I've read a book on CCNA Wireless, but you really helped me visualize many of the concepts and made them much clearer and easier to understand - Great Video, thanks.
Nice Video Kevin, yet I'd like some concepts fact-checked if you don't mind. 1. Wireless signals typically never use a magnetic field to transmit. They simply turn the electric field 90 degrees. Both in the sending and receiving end. So far as I know, it is very hard/costly to manipulate the magnetic field just for wireless signal transmission 2. Just because 16-QAM has 16 dots doesn't mean you're communicating 4 bits at a time. What these 4 dots provide, are independent channel resources. It really depends on how many dots simultaneously a user/an application uses. I'd assume the wifi standards support sending multiple bits and receiving them at a same time then re-construct them in order but in typical RF world, these dots are mostly used to support more users rather than extend the channel width 3. Simply altering waves does not form a beam. Imaging throwing 2 stones into the same point of a lake at 2 different times, sure the wave will peak and cancel. But they do not form beam towards a specific spacial direction. The key is the physical distance between 2 or multiple antennas. If you alter your wavelength so that it is 2 or 4 times the distance between 2 or more antennas. That creates a beam. Same as if you throw 2 stones into different spots of a lake at the same time. If the frequency is lucky, you will see waterwaves form a higher amplitude beam towards 1 direction. Great Video though. The protocol and possible application parts are right on spot!
Great video, you don't believe if I tell I didn't understand spacial spectrum before your video, even I asked about it from a university professor!!! Thanks a lot!!!
H I , K E V I N --- Q U E S T I O N --- Thanks for your videos on UA-cam; however, I have a question: Starting with WIFI 802.11 A Standard, then B...why not follow alphabetically with C, then D, then E, then F standards, rather than skipping those four letters and jumping from B to G protocols. And, of course, from G we end up going to N and then AC, followed by the upcoming AX, AY, AZ...? Is there a logical reasoning for the system of upgrading with the letters of the alphabet non-consecutively? Thanks, again.
I think OFDM and orthogonality of its subcarriers has nothing to do with electric or magnetic fields in the air. Orthogonality in OFDM terms is such property of adjacent subcarrier that it is mathematically orthogonal within the time period of single symbol, and that's why adjacent subcarriers overlap without causing interferences to each other. This improves spectral density. And the polarization of transmitted signal in the air is different story...
i could use your advise at these cross roads. I studied 5 months for CCNA, took exam & failed by 61 points. Im not interested in developing a career in R & S, i just wanted a strong foundation in networking. My ultimate goal is to be an AZURE architect . I signed up for your Azure Admin course on Udemy. My question- should i continue to pursue CCNA or move on & start pursuing my true goal/dream to become an Azure Architect ??? Mahalo Kele Cortez
Oh my Gosh! Kevin I lost the first hour of your today's video about EIGRP and I was hoping to watch that later! But now that I refreshed the page it says the video is private! How can I possibly watch it dear? It feels like losing 1 million dollar to me. :( Please....
So sorry you missed part of today’s session. However, the recordings of these sessions are going to be edited and turned into a course that we’ll be selling soon. So, while I wanted to do something nice for this community by letting them watch behind the scenes for free during the live recording sessions, no replays are available. I hope you can catch tomorrow’s live session.
While I think the explanation is good, the meaning of orthogonal is too far off point from it's actual meaning in OFDM. Usually I can understand the need to simplify things, but this is a simplification of a different concept insomuch that the concept explained is wrong. OFDM has nothing to do with spacially orthogonal signals. It's frequency orthogonal signals - having to do with amplitude at particular frequencies, not even phase, which may be thought of closer to a spacial angle, but would still be way off. It has nothing to do with the electric or magnetic field in space.
Agreed Rick. The wireless training in my courses does indeed get into the trigonometric meaning of orthogonality, the superposition of the Q and I waves, and how they can be extracted and compared using a Fast Fourier Transform (FFT). The main point of my description of orthogonality in this video is for viewers to understand that waves that are 90 degrees apart, be that a sine wave and a cosine wave, or physically, in the case of polarized glasses, don’t interfere with one another. I hope that helps explain how I chose to approach the introduction to a topic I didn’t fully understand until I took a graduate-level course getting my Electrical Engineering degree.
TYPO: "Spacial Stream" should have been spelled "Spatial Stream" at 11:51. Sorry about that!
Hi Kevin. There was a video you did earlier about OFDM modulation. Is that video still available? You were explaining OFDM by the swimming pool.
Front 8⁶9
Energetic explanation
I've read a book on CCNA Wireless, but you really helped me visualize many of the concepts and made them much clearer and easier to understand - Great Video, thanks.
Love, how precise and technical this is but also relatable. Effective when paired with my studies! Thanks for this!👍🏽
Nice Video Kevin, yet I'd like some concepts fact-checked if you don't mind.
