Interference and Frequencies (part 1)

Video Activity

Causes of interference and measuring frequency This lesson covers interference which results in the disruption of signals and radio waves. Metal walls, baby monitors and microwaves can all cause disruption of wireless signals. This can be mitigated by changing the frequency. This lesson also discusses frequency; which are bands at which devices com...

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Time
31 hours 29 minutes
Difficulty
Beginner
CEU/CPE
30
Video Description

Causes of interference and measuring frequency This lesson covers interference which results in the disruption of signals and radio waves. Metal walls, baby monitors and microwaves can all cause disruption of wireless signals. This can be mitigated by changing the frequency. This lesson also discusses frequency; which are bands at which devices communicate. Frequency is measured in waves per second and is measured in gigahertz (Ghz).

Video Transcription
00:04
now because our wireless access points can you, with radio waves of these radio waves are susceptible to interference, especially our some of our frequencies, which are on the same bands as some very popular items that we may have in our environment.
00:20
Now,
00:21
interference to our radio waves can come from everything from microwaves, two Cordless phones to baby monitors to metal cabinets or metal fixtures or metal walls essentially anything where our signal can bounce off of or anything that
00:36
is. Also providing a radio frequency on that same range or emitting electromagnetic interference
00:43
can cause interference on our signals, can cause disruption and can cause deform deformities in our signal. And once our signal reaches a certain point, our wireless access points can tolerate a little bit of interference.
00:57
But once it reaches a certain point, then they have to discard those packets and may have toe request them.
01:03
So
01:04
if we're noticing that we have a computer set up and it's connected wirelessly and we know we're within range and we know that we have a good can, we have a good connection most of the time. But some of the times our connection seems to drop and go out and then come back and drop and come out and come keep going in the cycle,
01:23
then we may have some interference going going on.
01:26
Now. This can be mitigated some by changing frequencies. Now, when we talk about changing frequencies we're talking about. Our 2.4 verses are five Gigahertz Band, which we'll talk about in depth and a little bit
01:38
now are 2.4 gigahertz is a very crowded frequency band. There's, ah lot of different electron ICS. There's a lot of different devices that run on this 2.4 gigahertz bans. Very popular things like Cordless phones or baby monitors or garage door openers may all work on our 2.4 gigahertz band,
01:57
and if they do, they're gonna cause interference with our wireless access point.
02:00
We may. Our microwaves may admit a lot of electromagnetic activity, so we may may not be a good idea to set our wireless access point right on top of our microwave or have a microwave in between us and our wireless access point. We may notice that every time we go to warm up some popcorn before we watch Netflix,
02:17
our Netflix stops for a second has to re establish connectivity,
02:22
so
02:23
this may be mitigated by changing the frequencies. It may be mitigated by getting a different device there. Some Cordless phones that don't work on the same 2.4 gigahertz band, so we may want to check and get different Cordless phones for our environment. For our house, we may be able to
02:39
up the gain on our wireless device because the more power that our signals pushing out
02:45
the more can overcome some of that interference. Or we may just move closer to our wiles. Access wireless access point interference can also come in the form of other people setting up wireless access points in our area. If if we're in our own, we're in a house that we have that
03:02
we only closest people to us, our neighbors,
03:06
it may not be as big of a deal before in an office complex or for in an apartment where a lot of other people, or maybe very close in around us than the four people around us that also have wireless access points set up maybe crowding the frequency and maybe providing some interruptions. So want to check that will want to check into changing our frequency to a less crowded frequency
03:24
or doing something we'll talk about later. Which is which is
03:28
modifying what channel were on.
03:31
No,
03:34
we talk about our wireless. We talk about having two major frequency bands.
03:38
We have our 2.4 gigahertz and our five Giga Hertz frequency band. Well, what is the frequency talk? A little science here.
03:47
Frequency is essentially an electromagnetic radio wave.
03:53
And we
03:53
used these radio waves with our wireless access point and we essentially send data along them.
04:00
So
04:01
why do we have numbers? Why do we call them 2.4 gigahertz and five gigahertz band?
04:06
Well,
04:08
Hertz is
04:11
essentially the number of waves per second,
04:15
so we have our radio wave here.
04:18
Ah, hurts is a measure of the number of radio waves, the number of cycles per second that passed over a certain point.
04:28
So we measure how closely together these peaks are, how closely together the peaks in our radio waves are by hurts, because it's the number that passed over a certain point in a certain second
04:41
now
04:42
gigahertz, however, are the number of billions of hertz that passed over a certain point in a certain second in a single second.
04:51
So that's how compressed these these waves are.
04:55
So 2.4 gigahertz, the 2.4 gigahertz band is 2.4 billion cycles per second. That we're pushing out over this frequency and five gigahertz is five billion cycles per second that we're pushing over.
05:11
So when we look at our 2.4
05:14
gigahertz band versus our five gigahertz
05:17
are 2.4 gigahertz and this is extremely stretched out may look something like this.
05:23
By comparison,
05:26
are five gigahertz may look like this?
05:29
What's the difference there? How what does that really matter?
05:31
Well,
05:33
