- Видео 3
- Просмотров 136 783
Hank Ottey
Добавлен 21 окт 2011
"RF / Antenna Fundamentals in 802.11 WiFi" course promotional video
The link to the course:
www.udemy.com/course/rf-antenna-fundamentals/?referralCode=9A68B80D1FD9BC3F54E7
Topics:
PROPERTIES OF SIGNAL:
Sending
Receiving
Polarization
Wavelength vs. Frequency
Measurement
EIRP (Equivalent Isotropically Radiated Power)
Field Strength vs. Orientation
How Waves Shape Signal
Reflection
Penetration
Diffraction
TYPES OF ANTENNAS:
Omnidirectional
Sector
Directional
ASPECTS OF ANTENNAS:
Signal Spread
Gain
Reciprocity
Range/Antenna Type
Range/Frequency
Mounting
Signal-Spread Morphing
FACTORS OF SIGNAL QUALITY:
Multipath
Obstructions
Fresnel Zone
Weather
Interference
Noise Floor/Signal-to-Noise Ratio
VSWR (Voltage Standing Wave Ratio)
RADIO TRANSCEIVER PROPERTIES:
Data Rate vs. Throughput
Range (Tx Power...
www.udemy.com/course/rf-antenna-fundamentals/?referralCode=9A68B80D1FD9BC3F54E7
Topics:
PROPERTIES OF SIGNAL:
Sending
Receiving
Polarization
Wavelength vs. Frequency
Measurement
EIRP (Equivalent Isotropically Radiated Power)
Field Strength vs. Orientation
How Waves Shape Signal
Reflection
Penetration
Diffraction
TYPES OF ANTENNAS:
Omnidirectional
Sector
Directional
ASPECTS OF ANTENNAS:
Signal Spread
Gain
Reciprocity
Range/Antenna Type
Range/Frequency
Mounting
Signal-Spread Morphing
FACTORS OF SIGNAL QUALITY:
Multipath
Obstructions
Fresnel Zone
Weather
Interference
Noise Floor/Signal-to-Noise Ratio
VSWR (Voltage Standing Wave Ratio)
RADIO TRANSCEIVER PROPERTIES:
Data Rate vs. Throughput
Range (Tx Power...
Просмотров: 921
Видео
Football Explained in 60 Seconds
Просмотров 2,5 тыс.7 лет назад
The intent of this video is to explain American football enough to make it watchable. Certain details were intentionally left out for the sake of simplifying the explanation. Hope you enjoy!
RF and Antenna Basics in 802 11
Просмотров 133 тыс.9 лет назад
This video is intended for those looking to learn the basics of RF and antennas and how they apply to 802.11 wireless systems. No prior RF knowledge is required. Explanations have been simplified in the interest of conciseness. The link for the full course exam is here: www.udemy.com/course/rf-antenna-fundamentals/?referralCode=9A68B80D1FD9BC3F54E7
Thanks Sir
How could someone destroy a radio card without having it in their hands, and how to totally block or ruin transmissions?
Thanks Hank I don't feel so stupid anymore..😅
Help to rearrange angle to sky of orbital speed of objects recalc time, hr,min,sec, main time window,43 mins ,only til open again. No sign signal time, to data links, cold -158 C. Or 158 C hot, in90 min,orbit, John.
A spin of signal in space, signal multiple times of sattilite in part data, not whole data,so we broadening receiver's over district distance, a part of data only missed circle wave whole data. John.
Best RUclips video I’ve ever watched
Thank you!!! Best explanation.
This video is abnormally informative. Never expected that such a clear explaination exists on internet.
@murtazawi.ch1 Thank you very much!! So glad the video was informative for you. Your comment really made my day :)
Very informative! Thanks.
Shut that damn background noise. What the hell are you doing.
Fantastic video. Thanks mate! It clears a lot hard to visualize things for beginner.
Excellent work.
Thank you, Nilesh!
@@hankottey338 hello, i am trying to find some information about Folded Dipole antenna. I have information about Dipole and that two poles are not physically touching each other. So there is a electric isolation. But in Folded antenna, two poles are touching. By a folded part. Now, if the charges move in one direction in two half parts ( half parts mean a part where you connect your supply wires ), then the same charges will move into other direction into folded part. Then the em wave emitted by both the parts will nullify each other. Don't understand. In some pictures i was shown that the charges move into same direction. How? I wish to send you that picture. How can I send? I need email address. I can not attach here. Please explain.
Thank you very much Sir, it was really a bliss to listen to you. You presented many compex concepts in the most simplistic way.
very good presentation
Fantastic Video. just watched it all. a great tutorial and very well done Hank.! just subscribed. you are a great teacher with impressive presentation skills. It was a pleasure talking to you today. keep posting more videos. looking forward to them :)
by the way i missed asking, have you explored mounting a 3dBi antenna for mining crypto? :) i have one on top of my house. i can talk to you about it in our next conversation.
Thank so much for making this video, Hank! The quality and clarity of your delivery is absurdly good! I had so many moments where I was like "AH! SO THIS IS HOW IT WORKS". As an EE student, I hope one day I can achieve this level of presentation and technical mastery!
Thank you so much, @vma011! I am very glad the video helped you. Thank you for your compliment, too! All the best! -Hank
Do you think a monopole antenna can be designed to detect a 100hz sine wave with a length of 40-50 cm?
