- Видео 4
- Просмотров 195 858
5G Learning
Франция
Добавлен 6 май 2018
I would like to share with you what I am learning about 5G, a revolutionary technology that will change forever the way we interact with other people and with intelligent objects.
Join me in this trek!
Apologies for my limited proficiency in English.
Join me in this trek!
Apologies for my limited proficiency in English.
Видео
A Detailed Introduction to Beamforming
Просмотров 118 тыс.6 лет назад
An introduction to Radio Beamforming, including the basic mathematical expressions that allow to predict the how antenna arrays behave. Just plain trigonometry and basic linear algebra is used. How arrays are able to focus radio signals on the target and filter-out interference.
An Intuitive Introduction to Beamforming
Просмотров 31 тыс.6 лет назад
A gentle introduction to Radio Beamforming, without using Maths. How Beamforming acts. Its potential to steer energy from transmitter to receiver. Its capability to reduce interference.
5G Radio Waves
Просмотров 6 тыс.6 лет назад
Spectral bands, propagation mechanisms and simple methods to estimate the coverage of 5G Radio Waves
In 18:11 you talk about increasing the delay to “steer” the beam a specific angle theta for if the signal is that angle theta from the y axis rather than directly above it, when you say to increase the delay are you increasing the delta T or tau?
thanks
Excuse me at 16:00, why is there two delays considered?
Phased Array Antenna pls
I just think the "observation window" thing is simply explained by the beamwidth, where if you walk over the same transverse distance at low antenna distance you'll see the beam gain variation, whereas at large distance your same observation window will not see much signal variation, because you'll remain close to the maximum gain "center" of the beam. I also suggest that instead of "painting" a 100lambda sphere with the beam factors, you could draw it as a 3D directivity "blob" pattern, and even in dB. But that's a matter of taste, of course!
Your presentations are absolutely brilliant! The progression of the learning curve is excellent, starting with the "mathless", going to the linear array, and ending in the rectangular array.
I am very blessed by this video..I really appreciate this and may God richly bless you as you move forward to make more videos for the benefits of upcoming learners. ❤
Very Good Presentation. ThanKs!
Great explanation! Thank you.
Wonderful explanation
Thank you!
One can only describe this as s top notch brilliant presentation. The presenter respected the audience, where, rather than offering a hand written scribbled page which he himself read, while wavering a pen or a pencil on a hastily drawn sketch, he showed that he was a highly responsible person, who respected the subject and gave it the decor it warranted. Thank you for this video. It always interested me to know whether within the volume of the formed lobes or in any other radiation pattern, do the E/M curled loops of half a wavelength in size, stack above and near each other as they propagate out from the transmitter.? A one megacycle will have large E/M loops but a 5 Giga hertz signal will have small E/M loops. This suggests that stacking of E/M loops must occur as in waveguides and cavity resonators working at the higher modes. where they need to stack " half wavelengths E/M loops above and beside each other. No one seems to describe this activity as the wave propagates out of the antenna and most drawings show the whole lobe or ever growing in size E/M loops which cannot be sustained due to the limitations set up by the permittivity and permeability of the medium to restrict the rate at which the E/M field grwo and decay at the frequency they are launched. One would suggest that in phased array antenna the E/M loops on the periphery of the lobe are phased out while the other in the centre of the lobe remain stacked up with higher power intensity. It would be interesting to discuss and find an algorithm describing the actual stacking of individual E/M loops within the resulting lobe or in other antennas including omnidirectional ones. Stacking is never mentioned in antennas only in waveguides and cavity resonators. but I am confident that "stacking" occurs in antenna propagation.
this helped me "gain" a great intro to beamforming!
Thank you.
You are welcome.
Are there some new videos comming up ? I have an idea , please make a video for Angle of arrival calculations and extraction of useful information by fft of received signal and spatial rotation of the signal to even further reduce the data points , channel estimation for UL/DL , with this data
Thanks for the suggestion. Currently, I have no time to produce new videos.
@@5glearning772 may i ask what are you working on now a days ? just curious
@@mubeenamjad3619 I design and test 5G networks.
In example at time 2:18 the wavelength of 1 GHz is given in correct value. Please note
Damn this is one of the most detail explanation of beamforming. I have taken this class before but barely able to pass
This guy doesn’t seem to understand the topic and is just reading from a textbook.
excelente explicación , hice un repaso de antenas cuando la estudie en la University of Carabobo -Venezuela
Muchas gracias, Arnulfo.
