Now I know all of y'all are familiar with the saying you came in something that you never had and I think the Ravens, that is exactly what it is in this case. Now we remember back when the Ravens they signed Joann James and initially when they signed him I was thinking what are they doing? Doesn't make any sense. Why are you signing this guy just towards ACL? What for? But then they showed the breakdown of the contract and how this year was basically just a $500,000 roster bonus and that was it. And then next year it's like a steal too, especially if he can come back and play and start. And even if he would have played this year, it still would have been a steal and it still would have been relatively cheap. And I was like okay, alright, super low risk, potential high reward. Even if you don't get a high reward, it's a super low risk. Salary ain't nothing crazy. I get it. So they signed him and I was thinking, and we said in a couple of videos, alright, anything that we get out of Joann James, anything we get is a bonus. If they can get anything this year from Joann James, it should be considered a bonus. So what happened? A couple of weeks ago Ray was like, oh, Joann James is practicing. They designated him to return and to start practicing. I was like, oh, oh, okay, man. I didn't want to give my hopes up, but I was still like, oh, okay, he's practicing? What could it mean something? It could. Well, it also couldn't. But I was like, alright, that's a step. And if Ray, and John Harbaugh had said earlier in the season, he said with Joann James, we could maybe get him back in December. And I was like, okay, I didn't believe him. I thought he was just talking, talking, talking. But he ended up practicing December. But the Ravens, they put him back down. And, well, I don't say put him back down, but they took him off the roster. He's going back to the non-football injury list. So with that being said, his season, it's over before it even got started. And it was a long shot with Joann James. It was a super long shot. And we, like, the Ravens, they couldn't have been dependent on him. It wasn't like, alright, hey, Joann James, if he plays this year, that will either make or break off. No, it wasn't anything like that. It was always a luxury. I mean, by the way, the offensive line has been for the most part, I don't think it was a luxury. But it was always considered, like I said, a bonus if he would have gotten to play this year. But of course he didn't. And the Ravens, the offensive line, now they have been better over the past couple of weeks. But at the same time, the play calling has also been better as well. But that's a whole another conversation for a whole another topic. So Joann James, the Ravens, I know we talk about a lot. How a lot of people say, hey, this whole draft this year or next year, it needs to be offensive line and defensive line. And that's it. Of course, you sprinkle in some corner here and there. There's always never have enough pass rushes, even though in this scheme, it's not built for pass rushes to really go off like that. But anyway, I know most people just heavy emphasis on offensive line and defensive line. Now, I do agree with that. But something we have to remember is that the Ravens, they they have an opportunity to possibly now I've said it before and I said again, you still got to treat it like bonuses, but they have an opportunity to possibly get two starters at tackle. See, last year, our problem was the interior of the offensive line. And it seems as if this year they've solved it for now. Well, Ben Cleveland, he'll be here for at least the next three years after this year. Bradley Bozeman, big question mark there because he's getting ready to be a free agent. I think that he's going to not even price himself out of Baltimore. Like, again, I think that that's what Ravens fans like to say to themselves to help comfort themselves when a free agent is getting ready to leave. And they know the Ravens are going to pay him. I just I feel like Bradley Bozeman, I don't know what they're going to do with him. It would be nice to have some consistency at the center position. But at the same time, I could also see them letting him go, letting him walk and he go cash in somewhere else. So we'll see what happens with him. But right now, the interior of the offensive line is actually doing pretty good. Bradley Bozeman, then you got Ben Cleveland and then you got Kevin Zeitler. But it's the tackles that have been a struggle. It's been Tyree Phillips, even though he was supposed to start at God. It's been Alejandro Villanueva not going to get started on that because I know y'all will in the comment section. But your problem went from the outside to the inside, but now it's to the outside again. But now like you have not even a potential solution. But again, you can get two possible starters back next year with Ronnie Stanley coming back off of injury and Jawan James coming back off of injury. Two first round picks, two guys that if they're playing to their level, if they're playing where they have the potential to play at, then they can hold it down. But at the same time, you got to treat it like they're not even coming back. I just feel like with the Ravens and again, it's sad to say because you hate seeing injuries just derail somebody's career. But with the Ravens, with both Jawan James and Ronnie Stanley, I feel like both of them would be bonuses, both of them. If you get anything out of them next year, great, amazing, awesome. But I feel like the Ravens, they have to plan like those guys aren't even coming back. First round pick at tackle. I don't know about all that. I probably wouldn't do that. Second round we talking. Third round we definitely having