Hmm, maybe in another universe ;)
@@hankottey338 :)
Best video explaining antenna basics i found on youtube yet.
Deep and informative..plz upload video on Network KPIs..thank you
There are many inconsistencies with even the basic concepts. As a teacher I don't recommend to follow this video for any antennas courses.
Thank you for your comment, -- . Can you state the exact inconsistencies? Please do let me know, as I would like the video to be as accurate as possible. Thank you!
This is pretty good.
Thank you, @EmulationofAwesome!
Excellent work!!!
very good video! thank you!
My pleasure, Erik. Really glad you enjoyed it!
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So clear explanation Hank
nice one
Good video ,are there any other AWP videos
First!
Thank you for this lesson
You are quite welcome, P F01!
THANKS SIR. I GAINED MUCH.
My pleasure, sakthivel Periya Muthaiah. Glad the video helped you!
Great video! Thanks for sharing! :)
My pleasure, Neil Arellano!
Very pedagogical work.
Much appreciated, aavellancursos!
thank you!
You're very welcome, Alexandr Petrov!
Well done Sir. Liked.
Thank you, gex geko!
This Will newer ever work Becaus you aculey don't know anything About the things you talk about Why Will this not Work !!! Ther is No ISOTROPIC ANTENNA or EIRP IT'S ALL FIKTIONAL !!
There was an ambient noise in this video that weaken the strength of the content. The back ground music did nothing to enhance the video and did everything to distract from what you were saying. I couldn't make it past 3 min. Sorry, but I hope you have rethought this approach.
Thanks for the feedback, Ross Hollinger. Always appreciated, good or bad! I have taken your advice and made my latest videos without background noise. Cheers, -Hank
Amazing video, its fast pace makes it very interested to watch and learn!
Thanks, Salar Yunis!
There's no electron! Metal is, what gives off-- energy.
vektor-- lighted use, of a tiny hammer-- medical.
thank you! most informative rf video for those with no prior knowledge
Glad to hear this, ryan smith! Thanks for commenting! -Hank
@29:11 is this what happens with our phones? when connection is good(higher connectivity), it uses less power, and when it is bad, the transmit power increases(as connectivity rate decreases). I've wondered why my phone dies so quickly when its searching for service. Correct me if I'm wrong.
Hi Alexander Koran. Thanks for the comment. This is likely the case, although, I am not familiar with the specific chipsets used by every cell phone! Regards, -Hank
something is not clear. so, the electrons in the vertically polarized antenna (electrons oscillating vertically in TX) generates a magnetic field perpendicular to the antenna (in this case in the horizontal plane of TX). when the magnetic field from TX hits other metal metal objects (other antenna) it generates the electrons in the other antenna (in RX) moving up and down. Now, at 4:55 he says "the oscillating electric fields hits electrons in other metal objects...it forces those electrons to oscillate as well." my question: what forces the electrons to oscillate in the other (RX) antenna? because now i got 2 indications from the video. 1, the magnetic field from TX 2, the electric field from TX Can someone clear this up please?
Hi needsomehike. Sorry for the delayed reply. Hopefully I can provide some clarity regarding your question. First of all, the magnetic field is generated around the antenna (as opposed to "perpendicular to the antenna" ...see the 4:14 mark). In addition, this generated magnetic field has a corresponding perpendicular electric field (see the 6:20 mark). The two fields represented here comprise an electromagnetic wave. To answer your question: "what forces the electrons to oscillate in the other (RX) antenna?", the best answer (in my opinion) is the electric field. In the case of an electromagnetic wave, it could be said that both fields cause the oscillation since they are one and the same when in this form. However, if a separate electric field (say, a stationary electric charge, as produced by a single electron) was introduced in the location of an antenna, this would have influence on the electrons in the antenna. In this case, there would be no magnetic field present. I hope this clears things up! -Hank
This is one of the best presentations I’ve seen on the topic. Thanks and keep them coming.
Thanks, CG Ruiz. This means a lot!
Very good video. I am a former 31C2 and a Ham Radio Operator and the information is very accurate and the presentation is excellent. Any more videos coming soon ? Hopefully, yes and soon !! 😉
Realy .. a HAM you say Accuret you say Are you delutional !! Ther is No ISOTROPIC ANTENNA Or EIRP IT's fiktional
Thank you very much, F TR Competitor. That is quite a compliment coming from someone like you!
You need to think of conventional current flow then using the right hand rule.
Hi slap_my_hand. Thank you for watching, and for the comment. I am not sure what is meant by "conventional current flow". Does this mean there is also an "unconventional current flow"? If so, how is each defined? In either case, the fundamental laws of physics would still apply. Specifically, Ampere's Law (magnetic field resulting from electric current) and Faraday's Law (an electric field produced by a changing magnetic field) are what is dictating the mechanics in this situation. Here are some links that give a breakdown of each law: www.maxwells-equations.com/ampere/amperes-law.php www.maxwells-equations.com/faraday/faradays-law.php Thanks again! -Hank
@@hankottey338 Conventional current flow points in the opposite direction of electron flow. In an electeical circuit, it points from the positive terminal of the power supply to the negative terminal. A lot of things in physics are defined with positive charges, including the direction of magnetic field lines. So even if there are only negative electrons in a wire, you think of the movement of imaginary positive charges when you are working with conventional current flow.