 Okay, so let's start with the webinar. Good morning again. My name is Tomasz Walenski and I'm a product manager with RF Elements. And today we'll be looking a lot closer at what coverage actually means. And if any time during the webinar you have any questions, feel free. Or actually I would encourage you to write them down into the webinar tool questions section. And I will answer them at the end of the webinar. So let's start. So at RF Elements we provide innovative solutions for a modern-day WISP. Still today the biggest problem of unlicensed WISP networks is interference caused by using gear that is either poorly designed and deployed without any regard to sustainability which is connected to the RF noise produced by these devices. So if only a few people produce noise it might not be a big deal but if everyone does then everybody will suffer sooner or later. At RF Elements we address this problem of RF noise by changing the paradigm of fixed wireless industry. We're setting new industry standards for RF performance, noise rejection and system scalability through our award-winning horn antenna technology with TwiSport ecosystem. Let's go directly to the topic. So these two images show the same scenario but the one on the left shows an overlay of antenna beam width on a map. So the blue area does not really represent the coverage. It simply shows you the section of a circle corresponding to the antenna beam width angle on the map but nothing more really. The image on the right on the other hand is the closest thing to how coverage would look like if the electromagnetic waves were visible. While the electromagnetic waves do not have any color in order to visualize something we obviously need to use a color. Now in this case the more vibrant the red is the stronger the signal is and vice versa. The more faint it is the weaker the signal is. And in the lower right corner you can see the scale of the signal strength. But before we go into the details of coverage it will be useful to debunk the misconceptions about what users may think coverage is or isn't. So let's have a look at the exact it is in the following few slides. Many users understand the coverage of an area is defined by a beam width of an antenna which is simply not true. They are connected to one another but in general they're not the same thing actually not even close. It is important to be clear about this fact because some antenna manufacturers use beam width in place of coverage to give a simple answer to rather complex question which can do more harm than benefit. The usual way to visualize coverage is to plot a pizza slice shaped area where the beam width angle determines the angular width of the coverage and the gain of an antenna determines how far the sector reaches. So inside this area the conventional thinking is that inside this area we have signal coverage and outside it we do not. Simple and clear isn't it? But unfortunately this is a huge over simplification of what coverage really is. The reality is that the various link calculators you might be using or know from your own experience might show some signal strength even if you place the CPE outside the area that is supposedly covered. Now how can that be? I mean something definitely doesn't add up here. So obviously there must be some sort of a mismatch between what is shown and the reality. The coverage is not a digital variable that has value one inside the blue area and zero everywhere else. So if the beam width does not define the coverage what is it then and what is it good for? Beam width is an antenna parameter. It is defined by the decrease of an antenna gain from the boresight by some value. And in Wisp industry this value is either minus 3 or minus 6 dB. Now these numbers are based on historically accepted standard but as such they are arbitrary and closely tied with the maximum gain rather than anything else. And actually it helps you to get an idea. The beam width helps you get an idea what the expected shape of the radiation pattern may be. The beam width is useful information for antenna alignment for example. Now with a very narrow beam width antenna one must be precise when aligning a point to point link because even small deviations can have strong effect on the link performance. And this includes the mounting of the antenna. So narrow beam width antennas should have a sturdy mounting that should be able to withstand windy conditions because even small misalignments can throw the whole link completely off. Although generally there is no strictly point to point or multi-point antenna the beam width is a good indicator what application an antenna might be better for. This the narrow sectors are of course possible also using a narrow beam width antennas but because the higher gain comes with a narrow beam width as the physics of antennas dictate high gain antennas are most used in point to point lengths to squeeze every possible length of distance from a link. In antenna textbooks you can find that minus 3 dB beam width angle marks so-called crossover point of two sectors which is a point where the coverage areas of the two sectors need to overlap to ensure proper functioning of a network. But as with any textbook parameter it depends on the type of application if it's useful and for Wisp industry the usefulness of the sector crossover point is really negligible due to the unregulated nature of Wisp networks in online systems. So we show you a short teaser in the beginning in the first two slides and now that we know that the beam width is just a very crude and inaccurate measure of what coverage is let's have a look at what it really is. There are many parameters that go into visualizing coverage. First the site has certain height above the ground radio has an output power the antenna has specific radiation pattern and down tilt then we need the map data to have enough precision and the information how the access point is oriented in this map. Knowing all these parameters we can project the fields radiated from the antenna onto the map surface and this is what coverage really is. It's a projection of the fields radiated from an antenna including all those parameters on a map surface. It's a visualization of the signal strength on a map. Now you can see that there is no limit to where you can have