a conversation. First round though, I don't know about that part. But I feel like they have to address the tackle position early. And not even necessarily that, all right, we got to get a tackle in the second round. We got to get a tackle in the third round. Well, you need to get a quality guy. You need to get a quality guy that can come in and play that has heart as well at the tackle position. You can't just rely on Ronnie Stanley. Sure, he's going to come back and whatnot. That's great. But what's going to happen if you don't have a backup option and he goes down again? Because his ankle is what holds him up. And he's had problems with his ankle. I heard somebody say before he got it cleaned up and he hadn't had the procedure to really go all in and really fix the issue. But this procedure that he recently had, that was to really fix it. And you hope that everything goes super smooth. But you just, you can't rely on him. So you need to plan as if he's not coming back. And Ravens, they got to be really, really smart about it. Really, really smart about it. Because you don't want to find yourself. You don't expect any season to go like this. Because this has been crazy. You don't expect the season to go like this. But you got to plan the best that you can. The best that you possibly can. So that's just what it is. And of course, again, with Joanne James, same thing. You can't fully rely on him to come back. And it's good that he's practicing. So that's a great sign. So he's ahead of schedule and all that. And, well, not really ahead of schedule. He's kind of on schedule. So I did say December. So he's on schedule. But that shows that, all right, he'll be ready. Come training camp and all that good stuff. OTAs, he'll be ready. So that's great. But you just, you still have to have a plan in place. Adjust in case option. So it's important that the Ravens, they take care of that. So again, it would have been nice to have Joanne James on the squad this year. But we get it. We get it. We understand it. There would have been a nice little bonus. But the fact that he won't be playing, it doesn't come as a shock or anything like that. I feel like most people, including myself, have never really expected him to play this year. And if he would have played, oh, great. Awesome. But it wasn't in the expectation. So, like Joanne James is and has been, and now for the rest of the year is officially, I'm out.


Hello, I'm Didier Stavens, a senior handler with the Internet Storm Center. We received a malicious document, an office document that I'm going to look at with HolyDump. And as you can see, it contains macros. But before we start looking into the macros, also remark that here we have a stream that starts ends with the slash o. So this is a frame that contains properties and in F you have the name of the properties and in O you have the value of the properties. And it often happens that malware orders will hide snippets of commands into properties. And here you can see that the size is 2336 bytes, which is a bit large for such an slash o stream. So we are going to look into that stream. I'm selecting it. Okay, yeah. And as you can see here, we have something that looks like base 64 code with a lot of As. So this could be a Unicode and Unicode, yeah, that tells us that it could probably be PowerShell. I can also use a plugin, plugin stream o on this document. And then as you can see, it will extract for you the different property values. And here you can already see also PowerShell encoding. So you can be sure that this is a PowerShell command. So this is base 64 and therefore I'm going to pipe this into my tool base 64 dump. And here stream 12, that's the largest one. So that is the one that we decoded. We can instruct base 64 dump that we want streams to be selected when they have at least 20 characters in them like this. And then you only get that large stream that is listed. So that helps you reduce the clutter on your screen because of course many strings will actually be semantically valid base 64 strings. So I'm selecting this one and I'm doing an ASCII dump. And this indeed looks like base 64. So I'm going to convert this. This looks to be UTF-16 and indeed here we have our PowerShell script where you can see another base 64 string. And here you can see with a little bit of obfuscation, system IO compression deflate stream. So this base 64 string here is compressed data. So I'm going to pipe this again to base 64 dump. And here the longest one is entry 5. So I'm selecting that one. I'm doing an ASCII dump. And here you can see all hexadecimal data. So this looks like it is compressed data. So I'm going to do a binary dump. And pipe this through translate with option F. Option F does a full read. So translate by default operates byte per byte. But if you do slash F dash F, then you let translate operate on the complete file. And what we are going to do here is call function ZLIP because it's ZLIP compression row decompression D. And indeed the data is decompressed. And here you can see another PowerShell script which is a downloader with here one URL that it will download and execute as a PowerShell script. And here is another URL from which it will download and save an exit to disk and then execute that. Now how did I know that this here is compressed data well because of what's in the PowerShell script that it does decompression. There is no ZLIP header here that indicates that this is ZLIP compressed. I will discuss this in an upcoming diary entry. But that is why I'm doing a row ZLIP decompression. So compressed ZLIP without header. If there is a header then you call ZLIP D. But of course you get a narrow here because this one is expecting a header and there is no header.


