|What kind of signal does my wireless network produce?|
Is it in the 0.45 - 30MHZ?
| 4:38 pm on Oct 3, 2006 (gmt 0)|
I recently bought a case of compact fluorescent lightbulbs to help reduce the energy comsumption in my home.
The box states "....This product may cause interference to radio equipment and should not be installed near maritime safety communications or other critical navigation or communication equipment operating between 0.45-3.MHz."
Does my wireless network fit into this range?
And while I'm at it, I've often wondered what the signal might look like if I could see it?
A little off topic for this forum, but what about my cell phone?
I don't need full scientific details, but would like to understand a little bit more about how the wireless system works.
| 5:12 pm on Oct 3, 2006 (gmt 0)|
Your wireless network and your cell phone both use frequencies well above this range, in the 800-2400 mHz range (depending on the type of device.)
Your microwave oven is more likely to cause trouble. In fact, (some) WiFi, BlueTooth, many portable (not cell) phones, etc. share the same frequency spectrum as microwave ovens.
When I worked at a Bluetooth company and was working with a spectrum analyzer, you could see on the scope when somebody was heating up lunch. ;)
| 6:07 pm on Oct 3, 2006 (gmt 0)|
Does the range always stay the same? (If I have twenty or so devices, I'm assuming that they won't jump frequencies.)
If I'm using two devices close together, do the ranges work side by side or maybe the lower one rides along with the higher one?
Does the frequency flow around the walls in the house or go through them?
| 6:36 pm on Oct 3, 2006 (gmt 0)|
|Does the range always stay the same? (If I have twenty or so devices, I'm assuming that they won't jump frequencies.) |
All of these devices use "frequency hopping" technology, which helps avoid interference. They transmit on one frequency for a while (typically, a few milliseconds), then "hop" to another one. But these frequencies are all in the same general range. (A few mHz, typically.) The nodes in a network have a means of synching-up so that they follow a pseudo-random sequence of hopping.
So, if you have, say, a WiFi network and a Bluetooth network, (or DIFFERENT WiFi networks) the odds of them colliding are fairly remote. There will only be interference when they happen to land on the same frequency at the same time.
|If I'm using two devices close together, do the ranges work side by side or maybe the lower one rides along with the higher one? |
Not sure what you mean. Most of these technologies also adjust transmitter power, so that if two devices are close together and communicating, the transmitters will use less power than if they are far apart.
|Does the frequency flow around the walls in the house or go through them? |
At these frequencies, they go through the walls, but are attenuated by them. The higher the frequency, the more the attenuation. (An 850mHz cell phone will go through walls better than a higher-frequency PCS phone.) Any of this stuff will work better, for example, in an open office as opposed to one with walls. And metal=bad, so for example if you have concrete floors with an embedded metal mesh, it won't go through the floor.
There's not much "going around" things, but there can be bouncing off of surfaces.
| 6:49 pm on Oct 3, 2006 (gmt 0)|
|the transmitters will use less power than if they are far apart. |
And more when they are separated by larger distances or shielded ..
Which is incedentally why using your cellphone whilst in your car where it is partially shielded from the station it is trying to reach ..results in it boosting it's power output ( wether you are answering a call or making one it's the same ) ..and thus attempting to cook the part of your brain or whatever nearest to the phone ..
Judging by the conversations overheard on most cell phones no matter where one is in the world ..their users need not worry about brain damage affecting them ..and the possiblities of the microwave radiation producing partial sterilisation may only serve to help clear /improve the gene pool ..
| 8:25 am on Oct 4, 2006 (gmt 0)|
>Does the frequency flow around the walls in the house or go through them?
small notice: not frequency, radio waves :-)
frequency can not fly around, like color or taste, it is one of parameters which characterises radio waves...