coverage or not it shows you how the signal strength changes with distance and it has a continuous and smooth decay until the signal strength is below your radio noise floor which obviously sets a definite limit to the distance until which it makes sense to display the coverage at all. The precision of the coverage calculation is limited by the precision of all these input variables. There are some factors which are of course difficult to count in like for example the changing weather or changing the foliage of the trees with the changing season but that's something obviously to consider when using tools that actually do plot the coverage. A good example of coverage visualization is provided by visible light which is also an electromagnetic wave just like the 5 GHz R signal except at much higher frequencies. A circular spotlight on the ground which the light is pointed at is the coverage itself and the flashlight in this case can be compared to an antenna but except the visible light the electromagnetic waves are invisible which makes the visualization of the coverage using the RF signal more obscure. What we can do though is to visualize the RF coverage using a pseudo-color so we assign the strongest signal a certain color in this case red and the weaker the signal gets the more transparent it is. In this example we show the coverage when using 38 degrees symmetrical horn so the dashed lines you can see indicate the 30 degree beam width as minus 6 dB and by now I'm sure it's clear to you why the signal reaches beyond these lines the coverage is a measure of the whole three-dimensional radiation pattern and all the other variables mentioned earlier so you can see that there is no clear border between the area width and the area width out the signal it is a continuous and smooth function of the radiation pattern for you and I the single color with degrees of transparency is actually not easiest thing to work with in practice because it is hard to tell the signal strength at any point but to make this plot more useful in practical life we can actually use more than just one color so if we're already using one why not to use more so the same plot when using five colors instead of just one looks like this now it's much clearer and easier to say where the signal is let's say minus 17 dBm which corresponds to the bright green color or let's say minus 45 dBm close to the red part of the coverage the color helps our eyes to quickly estimate what signal strength can be expected and where but we can actually go even further so if on top of the AP output power and the CPE gain we also know what the channel width is and what is the noise floor in an area or at least have an estimate we can still improve the practical usability of this plot so these are the MCS rate iso surfaces here each color determines the span of MCS rates the link can work with this plot gives you immediate visual information with very clear borders because the edges are very sharp on what the MCS rate you can expect depending on the location of the customer so now you understand all those cases when you were setting up a link and wondered how come you can see the access point which you should not have seen based on the beam width of an antenna you used it is clear now that using the beam width as a coverage approximation is really inaccurate and misleading important to understand that all antennas actually work in a similar fashion so the coverage is basically these elliptically shaped areas as the one shown in this image but of course differing depending on the shape of the radiation pattern so going further we have prepared a few examples of commonly used antennas in the industry to illustrate how the coverage looks based on the real physics-based data and simulation so let's start with sector antennas the traditional sector antenna has a wide radiation pattern and unsurprisingly the coverage is not determined by the beam width you can also see the back radiation and the side lobes that cause all the issues with the collocation of these antennas very clearly in hope of mitigating the collocation issues many wisps turn to all kinds of shields installed to the back of these antennas and while the shield might dampen the back radiation a little bit you see what it does to the rest of the radiation pattern now its shape is rather wild potentially making your life actually more difficult because especially the customers who are close to the edges of the sector can now find themselves out of it so the shields are not a good idea when trying to deal with the noise because for example in this case you can see that the back radiation did not really change much and the main lobe has changed substantially which is undesired our symmetrical horns have no side lobes which is clearly seen from this plot just a nice pale shaped beam pointing forward and let me emphasize again just to make it really really clear that these images are not created in Photoshop by some graphics guy but they're real physics based simulations which is the closest thing to reality you can get same goes for asymmetrical horns here the coverage is shown for the 90 degree asymmetrical RF elements horn and again any antenna would give similar results in terms of that they're multiple MCA zone within the beam width angle and the signal goes also beyond this angle as well similar images can be produced for point-to-point antennas which will show even more obviously that the coverage is much more than beam width alone among all directional antennas dish is the most common one used in the WESP industry here you can see how the coverage looks like using this particular dish now besides the substantial differences between the polarizations in terms of the side lobes and undesired coverage as a result of them you can see that there is a lot happening outside the declared 5 degree beam width again is highlighted by the dashed white lines and further confirming that the coverage of an antenna provides goes way beyond the beam width definition looking at the real coverage plots more can be said about pretty much any antenna and it's really the ultimate indicator of what the coverage is in this case the directional patch array side lobes are very clear as well as the chain width balance each of the polarizations has quite different