Everyone and welcome to a courage the cowardly dog horror game titled courage the cowardly PT Now this is based off the horror game PT by the way, just so you guys could know and let's go ahead and press play Okay, so it's courage came home from town. No one was home.  Then he hears a noise go investigate Something freaky is going on here. Okay, so I think I might know the villain they're talking about It's a muriel's nephew Fred Like this weird creepy barber. He's crazy. I think he comes out in the first episode. Okay, so we are in The middle of nowhere. Okay, it's just pretty cool, man You can see the stars the beautiful sky out here in the darkness. We're stranded. Okay, let's go in. Oh Okay, so we are okay. This is not the courageous house is it I gotta get out of here. Oh No, oh No, I don't like that. I'm hearing some creepy noises man. I do got to get out of here. I am getting creeped out Only if courage is here, right? I think we're playing as courage. That would make more sense.  I'm hungry. Just starting out of fridge Okay, so do we go down here? Oh? What's up with that music? I Don't know man. It's give me some creepy vibes Okay, so you don't know the core game PT basically you're like in this house And you keep going over and over through that one door we just went through and every time you go through the door Something strange happens for example this chair this chair is possessed. There was not here before Okay, whatever you go in here.  Who the heck flipped the table over band? It was probably Eustace. Oh, yeah, I forgot nobody's home So it's just me myself and I courage Okay, so it seems like something passed through here and they just knocked some stuff over on the house Let's go through the door again. Let's see what happens. I Think this is the same. I can't even tell the difference. I see no different from the start Okay, the chair is there. Okay, now this entrance is totally blocked dude. What's up with the bed? Like tilted Alright, I guess I don't want is going in there No, the fridge. Oh, I see a key bro. What did they do to the fridge? Hopefully this food in there is still good enough to eat man That is a tragedy. Who would who would unleash their anger out on the fridge, man? Okay, now the comfort tables like the comfort table is trying to have a seat That is actually weird All right, man Door let's go through the door Okay, everything's the same here Nothing seems to change at the start every time. Okay. Now. This is like very barricaded Bro Okay, let's just keep moving then Okay. Oh, there's the key. Okay. What happened to the bed? The bed is no longer here That is kind of strange Wait, can I grab the key or did I grab it already? I can't even tell I think I grabbed it. It's so bright Okay, so I think We grab that key Okay, what happened to the bed, bro? The bed is just God All right, they got a chill out with these jumpscares. Oh Man, wait the bed is is that the bed? I think that is a bed. How the heck did the bed end up over here? What what intonation is going on? Oh Now okay now everything is red All right. This is a little more creepier Than what it was before. Oh Okay, there's a key Wait, we can't grab it though. Okay. There you go. You just have to be precisely on it Okay, I wonder if there's another key over here. No Okay, so everything's the same. It's just that the lighting is red now. Oh, yeah, most definitely All right, we only found one key this time. I wonder if that'll work Wait, what is back to normal? Everything is normal Or is it okay the keys right here? Wonder why we keep finding this key. I mean, I think it's probably to open that door at the end of the hallway but That's pretty much it No jumpscare Am I gonna get jumpscared? I freaking knew it man. I knew that jumpscare was coming Okay, so I don't know what happened to courage as we've seen on that jumpscare He has like He has blood coming out of his eyes and his mouth Maybe he got possessed by a demon or something But I know courage would he would never let himself get possessed He would have found a way to uh To not get possessed Okay, the bread light is back The key okay the keys right here It's so hard to see the key sometimes. It's like it's there, but it's not it's weird Okay, anything in here for me? No Okay, let's just keep moving on go down this way I'm gonna lie this song right here creeps me out Increase me out just a little bit Okay, nothing cool. Let's keep moving Bro, it doesn't stop When is this gonna end?  