Hi sir, superb video. I have a doudt, what parameters need to consider, in order to decide a weight formula, what is weight exactly
Hi Suresh, thanks for your comment. A weight is a factor that multiplies the signal received from one of the antenna array element. Suppose, for example, that your antenna array includes 5 elements. Then, you need to consider 5 weights, one per antenna element. To process the array signal in reception mode, you add the weighted signals from each antenna element. Technically speaking, you perform a "weighted average" of the signals from the array elements. A similar approach applies to transmission mode. The weights may be complex numbers, i.e. including modulus and argument. The higher the modulus, the more significant will be the signal from the corresponding antenna element. Besides, the argument is used to introduce a phase-difference (i.e. a delay) between the signals from each array element. There are many ways to select the weights. Some of the methods allow to steer the array sensitivity in reception mode, or the radiated power in transmission mode. These methods are collectivelly called "beam-forming". Other methods select the weights to increase the array sensitivity towards the target and set a null in the direction of an interference source (or a jammer). Explaining the detailed procedures to compute the weights takes some time, so unfortunately I cannot delve into this subject in this limited space. I hope that this helps.
Hi, Can anyone tell me please how variable angle affects on beam alignment??
Hi, Alignment accuracy is higher if the target is near to boresight direction (zero degrees azimuth for a 2D antenna). If the target is located far from this direction, the accuracy decreases because the width of the main lobe inevitably increases. In practice, 5G antennas are typically designed to cover an angle of 60° at each side of boresight, with an accuracy on the order of 4°. I hope that this answer your question.
where can I get the codes?
As the simulations from this video are relatively simple, I just used Excel. To translate the equations into code, I would suggest Matlab or one of its clones (Octave, Scilab, etc.). There is also a specific Matlab library dedicated to this subject: Phased Array System Toolbox. It is optional. With this library you can reproduce all the simulations described in this video and much more. It is very easy to use.
This was very really helpful for understanding my academic syllabus I would like to see some other vedios Please do
Glad to know that it is helpful!
I think, I just wasted my money in university for these courses. You have explained this concept to the point and very clear.
Thanks for your comment.
Wonderful presentation, thank you very much for this.
Glad that you liked. Thank you!
good video, although I have a doubt, in the minute 21:50 to 21:60 mathematically why the signal is blocked or attenuated by 30 °
Thanks for your comment. The signal arriving at 30° is attenuated because it is not wanted, it is assumed the interference. Therefore, the weights are computed to attenuate this signal in order to better receive the other one, arriving at an azimuth of 0°. I tried to show through this example that an array can be used to "filter-out" interference. This is used in the receiver of 5G base stations. It is also used in radars.
Your accent is too funny that I can nearly impossible to focus on the content.
can you share ppt ?
Sorry, only the videos are available in this moment.
Hi! Can you please let me know the software that you used for the beamforming simulations you had shown in the video? I mean, is there an easy-to-use and user-friendly software available? If yes, kindly let me know. Plus, did you use an actual acoustic array for coming up with these simulations?
Hi, the simulations that you see are deduced from the basic equations of antenna arrays. I have just used Excel for computation and graphics, although Matlab would be suitable as well. Besides, these are only theoretical calculations. No attempt has been made to build accoustic, radio or optical experiments because, unfortunately, I have currently no time to work in this direction.
hi thanks for the video. any easy formula to calculate the phase delay into each element for uniform reactangular array antenna to steer the beam to the direction we wanted? thank.
Super good video very well explained! Thanks!
Thank you very much!
Can you share the references you used for these videos? Thank you!
I mainly used the following book: Constatine A. Balanis Modern Antenna Handbook 2008 - Wiley In addition, I consulted the following books: Ahmed El-Zooghby Smart Antenna Engineering 2005 - Artech Arik D. Brown Electronically Scanned Arrays 2012 - CRC Press John Litva et al. Digital Beamforming in Wireless Communication 1977 - Artech Hubregt J. Visser Array and Phased Array Antenna Basics 2005 - Wiley Robert A. Monzigo et al. Introduction to Adaptive Arrays 2011 - SciTech Publishing Zhizhang Chen at al. Introduction to Directio of Arrival Estimation 2010 Artech R. C. Hansen Phased Array Antennas 1998 - Wiley I hope that this may help.
Great lecture of a hot research topic. Is it reasonable to apply similar concepts to the so-called metasurfaces in the optical regime?
Thanks for your comment. The same concepts described for the radio field may be applied to Optics as well. From a practical perspective, it must be remembered that the wavelengths used in 5G radio are in the interval between 1 and 10 cm, hence several orders of magnitude longer than even infrared light. Furthermore, beam-forming at mm wavelengths is currently based on analogue techniques due to today's limitations in semiconductor technology. Therefore, current transceivers in these wavelengths cannot take advantage of the flexibility and richness that digital beam-forming using Fourier transform entails. Of course, this should not discourage research. On the contrary, it is research that paves the way for commercial applications one or two decades later. A final point: in this video we are considering that transmission and reception powers are enough to ensure that a large number of photons are acting. If this is not the case (as happens frequently in Optics), quantum-mechanical effects must be taken into account.