coverage shape optimized design of RF elements ultradition antenna really helped minimize the side lobes to a large degree but unfortunately the physics of the dish antennas dictate that the side lobes are very hard to avoid completely nevertheless our ultradish is optimized for minimizing the side lobes and here's ultrahorn so no side lobes whatsoever just a single beam and that's it behaves in a similar manner as the flashlight example we've shown before providing a very clean coverage with no side lobes creating unwanted coverage areas moreover its performance is identical in both polarizations which is why there is only one plot so the coverage is really identical for horizontal and vertical polarization which is the case with the symmetrical horns in general so the plots on the previous slides are showing on the aesthetic image of the coverage at one single frequency point now if we calculate the coverage of many frequency points and make it into an animation you can see how the coverage changes with frequency and this is a very important factor for an information for wefts since you use a wide chunk of the spectrum so therefore an antenna performance and in this case we mean the coverage should be ideally stable over the whole bandwidth because a stable coverage means a reliable tool and also a reliable service to your end customers eventually so seeing this animation might not surprise you because you may have experienced in practice that by switching channels you're hoping to use the cleaner bit of the spectrum the results might have been even worse leaving you really scratching your head like what's going on here like I see in the cleaner bit of the spectrum and when I switch to the channel well the performance is even worse now this is exactly what happens when you're changing the channels the radiation pattern is changing a lot with frequency causing the fluctuations and ultimately unreliability of the network and this is the unfortunate property of the patch array sectors in general and not only sectors like any antenna based on the patch array technology and this is what we mean when we say that the coverage is not stable or reliable the frequency dependence of the radiation pattern makes the user experience anything but satisfying and your life as a Wisp constantly busy servicing the links that that change whenever you switch channels this is how RF elements patch array sector performs the coverage fluctuates somewhat as you can see but overall it is much more stable than with most antennas of comparable type now visualizing the coverage like this really tells the story of what a stable coverage should look like and even more so with our horn antennas if our patch array sector was stable horns are super stable within the spectrum and the coverage is virtually unchanging which is what you want from any sector or directional antenna for that matter this is this way you can rely on its performance and provide the headache free service to your customers which is a dream of every Wisp out there symmetrical horn is a very different case from anything else it provides extremely stable coverage within the legal spectrum this is the great advantage of horns as a type of antennas, their stability but do not get fooled I mean not all the horns are that stable by default the horn can be designed to achieve such covered stability but it still takes a considerable effort to achieve down tilt is another functionality of RF elements horns unlike any patch array antenna and from the following slides we will see why the down tilt is a huge factor influencing the coverage area when it comes regarding the patch array sectors or any other antenna with a very narrow radiation pattern in the elevation plane from this animation you can see that anything beyond a few degrees of down tilt makes the patch array practically useless or in other words you lose the coverage almost completely this is the disadvantage of a very narrow radiation pattern in the elevation plane why the sectors require very precise setup of the down tilt and why they are so sensitive to even small deviations which also actually makes them poor sector antennas when in really very mountainous or hilly regions that elevation narrow radiation pattern is simply not able to cover those valleys well asymmetrical horns have a strong advantage of gradual shrinking of the coverage with increasing down tilt while retaining the shape of the covered area and so this smooth coverage area shrinking when increasing the gain from 0 to 25 degrees I mean the down tilt from 0 to 25 degrees is yet another tool or additional functionality in your hands which can help you mitigate the noise your radio sees and respond to changing customer base depending on where the furthest customer is located with symmetrical horns the effect of down tilt is also a totally different game compared to patch array sectors progressively increasing the down tilt you can see just gradual smooth shrinking of the coverage area while its shape is completely preserved so this is yet another advantage of the symmetrical horns by using the down tilt you can dynamically improve the noise conditions in your network by setting the down tilt based on the furthest customer throughput requirements so this way the antenna only delivers and receives the signal as far as necessary here you can see an example of how to use the down tilt if your customers are clustered closer to the site and the competitor ones are further you simply set the down tilt such that the MCS zone you want to provide to your customers covers only your own CPEs now this will help avoid the interference from other CPEs in the area as much as possible and actually this principle is valid in general regardless where the competitive CPEs or any other links might be that might be located simply set the down tilt according to your CPE that is the furthest in the particular sector and if you're wondering how to figure out the down tilt you need to use to leverage this feature our link calculator 2.0 is the right tool for exactly that because it plots the MCS zones directly on the map so let's have a look at it right now I will show you how the new link calculator works and give you a little demo on how to use it and how to arrive at that correct down tilt so let me switch