I don't know why I should grab the key Okay, I think I grabbed it. Yes, I did Bro, I don't think this is ever gonna finish Like a never-ending loop Okay jumpscare 3-2-1 You're not gonna get me bro. I could already tell when the jumpscares are coming Okay, so Do we just like I'm just gonna run towards the door man I'm not gonna grab the key this time Because I feel like every time we grab the key It puts us back to the normal state of the of the house Okay, you know what I am just gonna go through the door. Let's see if this works Okay, it doesn't work. Are you kidding me, bro? Great, so I gotta go Am I dead oh My god, bro Everything is back to normal there you go. Okay, so I don't think I had to I don't know man I think every time we kept collecting the key it kept putting us back. It kept like resetting the floor But as we seen Fred was just jumpscare the crap out of us Okay, I Think this might actually be the end Where are we at? This is different This is not the same room all the end. Thanks for playing All right, you guys whether we have a courage the currently PT Like I love disappointed that the game was fairly short But I mean it was awesome overall because it was a courage the currently dog game and I wish there were more Courage games because I mean if you seen the cartoon, you know, they could make endless Horror games based off of it due to all the monsters they bring out every episode and whatnot. I just feel like people are slacking Man, all right well leave the game link down below so you guys can check it out for yourselves Thank you for watching and I will see you guys in the next one


The Dissemination and Implementation Research Core A research methods core from the Clinical and Translation Science Award at Washington University, in St. Louis Institute of Clinical and Translational Sciences, developed toolkits about dissemination and implementation, D&I, concepts, D&I outcomes, strategies. This paper reports on the development of the toolkits. These toolkits respond to three identified needs for capacity building in D&I research. Resources for investigators new to the D&I field, consolidation of tools and limitations in local contexts. This article was offered by Anna A. Baumann, Alexandra B. Morshed, Rachel G. Tabak and others.


Hello and welcome to today's lecture. So, today let us begin with a new module and instead of directly showing you the contents of the module, I shall start with a simple question, you know. Speed guns, they use Doppler radars to measure the speed of moving vehicles. We discussed about speed guns and you know Doppler radars in our earlier module and by now we know that radar speed guns, it consists of a transmitter and a receiver. If so, what is the concept of a radar speed gun? As in, can phase of a wave be used as a distance measure? Let me give you another example, okay? So, this is of a sonar, you know sonar standing for sound navigation and ranging. It uses the propagation of sound waves to measure distance, that is for ranging and it detects the distance as well as direction of underwater objects through acoustic mains, is not it? But now, I am slightly confused, you know, because my understanding says that an electromagnetic wave consists of an electric and magnetic field oscillating in mutually perpendicular direction. So, for radar and sonar, can phase be used in some manner to estimate distance? Remember, I am not talking about amplitude or wavelength, I am asking you the question, can radar and sonar be used in some manner? As in, can the phase of waves be used in some manner to estimate distance? So, with this background, let me start with today's module. The tagline of module 6 is, can phase be used as a relative distance measure. So, through this module, we will be learning what is radar interferometry, the fundamentals, the interference pattern and few terminologies I will be introducing you to, like the beam width, what is angular resolution and then what is stereosar radar geometry and also whether we can estimate topography, topography from synthetic aperture radar images. Remember, I am asking you whether a two-dimensional synthetic aperture radar image can be used to represent three-dimensional surface of a terrain, topography using radar images and we will also be learning how to interpret an interferogram and what are fringes. You know, these terminologies, they may sound new to you, but rest assured, they will be explained as part of this module as well as you will be having a hands-on session where using SNAP, you will learn how to create an interferogram and how to interpret about interferogram as well as fringes, alright. So, towards the end, we will also discuss about what are digital elevation models, DEMs, how to access them, how to download them and what are its prominent application in the field of water resources engineering and hydrology, okay. So, with this background, let us start with our first lecture of module 6. We discussed about phase of a wave, okay. In our initial lectures, we discussed about different properties that we can derive from a wave, its amplitude, frequency, wavelength and phase of a wave. So, let me reiterate the small videos that we discussed during module 1 showing wave with phase 0 towards your left side and a wave with phase of 90 degree towards your right side. Now, I started this lecture with a question, isn't it, phase as a relative distance measure. So, let us try to understand whether phase of a wave can be used to estimate distance. So, shown in the screen in front of you, you see three markings X, Y and Z, assume that they signify three points, okay. Now, it is well known that phase of a wave changes with distance, okay. Now, assume that we have a wave 1. So, I am going to call it as wave 1 of