@@5glearning772 Thank you for the detailed response. I will certainly take head of your points in my work. I know time is a precious commodity for people like yourself...but do make more lectures to pass on the knowledge. You have a rare ability of presenting complex things in a clear and simple manner.
Hi, First of all. Thanks for uploading this lecture. This was very informative. At 11.05, the figure notation follows spherical coordinate system. Then why did you said to adopt cartesian coordinate system? I am new to beamforming. I am a little bit confused.
Thanks for your comment. You are right, (r, phi, theta) are spherical coordinates. Sorry for the confusion.
tks very much :))
Welcome!
Great video! Waiting on that video about precoding!
Thank you!
I think u need to learn more on speaking Proficiency than telling us beamforming. Please learn more about 5G cogitative beamforming.
This is so clear. Thanks so much
You are welcome.
Hi, first of all thank you for your excellent lecture. My doubt is how do we suppress the secondary lobes? Do we even need to suppress these secondary lobes at all? Do we use the antenna weights q1,q2 to suppress the side lobes too?
Thanks for your comment. Unfortunately, we cannot suppress the secondary lobes completely with current technology. It is possible to reduce its influence by proper separation between antenna-array elements and parasitic elements, but they still be present. In practical antennas at centimeter wavelengths (as used currently in 5G), secondary lobe gains are usually 10 dB or more below the main lobe. Therefore, even if they may produce some interference on adjacent cells (for example) their influence is small. In millimeter waves, it is feasible to design antenna arrays with e.g. 16 elements (or more). In that case, secondary lobes have very low gain compared to the main lobe and their impact may be considered negligible. Proper selection of antenna weights is mainly used to steer the beam to the target. I hope that these comments may help.
@@5glearning772 thank you for the reply, I get your point now.
hi what are the simulation software that u used to shown all the antenna array performance in the video?
No special simulation tool was used for this video, just Excel.
@@5glearning772 where u guy obtain the array pattern result @12.52
@@boonyang88, it is an application of the array factor equation described in the previous slides. An array of 8 elements is considered. For this animation, the modulus of this factor is presented using logarithmic scale.
You are the GOAT! Thank you man
Thank you!
Great man
Thank you so much!
Make a video on use of aerial basestations in 5G
Thank you for the excellent explanation. Where can I get the matlab code for array factor of linear antenna array for random amplitude and random phase.
Thanks for your comment. You might consider the following book: "Practical Guide to the MIMO Radio Channel with Matlab Examples". Authors: T. Brown, E. De Carvalho, P. Kyristsi ISBN: 978-0-470-99449-8
Another alternative could be chapter 29 of the book "Problem-based Learning in Communication Systems Using Matlab and Simulink" ISBN: 978-1-119-06034-5 Authors: K. Choi, H. Liu I hope that it may help.
Thank you very much
@@adityajvs You are welcome.
Thank you. Through your video, I understood beamforming for reception signal. How about beamforming for tranmission signal?
Beam-forming for transmission is certainly possible and used in many applications (mobile communications, radar, radioastronomy, to name a few). The reason why only reception beam-forming is discussed in the videos is lack of time to fully develop this interesting subject.
Your video solves most of my confusions from university's lectures
Glad to help. Thank you.
@@5glearning772 I have some questions. 1. Is Beamforming only applicable for receiving signal as in your video. How about transmitting signal? 2. Your video takes the examples of up-link. How about down-link case? Do they implement "antenna array" on mobile devices and apply beamforming there? Thank you so much !!!
1. Yes, beam-forming is also used to focus the radiated energy for transmission. 2. In the downlink, the mobile device can be equipped with an antenna array to enhance reception. But in practice only a small number of antennas can be embedded when the operation takes place at cm wavelength. Current 5G devices include 4 reception antennas, so you may consider that a modest reception beam-forming exists at the device. In practice, these antennas are used for MIMO reception (this is another topic). In the uplink, transmission beam-forming could be implemented at the device. But current devices transmit with only one antenna at the same time due to cost-saving considerations (transmission components are relatively expensive and drain significant energy from the small battery). This situation may evolve. If operation takes place at mm waves( e.g 29 GHz), it is feasible to embed a substantial number of antenna elements in the device. Therefore, beam-forming at this side may be used and certainly helps to compensate the high propagation losses at these frequencies. I hope that this answers your questions.
Wow that was good!
Thank you!
Lovely explanation! thanks
Thank you!
Excellent !!!, thank you very much
You are welcome!
Thank you for your excellent presentation I read many popular books (Balanis, Van Trees, Spagnolii) but your explaination of the 2D array factor computation is by far the best one.
Many thanks!
Amazing video. Well done. 👏🏾👏🏾👏🏾👏🏾👏🏾
Thank you!