are 2.4 gigahertz band with our different frequencies can go farther than our five gigahertz band, And this is due to the inherent nature of these waves. These radio waves
05:47
as these radio waves encounter obstacles as they encounter other objects. So say we have a wall here,
05:58
radio waves that are that have a lower frequency radio waves that are doing that the waves are spread farther apart and are wider in between them are going to be able to pass through those obstacles even easier than radio waves that are going very that are going
06:16
a lot closer together.
06:18
So the more compressed they are, the harder it is for them to get through that particular that particular object.
06:25
The wider they are, the less
06:28
the less hard it is for them to pass through that particular object and the less they may be susceptible to some interference. You think if I think, for example,
06:38
if passing through this object
06:41
scatters some waves here are scatters this wave here we've essentially the length of this object has, and there's going to be there'll be a lot more waves than a single wave in the distance between, you know, the distance of a wall. But we've essentially destroyed
06:59
an entire wave and 1/2 here. We've fragmented it, or we've disrupted some of the data.
07:03
On the other hand, we only have about
07:08
half of a wave with our 2.4 that we've disrupted here.
07:12
So
07:13
just a little quick
07:15
science science experiment. AARP Science lesson in a nut show are 2.4 gigahertz waves because they're farther apart because we have less cycles per second. They can pass easier through objects, and they can go farther, whereas our five gigahertz waves
07:34
they can't go
07:35
as far as those 2.4 gigahertz because of the nature of the wave. Not anything necessarily to do with wireless access point. Not anything necessarily to do with the amount of game that we're pushing out, but just the plain and simple fact that there's a limitation to. There's an electromagnetic limitation to how far these signals congee
07:56
as we developed different wireless access points as we develop the technologies,
08:01
we developed wireless access points that are better at taking those signals and cleaning them up. They're better reading the data, even if it's fragmented some. So we may say, Oh well,
08:11
10 years ago, the we're using the same frequency. But now I can now my mind distance between my access points or farther. What's the deal? I thought you said there was a limitation. Well, there is. But remember the technology in the wireless access point that pushes the signals that gives them their power and their gain,
08:31
as well as the technology that actually takes the signals
08:33
and tries to interpret data from the signals has gotten better.
08:39
So that's our difference there between our 2.4 gigahertz and our five Giga Hertz frequencies.
08:45
Now we refer to these as bands because our 2.4 gigahertz band and our five gigahertz band have several channels within them,
08:54
channels being sub frequencies along this frequency that we can use
09:01
when we're sending up our wireless access point.
09:03
So if we go into our wireless access point settings and we are using, we're using a 22.11 B or using eight and we're using a 2.4 gigahertz frequency,
09:16
then our wireless access point, unless we manually set the channel is going to search the airways and say, Okay, there's a lot of traffic on Channel One. There's a lot of traffic on Channel 11. I'm going to use Channel six. So what is Channel six?
09:33
Well, Channel six is actually 2.437 gigahertz,
09:39
so it essentially changes the way that this wave is shaped
09:45
that way. This wave versus another wave, which is on the 2.4 gigahertz frequency band on Channel one, Channel one is running at
09:56
2.412
10:00
so it changes the way the waves or shaped so they don't provide. They don't have as much interference between the two.
10:05
So our wireless frequency bands we have two of them 2.4 band and five band, and then within that band we have channels, and those channels equate to
10:18
just additionally, additional megahertz, just changing the shape of the wave a little bit. But we can only change the waves so much because we only have
10:26
we can. We are. We're only given 2.4 through 2.5
10:31
and 2.432 point five can only contain so many numbers.
10:37
So we have to. We can only change That signal wave so much before becomes a different frequency frequency, which we're not allowed to use.
10:43
So that's what that's why we that's what We have different channels, and that's why that's how are different channels. Look
10:50
on our different frequencies,
10:52
but anyway,
10:54
so that's our That's our little science lesson
10:56
are 2.44 Frequency Band is going to have a longer range because of the way our signal shaped, but it's also gonna have more interference because there are more devices. There are more people on the 2.4 frequency band than there will be on the 5.0 frequency band.
11:11
So if we're getting a lot of interference, we're in apartment building in office complex. We may wanna check into
11:18
some of our other options with our 5.5 Giga Hertz frequency
11:22
are five gigahertz Frequency, on the other hand, gives us more data for each radio,
11:28
which makes sense.
11:30
And when we say each radio, we mean each antenna. So we're allowed were able to push more data per radio purple radio wave than we can with the 2.4 gigahertz frequency. And it makes sense because you look at how our way this format,
11:46
well, that we have are more. We have more cycles,
11:50
but our five gigahertz band again is goingto have less distance, and it's gonna beam or expensive eso some of well, it may be more expensive. Some of our devices that can put that can push good 5.0 gigahertz bands maybe more expensive simply before the simply because of the fact that, um,
12:09
wireless access points that have the capability to push
12:11
55 Giga Hertz frequency are less common. 2.4 is the most common wireless frequency used, and the more there is of something the less expensive. There it's gonna be. The more exclusive a product is, the more expensive is gonna be. So you have to watch out for that.
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