a certain amplitude and frequency and the wavelength of the wave is given by lambda wavelength of a wave and a wave is say transmitting from a point X to a point Y, okay. So, the distance between X and Y shall be the number of whole wavelengths plus some fraction of wavelength, isn't it? And if we measure the phase of the wave at a location say Y, it may not convey anything much about the distance, but then it shall convey information about the fraction of a wavelength. Now, assume you have two identical waves, okay, two identical waves and say you are measuring the phase at Y and also at another point Z which is at a small distance from Y. So, now the phase which is being measured at point Y will be different and the phase which is measured at point Z shall also be different. Remember, same wave is being measured, but now instead of measuring phase of one wave, we are measuring the phase difference. Now, let me reiterate the question. Does phase difference convey a crucial piece of information about the distance? By distance I mean distance between the two points Y and Z. Now, let us try to understand that, okay. Assume we slowly increase this distance by a small amount, okay. Now, what happens? Now, does the difference phase difference convey a crucial piece of information to you about the distance D? Now, we will be discussing about phase ambiguity slowly when we start interferometry, but for now the concept of path length and phase is very important and we shall be needing this background in understanding this module when we speak about radar interferometry. So, shown here is a relationship that tells you what is the phase difference, okay. So, remember whenever we have two waves which are propagating say in opposite directions, we also discussed in module 1 that they will be subjected to constructive and destructive interference, okay. Waves can interfere constructively leading to an increased amplitude or waves can interfere destructively leading to an amplitude of 0, okay. Now, just to refresh your memory, I know that we discussed these points in module 1, but because we will need all these fundamentals for this section, I am going to reiterate a few of the basic concepts. That waves can interfere constructively and destructively. Now, let us try to understand things a little bit more in detail. Now, you can visualize what will happen when you throw two stones in water, isn't it? Ripples will be created and when you are throwing two or more pebbles at the same time in still water, there will be waves which will interfere constructively or destructively. Similarly, you can think of the analogy using sound waves, sound waves that also tend to interfere constructively and destructively.  Now, before I start assume there are two sources, two sources producing waves in the same direction, okay. And say both the sources are in the same horizontal plane and the waves being emitted are in phase, in the same phase, okay. So, the waves which are being emitted by the two sources, I am going to call it as source 1 and source 2, they are in phase and these waves are having the same frequency and amplitude, they are coherent waves. So, once again, if we consider a point in front of the two sources, you know, in the space in front of the two sources, if we consider one single point, that point is going to be visited by a wave arriving from source 1 as well as another wave arriving from source 2. And there shall be a phase difference between the two waves, isn't it? So, in the video, you can see that I am trying to show you what happens when the properties of a wave are changed, you know, like the amplitude is being changed, what happens to the waves, how do they interfere constructively or destructively. And similarly, you can use the analogy of sound to understand how waves interfere constructively and destructively. So, coming back, now why are we discussing all this? You are coming back to the point. So, if we consider any point in front of these two sources, the phase difference with which both the waves from both sources reach a point can be 0 or it can be some multiple of 2 pi, if they tend to constructively interfere, which means that the resulting amplitude shall be 2a, assuming a is the amplitude of one wave. Now, let me give you the second scenario. At points, now when I say point, it always means point in space which is in front of the two sources emitting radiation. So, at the points wherein the path length is going to differ by half a wavelength, both the waves are going to be out of phase by 180 degrees and they shall be interfering destructively now causing 0 amplitude values. But then, owing to different path length between each point and both the sources, there shall be a phase difference. Now, assume a point that are few wavelengths away from the two sources. Assume a point which is away from both the sources. If you see closely this image, you will be able to notice a regular pattern of peaks and trough, isn't it? Peaks representing high values and trough representing low values. And this pattern, I have shown you a still image, this pattern when you