest phone tower. The receiver in the tower can handle every frequency, and thus several thousand calls, all at once. It amplifies the signals and broadcasts them to a satellite. When the satellite receives the signal, it sends it down to the cell phone tower nearest to the phone you are calling. That tower then sends the signal to the target phone at the proper frequency for that phone.

If I'm mistaken in my interpretation of your question, edit it, and I'll try again.

Answer 2

2

Answer 3

The mobile phone is a radio transciever just like a walkie talkie. The only difference is that it is duplexed (meaining you don't have to push a button to talk) it is using a reserved fequency and is communicating (for the most part) digitally with data packets instead of a broadcast analog signal.

When you place a call, your phone sends a signal to the tower asking for permission to connect to the cellular network. The tower assigns your phone (if you are a subscriber in its database, that is) a frequency and time slot to send it's data packets on.
The time slots rotate very fast; many times per second. And as you talk, your phone records what you say, turns it into a digital data packet and when the time slot is right, it fires the packet to the cell tower.
The cell tower then sends the data packet down a T1 line or over a microwave link to a switch which then sends the data packet to another cell tower and to the person on the other mobile phone. The other person's mobile phone receives the data packet and plays the data back as an audio sound.
Needless to say that all this is happening so fast that we are usually inable to detect it with our ears. But on occasion when you get in a place with bad coverage and your connection sounds "choppy", what you are hearing are data packets that have gotten lost somehow.

I hope that is not too technical. I tried to keep it in layman's language.

Answer 4

Mobile phone radiation and health concerns have been raised since the 1990s, especially following the enormous increase in the use of wireless mobile telephony throughout the world (as of August 2005, there were more than 2 billion users worldwide). This is because mobile phones use electromagnetic waves in the microwave range. These concerns have induced a large body of research (both epidemiological and experimental, in non-human animals as well as in humans). Concerns about effects on health have also been raised regarding other digital wireless systems, such as data communication networks.

The results, so far, have been controversial: the majority of epidemiological studies have not found any clear indication of short and medium term health hazards. On the other hand there is extensive literature (see "The Stewart Report" for a survey) on so-called non-thermal effects of weak microwave radiation on biological tissue in animal models or in-vitro, including affecting the growth of certain tumors, cell death, increased permeability of the blood-brain barrier, DNA damage and others, which suggest the possibility of adverse health effects in humans.

Here is the site to where i got this, i hope this helps you.
http://en.wikipedia.org/wiki/Mobile_phone_radiation_and_health

Answer 5

progression on rrabbit's answer. larger frequency radio waves propagate in line-of-sight in easy words. satellite tv for pc communications, GPS, cellphones all must be able to be certain right now the different unit. hindrances contained in the way interrupt communication. it truly is why cellphones continuously drop *#%&@! calls even as you're shifting, something strikes into the way between you and the antenna. decrease frequency waves can "bypass" off of the ionosphere, and shuttle over hindrances, from time to time diverse skips. Examples are AM radio, some ham radio frequencies, CB radio. incredibly low frequency waves (VLF) can surely propagate in water or earth to three quantity, the army makes use of that to broadcast to submerged submarines who can get carry of the signal right now by ability of their hull. the better the frequency, the better assistance you are able to cram into the signal. So fiber optics can carry significantly better information (Has larger bandwidth) than AM radio.