to the link calculator so if you haven't used it before you can access the link calculator from our landing page or element.com and there's a big tile right now or you can access it from the menu on the bottom clicking in the support column clicking on the link calculator and this will bring you the button on the bottom will bring you to the previous version to the old version of the link calculator so to see the new features you have to click this big red button which is shining at you at the top of the map so doing that will get to the calculator if you used it or not depending on that you might have or not seen the video so when I clicked the try new features button if this was my first visit to the site it would automatically show a video playing with the release notes of the new calculator and know that you have to when you watch the whole video until the end after that the pop-up window will disappear and you'll land exactly where I am now so let me highlight the main differences I'll fly through all the features quickly and highlight the differences compared to the previous version so you can edit the location by simply drag and drop any of the AP or CPE or put an address or GPS coordinates whatever you prefer and actually it's also quite useful to use the satellite view when you're fine tuning the placement of either CPE or the AP where you can see all the rules and place the CPE quite accurately and right, so let's go to the AP settings you can select any of our antennas which was already there before but then we also added the sector carried class 520 because many of our customers still use this antenna the major change is that you can now select the channel width which helps increase the accuracy of the results that the calculator shows the gain of the AP antenna is set based on the choice of the antenna from the drop-down menu and you can edit the output power and here you see the sum of the output power and the gain showing you the EIRP so you can stay within the legal limit the height of the antenna is actually not the height above the ground so if an antenna or the AP is on a building so you have to add the height of the building to the height of the tower on which it is attached and put it here for more precision and then you can play with the down tilt as well so the CPE settings and results a major change from the previous version is that now you can select from the list of CPEs of the major manufacturers and in case you do not find the CPE you're using which might happen with the ubiquity CPEs because ubiquity did not cooperate with us and didn't provide us all the data that we need to include these devices into our calculator so you might find yourself you didn't find the CPE you were looking for and for cases like that you should choose either the generic 802.11ac or N-radio which is there for all those cases so some radios do not have an integrated antenna now in that case you can just edit the gain of the CPE depending on what antenna you're using well some of the CPEs still have an integrated antenna in which case you of course cannot edit the gain and if you have an information about what the noise floor is in the area again it's good to punch those numbers in because it will increase the precision of the calculation or the estimate of the results and the height of the CPE is similar so you should enter the height of the building plus the tower if the CPE is on a building the results you're interested in are now highlighted so the received power and the link quality are now highlighted and this is just the link distance the elevation profile graph did not change much the AP is on the left side and the CPE is on the right side and it shows you the line of sight and what the terrain profile is between them which is good for the cases when there is no line of sight for example now we can see that we're on a hill but when I move the CPE even further we can see that link is obstructed which is yet another indicator telling you or making it clear why you have no results in the results section a bigger change also happened in the received power graph and now the y-axis is still the received power in the DBM but the color coding of the graph shows you between what distances you can have a given MCS rate so we can see that now the CPE location is indicated by the vertical blue line and we can see that we can work with MCS-9 up till somewhere around 11.4 km which is a good information for you to know which is also actually by the way shown in the link details so it's 11.5 where this information tells you the maximum range at the MCS you're currently at then you have an option to change the frequency at which the link is working and despite that our antennas are very stable with changing frequency as we've seen it's always good to to punch that number in depending on what channel you use simply again to improve the accuracy as much as possible other than that when you're done with setting up your link you can download your results into a PDF for a future reference and if you're not sure about anything then we have the guide video full tutorial video about the link calculator so now let's switch to the multi this was single CPE version let's now go to the multi-CPE version as advertised now the calculator shows you the MCS zones directly in the map so the pulsating blue area tells you that the calculation is in progress and now we can see the result when we're using the symmetrical horn with 30 degrees being width and I'm not going to go through the settings because they're exactly the same as in the single CPE version the main difference here being that now it's very easy to see as I move the CPE into the yellow zone I have the link quality based on the color coding so it's very quick and easy reference and while the highest MCS rates might be the most interesting ones you can turn on and off any of the MCS zones which is quite a nice feature makes it more interactive and helps you also to pinpoint or focus on one thing if you want to find providing your customers the service with the link quality of MCS 8 you just turn on that particular MCS zone plot and now you see exactly where the borders of the sector are so a few more upgrades here so previously when you wanted to add more CPEs you would have to use this button down here