look at it, it will appear to radiate outwards from the two sources in different directions, isn't it? Interference pattern, this is known as interference pattern. Now, let me ask you another question, you know, look at the pattern carefully and then comment on what happens closer to the two sources and what happens farther away from the two sources. I will give it some time, you know. My question is, when you look at this interference pattern in the screen in front of you, what happens closer to the two sources and what happens away from the two sources? You know, closer to the two sources, the pattern may appear slightly complicated, yes? And farther away from the two sources, the pattern appears as a set of radiating beams, okay? So, now is the right time to introduce two terminologies to you known as near field and far field, okay? Near field and far field. Near field is near the two sources that are generating the waves, near field, easy to remember. And far field denotes location that is farther away from the two sources generating the waves, far field. Now, in remote sensing, we are more interested to study about what happens in the far field, isn't it? So, regardless of the distance, any point along the central axis of symmetry shall result in constructive interferences as long as the sources are in phase, okay? And we also refer to this direction as having a look angle of 0 degree. It is also called as, you know, boresight angle or pointing angle. You may have come across this when we were discussing about radar antennas, you know, what are the different types of antennas and what is meant by directional sensitivity. I am just rehydrating a few points. So, remember difference in path length will mean difference in phase, all right? So, I am showing you two interference patterns here, two interference pattern. You can see that both are different, isn't it? If we have the wavelength, even though the path length is same, there shall be twice as many wavelengths which can fit into the same distance. When we have the wavelength, we are doubling the number of beams, okay? Compare between the figures on the left side and the right side. You can see more patterns on the right side, less pattern on the left side, okay? Now, in this context, let me show you a video. Note the frequency and amplitude towards the right side. So, now, I am going to reduce the frequency. Look at how the interference pattern is changing, okay? Look at how the interference pattern is changing. Let me increase the frequency now, okay? Slowly, I am going to increase the frequency and then see for any changes that happens in the interference pattern. I am going to pull the frequency to the maximum possible value, okay? Just to see if there is any change in the interference pattern. Just for you to understand about interference pattern, about boresight angle, about what happens in the near field direction, what happens in the far field direction, alright? So, hold this thought in your mind and let us try to understand whether we can quantify the interference pattern, you know? Visually, I can see the difference in the pattern when I am changing the frequency. Now, how to quantify this pattern? So, by now, we have an understanding that we are more interested to know about the far field solution. And we are interested in considering only about the interference pattern which is far away from the sources, okay? It is not in the distance that is closer to the two sources, but we are more interested to know about what happens to the interference pattern which is far away from the sources. Now, an expression for path length can be written like delta L equal to d sin theta, okay? An expression for path length, d is the distance between the two sources, theta is the angle, delta L is change in path length. Now, the maximum peak occurs only if theta, lambda and d satisfy the following relationship given by theta equals sin inverse n lambda by d. Now, the two sources transmitting waves that were shown as loudspeakers because we were taking the analogy of sound waves. Now, these two sources transmitting waves, they can be considered as two antennas working together in unison. But now, you know, I am a little confused because I can see that from the interference pattern, there are multiple directions in which there is energy radiating. But then, I am more keen to learn about directional sensitivity of an antenna. Our aim is to radiate energy in one narrow direction, okay? So, does it mean that with the two sources or with two antennas, we can steer the interference pattern? Can we change the interference pattern? Isn't it something that is naturally occurring? But then, with the two sources, by some mechanism, can we steer the interference pattern so that the energy gets radiated in a narrow direction? That is what we want to see next. By introducing a phase difference to the signals transmitted from source 1 and source 2, of course, we can make waves to have a phase difference, isn't it? That is what we have been learning so far. But the next question is, can we by some means focus the sensitivity to just