Antennae Placement

Factual Questions
1

I’m curious as to how antennae work, how they transmit information. Specifically, I’m thinking of my wireless router (though I assume it would be the same for all antennae). What I mean is, from what part of the antenna is the signal released, or, since it is a wave, is it released along the length, parallel to the direction that it is pointing.

Should I point an antenna in the direction I want the signal to be the strongest?

I’m asking to consider this question as though I were in the same room and not in using ‘echoes’ of the signal. If I were to apply echoes, would the direction that the antenna is facing make any appreciable difference if one is in the same room?

Secondly, it is my understanding that a wireless signal bounces around my house, going through doors and such and not through the walls (I’m talking about normal 2.whatever Ghz waves here). If this is the case, clearly positioning the antenna would make virtually no difference - why bother to have those swivel-y pointy things that easily break off? (But now, I’m reminded that moving the rabbit ears on an old TV would make a difference… so are signals picked up along the length of antennae?)

Alternatively, are the antennae on my wireless router simply to pick up and not broadcast a signal? In this case, how should they be placed so as to maximize reception?

Maybe the information I’m looking for is too broad and/or too complicated to feasibly explain easily. Anyone know of some good websites (or books, barring textbooks) that I might pursue?

Thanks!

P.S.: I should add that I realize any information garnered here would likely not make any sort of noticeable difference in my coverage- I’m more curious as to the physics of the thing.

2

For the standard “stick” antennas on most routers, the signal is radiated parallel to the antenna. In other words, for best reception your transmitting and receiving antennas should be parallel to each other.

There are zillions of different types of antennas, each with their own radiation characteristics, but almost all routers use what is called a 1/4 wave dipole.

3

Parallel to each other and pointed at each other (-- --) or parallel to each other with the edges pointed in the same direction ( | | )?

4

That one

5

Oops, I guess that wasn’t unambiguous. ( | | ) is the right way.

BTW, the parens around the antenna diagram actually are a pretty good approximation of what the signal strength looks like. If you were to picture a doughnut (Mmm… doughnuts) centered on the antenna, that’s a good visualization of how the signal propagates : http://www.rfcafe.com/references/electrical/antenna_patterns.htm

I think I was wrong in my first answer, the antennas are actually 1/2 wave dipoles (but the alignment is still the same)

6

Hm. Looks like I have some reading to do.

Thanks for the responses & link!