1. Wireless signals typically never use a magnetic field to transmit. They simply turn the electric field 90 degrees. Both in the sending and receiving end. So far as I know, it is very hard/costly to manipulate the magnetic field just for wireless signal transmission
2. Just because 16-QAM has 16 dots doesn't mean you're communicating 4 bits at a time. What these 4 dots provide, are independent channel resources. It really depends on how many dots simultaneously a user/an application uses. I'd assume the wifi standards support sending multiple bits and receiving them at a same time then re-construct them in order but in typical RF world, these dots are mostly used to support more users rather than extend the channel width
3. Simply altering waves does not form a beam. Imaging throwing 2 stones into the same point of a lake at 2 different times, sure the wave will peak and cancel. But they do not form beam towards a specific spacial direction. The key is the physical distance between 2 or multiple antennas. If you alter your wavelength so that it is 2 or 4 times the distance between 2 or more antennas. That creates a beam. Same as if you throw 2 stones into different spots of a lake at the same time. If the frequency is lucky, you will see waterwaves form a higher amplitude beam towards 1 direction.
Great Video though. The protocol and possible application parts are right on spot!
Thanks so much for taking the time to provide such detailed feedback. I truly appreciate it.
I love Kevin’s Training simply superb 👏👏👏
Great video, you don't believe if I tell I didn't understand spacial spectrum before your video, even I asked about it from a university professor!!! Thanks a lot!!!
Very nice! I've read the CCNA wireless book, and I still learned few things new 👍
Great video Kevin! I like your teaching style.
Another great video Kevin! Thanks.
Always informative. Thank you.
I was just reading Kevin Wallace books, had I known about his videos earlier It would be the most delightful encounter
great video Kev
H I , K E V I N --- Q U E S T I O N --- Thanks for your videos on UA-cam; however, I have a question: Starting with WIFI 802.11 A Standard, then B...why not follow alphabetically with C, then D, then E, then F standards, rather than skipping those four letters and jumping from B to G protocols. And, of course, from G we end up going to N and then AC, followed by the upcoming AX, AY, AZ...? Is there a logical reasoning for the system of upgrading with the letters of the alphabet non-consecutively? Thanks, again.
Awesome explanation. Thank you.
Great brother for your valuable information
Thanks so much for free studies
Great video Kevin! Thank you!
Great Video! One thing so - 802.11n also use multiple Spatial Streams:) thats why speed is up to 600 Mbps there
Bro flexed the dope crib too💪
Excellent video, great content!
I think OFDM and orthogonality of its subcarriers has nothing to do with electric or magnetic fields in the air. Orthogonality in OFDM terms is such property of adjacent subcarrier that it is mathematically orthogonal within the time period of single symbol, and that's why adjacent subcarriers overlap without causing interferences to each other. This improves spectral density. And the polarization of transmitted signal in the air is different story...
Is there a VPN source that you recommended? There are several out there like Express VPN etc
i could use your advise at these cross roads. I studied 5 months for CCNA, took exam & failed by 61 points. Im not interested in developing a career in R & S, i just wanted a strong foundation in networking. My ultimate goal is to be an AZURE architect . I signed up for your Azure Admin course on Udemy. My question- should i continue to pursue CCNA or move on & start pursuing my true goal/dream to become an Azure Architect ???
Mahalo
Kele Cortez
this was extremely helpful ty
I love your channel
Combining multiple 20 mhz channels provide higher data rate. How that is possible? Can you explain in layman's language?
God Bless you brother!
2024 Still learning. Thank you!
Thanks for the video =)
Great , Thanks a lot
Oh my Gosh! Kevin I lost the first hour of your today's video about EIGRP and I was hoping to watch that later! But now that I refreshed the page it says the video is private! How can I possibly watch it dear? It feels like losing 1 million dollar to me. :(
Please....
So sorry you missed part of today’s session. However, the recordings of these sessions are going to be edited and turned into a course that we’ll be selling soon. So, while I wanted to do something nice for this community by letting them watch behind the scenes for free during the live recording sessions, no replays are available. I hope you can catch tomorrow’s live session.
@@kwallaceccie Sure dear. I'm looking forward to the whole course. What time is the tomorrow's session, please?
The final ROUTE Master Class session will begin Thursday (9/19/19) at 11:00 AM EDT (EDT is UTC -4). I hope you enjoy the session.
@@kwallaceccie Noted. I'm counting minutes. 🕚
Good stuff :)
My head HURTS now but thanks! 😜
While I think the explanation is good, the meaning of orthogonal is too far off point from it's actual meaning in OFDM. Usually I can understand the need to simplify things, but this is a simplification of a different concept insomuch that the concept explained is wrong. OFDM has nothing to do with spacially orthogonal signals. It's frequency orthogonal signals - having to do with amplitude at particular frequencies, not even phase, which may be thought of closer to a spacial angle, but would still be way off. It has nothing to do with the electric or magnetic field in space.
Agreed Rick. The wireless training in my courses does indeed get into the trigonometric meaning of orthogonality, the superposition of the Q and I waves, and how they can be extracted and compared using a Fast Fourier Transform (FFT). The main point of my description of orthogonality in this video is for viewers to understand that waves that are 90 degrees apart, be that a sine wave and a cosine wave, or physically, in the case of polarized glasses, don’t interfere with one another. I hope that helps explain how I chose to approach the introduction to a topic I didn’t fully understand until I took a graduate-level course getting my Electrical Engineering degree.