one direction? Okay? All right? So, whatever relationships I have written is given in the screen. So, at any point of time, feel free to pause and take a look. The expression for path length is given, D being the separation between two sources, theta being the angle, what angle look angle. And I have also given you the expression wherein maximum in peak occurs if theta, lambda and D satisfy the following relationship, okay? Now, let us try to answer the question. The question was, can we by some means focus the sensitivity to just one direction? So, what we will do is we will try to understand it visually first. The same example of the two sources, emitting waves, have a look at the frequency and amplitude. But this time, I am going to change the separation distance between the two sources, okay? I have stretched it to a maximum value. What happens to the interference pattern? I can see that energy is getting radiated in multiple directions. Now, for a change, let me decrease the distance between the two sources emitting waves. What is happening to the interference pattern? Do you see that energy is radiated more in one particular direction? Directional sensitivity of antennas, you know? The concept of how a radar antenna can be made to be sensitive in certain directions, you know? You get it from here. So, when I change the separation distance between the two sources, there is a change in the interference pattern, which means, yes, I can steer the interference pattern such that the energy gets radiated more in one particular direction instead of it getting scattered in multiple directions, okay? Now, with this background, as part of today's lecture, let me try to introduce two terminologies, okay? Just two terminologies for today. One is angular resolution and the second is beam width, okay? Angular resolution, you may have heard it in parts of module 3 when we were discussing about synthetic aperture radars, okay? Azimuth resolution, range resolution and then somewhere in between I mentioned angular resolution. So, angular resolution of a system shall be defined by how narrow the beam is, okay? How narrow the beam is and the common measure of beam width is given by full width at half maximum, full width at half maximum, okay? Again, look angle is the angle at which first minimum occurs. Now, whenever I mention about these terminologies, recollect the videos I have shown, okay? Look angle, far field, near field, what happens when the distance between the two sources are being changed? What happens when the frequencies are changed? How does the interference pattern look like? What happens when the amplitude is changed? So, remember the videos I showed you, you know, that makes it easy for us to understand and then derive the equations, okay? Now, the reason why we are discussing all these is because these concepts are extremely useful, important to define the pattern formed by an aperture or an antenna, okay? In the far field, a total of n number of waves are there, assume each are having say an amplitude of a and a phase difference of delta phi, assume that in far field, a total of n number of waves exist each of amplitude a and a phase difference of delta phi. The minimum occurs when the waves add in such a way that the result leads to zero amplitude. Minimum occurs when the waves add in such a way that it results in zero amplitude. By definition, you know, this should be when the cumulative angle is 2 phi, is not it? Such that n phi equal to 2 phi, is not it? Think about it. So, let me rephrase the definition a little bit now. The first minimum occurs when the first to last n are exactly in phase again. Then the angle from the center line to the first minimum is given by sin inverse lambda by d. Remember, d is the separation distance between the two sources, lambda is the wavelength, okay? Alright? So, when it comes to an antenna or an aperture as we call it, you may be aware by now that it is a common practice to consider angular resolution instead of beam width, angular resolution and the expression for that is given by angular resolution nearly equal to lambda by d. With this background, we are in a perfect position to understand about what is radar interferometry, which shall be covered in the next part of this lecture. So, in today's lecture, we were pondering on questions as to what happens when two waves which are generated by two sources that are in the same plane separated by a small distance d, what happens to the resulting wave at any point in space in front of the two sources, okay? And then we learnt about interference pattern and what happens to the pattern when I change the distance between the two sources, what happens to the pattern when I change the frequency of a wave, amplitude of a wave and so on. These are fundamental to our understanding of how a three-dimensional topographic information is obtained from two-dimensional synthetic aperture radar images. That was the whole point of, you know, re-iterating the basics once more. So, let me hope that you understood this section of the lecture and I will meet you in the next class. Thank you.