below the CPEs which you can but then there is an additional button directly in the map which makes it a lot more easier and user friendly because if you have more CPEs and still want to add more you would have to scroll all the way down which can be quite annoying and actually the same goes for the results so they're below each CPE settings settings part but also there is a results table directly in the map again that you don't have to scroll all the way down to see how that particular link performs another important thing to realize or to be aware of is that the coverage shown is always valid for the CPE just selected you can recognize it by having inverted colors compared to the rest of the CPEs so currently we have selected the CPE number one so here on the bottom of the map it says for which CPE the coverage is valid so now as I select different CPEs we see that the coverage is not really changing and this is because they're actually the same devices it's the same as the CPE3 or the CPE4 and all of their parameters including the noise floor and the height above the ground are the same so naturally the coverage will be the same and when I select the CPE number two which is a different device having lower gain the coverage will start recalculating again and that's just by because of that it's a different device or even if I changed any height of the CPE1304 it would also change the coverage not substantially but it still would the difference is most visible when the CPE is a different device and now we can see that okay let me turn on more MCS zones the CPE2 works at MCS7 which now corresponds to the displayed coverage the CPE2 is in the yellow zone but looking at the rest of them we can see that well CPE34 should also have MCS7 but they do have MCS9 and that's again just another indicator of or a cue for you as a user to be aware and always look what CPE is the coverage displayed for so when I switch back we'll see that okay now it fits that the CPE34 are in the red zone and the CPE1 is at the edge but still it's already in the orange zone now let's see how can we figure out that down tilt so let's say these are our CPEs and regardless what is surrounding us we want to minimize the noise that the AP actually sees and let's say that we're good with providing the MCS8 to all the customers if I just increase the down tilt of the AP let's say randomly to 13 degrees and we wait a little bit to see what the resulting coverage will be like and now we see that okay the coverage has shrunk naturally as we increase the down tilt actually let me just change this to the same CPE so that we're on the same page okay all the CPEs still have MCS9 and we see that the gap coverage goes still beyond our cluster of customers and it doesn't matter they don't even have to be close to each other it can be again as I said during the presentation you want to set the down tilt based on the furthest customer MCS requirements in that given sector so let's say CPE number 2 and it still works at MCS9 so we can still go further down with the down tilt so we added a few degrees and wait for the result and we see that okay that's pretty fine I would say I mean the MCS of the CPE number 2 is 8 which is what we're shooting for the rest of them have MCS9 which is great because even better but you definitely don't want to push the down tilt too far to the edge so the ideal down tilt in this scenario would be around 17 degrees maybe 16-15 you know if you just want to be safe and all our antennas actually have the scale of the down tilt on the bracket it's easy to actually see what the down tilt is when you're trying to set it up maybe 16 degrees would be just the sweet spot let's see that looks good to me of course there can be CPEs anywhere within your zone too but again it's really just about you can only optimize the coverage for your own CPEs not the competitive ones or any other another thing that is good at the new calculator is that you can use the full screen mode by clicking this icon here in the right upper corner of the map which makes it more user friendly so the whole menu of the AP settings and the CPE settings with the results is included there so it makes it more user friendly to work in this full screen mode if you want to and actually you can also remove the CPEs from the map if you accidentally put more than you wanted just by pressing this X next to the CPE the CPE will be removed now let's go back to the presentation right so here is a QR code which is a shortcut to our new link calculator and just one more thing about the link calculator is that we provide this tool for you for free so and the data the map data we're using for the calculation of the coverage is also free so please take it as it is and have the patience because the map data has limited accuracy especially around water bodies so when you're around a lake or a river the accuracy of the coverage calculation may be lower there and after all in the link calculator we also have a feedback button so if you're if you have any suggestions or are really unhappy with something just let us know and we'll try to incorporate your comments in the next iteration so it is important to have high performance hardware and at the same time it is important to have the understanding of how to use it correctly and how it works which is why user education is important part of our activities now it is one of our many first time in the Wisp industry things that we at our developments can put on display our idea is that only an educated customer can make qualified decisions so we're also very open about myth-busting and because there are many myths and misconceptions in the wireless industry that can create big problems to many users we have our own community rflab.com which is a user forum where you can ask your questions or about our products connect with us get in touch or just search through the questions that were already asked in the past and we're also updating it with all the events we take part in and you can also find a lot of recorded webinars such as this one there and we're present on all the major social media as well so just a trademark disclaimer the third party trademarks are used only to reference compatibility with our rflab products and all the rights of respective trademark owners are reserved