How Does An Antenna Work? | weBoost

Hi my name is Don and I primarily design and test antennas for a living and I'm here today to try to explain to you basically a little bit about how antennas work so the first thing I want to start with is the antenna wire and we call it coaxial cable so the first thing we are going to talk about it what is not coaxial cable this is just normal power cable notice that the lines are parallel to each other this coaxial cable you'll notice that there's a shield on the outside and then there's an insulator and then there's a center conductor, the center conductor is actually what runs the power to the antenna. The reason this is important is how an internal works. So if you have two pieces of wire side-by-side, you have current flow in this direction and current flow in that direction the current flows cancel each other out if you have a piece of coaxial cable this is actually grounded on the outside and the current flows in this direction and the current flows in that direction on the inside and the currents cancel each other out how we gettin intended to work and actually radiate power is to change that so to change that we want to transmit power out to the air so once again you have two pieces of wired and you have current flow in this direction and current flow in that direction a simple dipole antenna like you put on your FM stereo at home is just when you take this wire and split off over in this direction and split it off over this direction and now I still have current flow in this direction and I still have current flow in this direction but if you notice the current flows in the same direction across this plane and that allows us to generate RF energy that leaves like this, and can be received as well. So if you have two pieces of wire side-by-side the electromagnetic energy that is generated from current flow cancel each other out so if I have a wire here and have a wire here, this one we'll call it positive and this one we'll call negative because this was positive in this one's negative you can't get any energy to radiate out because they cancel each other out I think that's pretty simple but if I take and I separate these two wires like this so this is still my feed point down here and I have current flow in this direction and in this direction and I have current flow in this direction and in this direction but every time you have current flow you also have electromagnetic energy so now because I have current flow in the same direction across this plane now I have an energy field that looks like this. I have a high current point here and a low current point here but high voltage point here and when that high voltage point hits they're all that electromagnetic energy jumps off the wire and radiates out into space that's basically how an antenna works, most antennas act very similar to a dipole antenna and that's what this is and remember a dipole antenna you have radiated energy on both sides How does an antenna receive energy? Well like on a cell tower a cell tower is radiating energy just like our antenna here was radiating energy out, well radiated energy also can be received by this same antenna so the antenna captures that energy and then transfers it down to our feed point so we can run into an amplifier or maybe you just plug it straight into your stereo system or on a car stereo you plug it into the back of the car stereo and they all act very similarly. I hope everything that I've explained today was apparent and you understood it and if you have any questions or comments please feel free to leave that and please subscribe to our channel we will be releasing more videos in the future. Have a great day.

Channel: weBoost

Views: 1,125,410

Keywords: how antenna works, how antenna works animation, how an antenna works, how does antenna work, how antennas work, how does an antenna work, antenna basics, how do antennas work, antennas, antenna theory, radio antenna, antenna, electromagnetic energy, radio waves, science, how to, diy, Do It Yourself (Hobby), omni, yagi

Id: PPKEpJEt_cM

Length: 4min 33sec (273 seconds)

Published: Sat Sep 12 2015