Welcome to JSATV, the newsroom for tech and telecom professionals. I'm Jamie Scott of Kataya, here at Telecom Exchange NYC at the fabulous W. Ho Bokem. Joining me here today, my good friend, Mr. Glenn Johansson, he is the CEO and president of Light River. Glenn, welcome to JSATV. Good morning. Thanks for having me here. Oh, thanks for being here and for being such supporters of, well, us and everything we do. We certainly feel the love and appreciate it. We have a great long-term relationship, so we're thrilled to be here. Yeah, we're so honored. And for our viewers who may not already know, you should know, but just in case, tell us a little bit about Light River. You know, Light River was formed something over 20 years ago with one purpose in mind, and that was to bring the next and best multi-vendor transport solutions to the industry. And so, you know, more than half of us are degree engineers, and we focus on multi-vendor transport solutions, and we provide the hardware, software, and professional services that bring that all together. And I feel like you're being a bit modest. So 2019, banner year for you guys, you're scooping up all the awards. So I have a list, actually. You went to, from PTC, the Lightwave and CRN awards. You were a winner of the Pipeline Innovation Awards, recognizing Netflix, of course, as part of Pipeline's service assurance category. Tell us what makes you so award-winning. You know, I did mention that more than half of us are engineers. So we focus on technology. We focus on innovation, and most of all, we focus on our customers. And because of that, we're always looking forward, and we built kind of a culture of innovation and the next generation solutions. So because of that, we're always thinking about how do we do something different, how do we do it better? How do we better meet the needs of our customers? And that just leads us into new, exciting areas. And the industry tends to recognize folks that innovate. So we're thrilled. You're innovating and from your heart with your customers' needs in mind the whole time, and I can tell that from each one of your team members. And it's really, it's amazing. So tell us a little bit about some exciting projects that you might be working on. So my favorite project right now is that within a month, we'll be moving into the new home for Light River software. So our software product, Netflix, which brings together over 300 different products from, I think, 19 or 20 different vendors over the whole history of transport. It was a product that was actually invented in Bell Labs and spun out as part of Light River a number of years ago. And so we're actually moving back home to the Bell Works facility in Homedale, which was the original Bell Works facility where so many of the technologies that we all take for granted today were actually invented. So within a month we'll be there, we'll be back home in a very exciting new location for us and a great future home of Light River software. You are just turning that building back on a step back in time, but you're also pushing it forward. You guys are going to have a lab. They are yourself, right? Yeah, absolutely. No, it's all about labs. It's all about bringing together all the technologies, the entire history of transport, frankly, and then everything going forward. So it's all about next generation, but also working with the legacy systems that are out there in everyone's networks today, whether it be carriers, utilities, next generation content providers. So thrilled to be right in the heart of the transport industry. Yeah, and we'll also dig in your neighbors too. Highlands moving in as well. So you guys, yeah, we're going to be there all the time. We're trying to get a desk actually over there. So as we approach the middle of 2019, tell us what is next for the next part of the year for Light River? It's one of those such an exciting time. So because we have the knowledge about the hardware and the next generation technologies, and because we have the professional services wrapped around our very innovative factory built network concept where we pre-build, pre-provision networks in our factory, and then rapidly deploy them in the field. And then we wrap it all together with the software. We're able to offer very unique solutions for our customers and bundle together the hardware, the professional services, and the software that really help customers build, design, maintain state-of-the-art transport networks. So you're going to see more and more of those kinds of bundling kind of activities from us this year. Yeah, and I was just talking to Mike Jonas, your friend there, and you guys were being called the glue to our industry. So I think that speaks volumes to what you guys are doing, how critical it is to our network infrastructure ecosystem. So thank you for that. Thank you. Where can our viewers go to learn more? You know, we can always come to www.lightriver.com. Take a look at us online, and that's probably the easiest and fastest way to learn a little bit more about us. Here we go, www.lightriver.com. Glenn, thank you so much for joining us. And thank you viewers for tuning in to JSA TV. Happy networking.