There's some other key technologies that you mentioned that 5G is using, OFDM and channel coding. I think there's some similar familiar. Was it invented specific for 5G technology, or are we just reusing something already there built on top of it? The answer to that question might lie along an imaginary spectrum so to speak. It's a spectrum between absolutely, yes, and no not quite. In that there are some techniques that have existed for quite some time, and 5G utilizes those in the existing or modified form techniques that were also used by some other technologies. Then somewhere in the middle of the spectrum, there are techniques that have existed for some time, but no other technology before 5G was able or willing to use those techniques. All the way at the other end of the spectrum, there are techniques that are indeed invented or redesign fundamentally, specifically for 5G. I can give you one example each of these points along the spectrum. If you think of techniques that were invented a long time ago and were being used by other technologies, something that you already mentioned in fact, OFDM is one thing that comes to mind. OFDM, that is orthogonal frequency-division multiplexing, further technically oriented in the audience, is essentially the method by which you encode your wireless signal when you send it out using your antennae. OFDM has existed if my memory serves me correctly, since the 1950s and it has also been successfully used, not just by ALT, but also by Wi-Fi. At one end of the spectrum, 5G continues to use the same technologies that have been proven to yield a good performance in some of the existing technologies. Towards the middle of the spectrum, let's say technologies that were invented a while ago, but weren't quite used for one or the other reason. One example I can give is another factor that you brought up regarding channel coding. You all know by now what channel coding is at least at a high level. There is a specific channel coding algorithm that 5G uses, It's called LDPC or low density parity check code. We don't need to know the details about it. But the interesting thing about that we might want to keep in mind is once again, if my memory serves me correctly, LDPC as a methodology was invented sometime in the early 1960s. But it was deemed a little bit too complicated to be implemented in reality using the computational power we had back then. Not only that, we did not have any strong use cases that would have justified the complexity introduced by implementation of LDPC, but 5G given that it promises gigabits per second for individual users and terabits per second for network operators. 5G is perhaps the first modern cellular communication technology that can definitely justify introducing the complexity and that is where LDPC makes its entrance on the practical stage. Going to the other end of the spectrum, I can give you a few examples like flexible subcarrier spacing or something called Mini-slot scheduling. Something we haven't learned yet, but the technically oriented in the audience might know about. Once again, you don't need to know what that is. But just keep in mind that it is one of those technologies that were either specifically invented for 5G or just fundamentally redesigned for 5G to function as effectively. If you keep the spectrum in mind, there is one thing that to me as an engineer gives some solid perspective. In that, as I said, some of the techniques like OFDM or LDPC were invented in the 1950s and 60s that is long before a mankind even went to the moon. So the technologies that were invented before we went to the moon are now being utilized in a cutting edge modern day technology that we call 5G. To me, as an engineer, it gives me some good perspective that even if a technique or a technology, when it is invented people say that it doesn't have a lot of applications or doesn't have broad applicability. It is probably because we haven't yet thought of the use cases. We haven't visualized the myriad applications that technique or that solution would facilitate. It is only a matter of time before a technology or technique with genuine merit will find a widespread use, that is a perspective that I find looking at this example. Got it. Some of the very exciting new features that is coming out that you also mentioned, are they all available, are they coming out the same time, or how are they going to be rolling out? The curiosity is definitely understandable. It would be very nice to have those exciting features rolling out all at once, so that on day one, our 5G phones are all-pervasive and all capable. It would be very interesting and very exciting. However, not to pop your bubble, but in general, whenever a similar technology is deployed, it is deployed in phases. That is because operators have to keep in mind a lot of different factors. Factors like whether there is any valid application to leverage that feature. Whether there are enough number of marketable devices that can leverage that feature. Whether the infrastructure vendors who provide the network hardware and software, whether they are ready with that feature. Beyond that, whether the overall economical calculus makes sense for operators to widely deploy and commercialize that feature. These are some of the things that operators have to keep in mind before they decide what features to deploy in what sequence. That is what makes deployment of these features fundamentally phased. Operators will focus on the most impacting feature, which for 5G is eMBB. Then operators in the next few years we'll begin to consider features like massive IoT, URLLC, Cellular-V2X, etc. To answer your question, yes, deployment will be phased and that is because there are multiple reasons that operators have to keep in mind behind making the decisions about what features to deploy when and in what order. Awesome. I think we talk a lot about 5G now, and the other buzzword that came to me, you also mentioned it earlier, is millimeter wave. It's also interesting as well. Is that also part of 5G or it's something else? That's a question that many people have asked me personally before, and the curiosity is fully understandable because the independent exposure that millimeter wave gets almost makes people think that millimeter wave is a different technology altogether it's not 5G. But fact of the matter is millimeter wave is just 5G technology deployed in one specific band. Just like LTE was deployed in different frequency bands or your Wi-Fi home router operates in two bands, 2.4 gigahertz and five gigahertz, but it is nonetheless Wi-Fi. Millimeter wave, just like that, is nevertheless 5G technology, but it is simply deployed in a different frequency band. Then the question might arise, why then does it get so much attention? We don't seem to differently talk about Wi-Fi in 2.4 versus 5 gigahertz, then why so much attention on millimeter wave? Well, there are a few reasons to that end. First one is that millimeter wave, or 5G millimeter wave, I should say, is the first cellular technology to be deployed in that specific frequency band. Before millimeter wave came along, that particular frequency band was being used only for a limited number of services, mostly, a high powered satellite communication. But millimeter wave changes that and it becomes the first cellular technology to be ever deployed and commercialized in that frequency band. Beyond that, being able to operate in that frequency band opens up doors to a lot of unique possibilities. Possibilities regarding what kind of bandwidth we will have access to? What kind of data rates that we can achieve? What kind of latency we can achieve in the millimeter wave link? Those unique possibilities which are different from what 5G and other bands can offer, those are the possibilities that truly enable a 5G to aggressively meet some of the stringent promises that have been made on behalf of 5G. For example, millimeter wave or one millisecond latency that we discussed earlier. Millimeter wave is by default in much better shape to meet that one millisecond latency bound, as compared to five year deployments in certain other bands. Not that the other bands cannot meet it, but millimeter wave, so to speak, has a leg up in that competition and that is one of the dozen other reasons for which millimeter wave garners so much attention that it makes people somehow think that it is a different technology than 5G. Given that, people would be curious about millimeter wave, they would want to understand what millimeter wave is, what makes that proverbial magic happen. I think we are going to dedicate an entire module to discuss what a millimeter wave is, and I think that module is coming right up after this.
