Design 5G Hybrid Beamforming System with MATLAB

Thank you so much, everyone, for joining this session on designing 5G hybrid beamforming system with MATLAB. We welcome you to this session, and nice to have you all here. I'm Uvaraj Natarajan, and I'm from the application engineering group in MathWorks focusing on 5G wireless communication system.

And today, we are going to have an extensive detailed discussion on designing of the hybrid beamforming architecture, as such, what are the various components involved, and what are the functionalities involved, and how to stitch all together to form the complete system. The agenda for today's talk is we'll start with an introduction of the beamforming and the motivation behind it, and we need beamforming in 5G radio. And we will go deeper into what are the various building blocks of the 5G in our system, which helps in building the 5G in our beamforming based system, like the baseband part of it, antenna design, the RF design, and so on.

And next we will jump on to the hybrid beamforming design assets, so how the hybrid beamforming architecture is designed, how that can be done easily using various tools which are available. And then finally, we will touch something on the beam management. So once we are done with the beamforming system, beam management, again, plays a very important role in managing the beam, and how efficiently we manage that is going to be crucial for our success on this as well.

So this is, with respect to today's talk, we will again stop for summary and Q&A at the end of the talk. I'd like to start with one of the customer user stories. So we have MMRFIC, who is our customer, and used the 5G toolbox, along with the phased array and other tool boxes, to build a massive MIMO hybrid beamforming structure for his own project.

So the customer have built the complete end to end beamforming structure starting from the transmitter to the receiver, and he was able to use that particular framework for evaluating his hardware platforms as well as his software algorithms and make use of the same for testing the performance of his algorithms in a realistic scenario, which was simulated.

Coming to the applications and requirements, so 5G as such has a lot of new applications which are coined when compared to LTE or other previous generation communication. And some of the new applications which are coined, like the character vehicles, the Internet of Things, remote medicine, telemetry, smart factories, smart city, virtual reality-- so the various new applications which are coined, and all those applications can be classified into three different buckets.

So one is on the enhanced mobile broadband, which is increasing the complete broadband data rate of the system. And the second one is on the ultra reliable and low latency communication, which we call it as URLLC. And this use case is mainly coined to reduce the latency of the system for very high reliable communications such as vehicle to vehicle communication or telemedicine applications.

And the third bucket is on the massive machine type communications. So this is, again, machines speaking to each other, and which is basically used for applications such as the smart factories, the Industry 4.0, and so on. So with regards to these particular applications, the first one is on increasing the broadband data rate of the complete system message. So what are the technical solutions involved in the increasing of the data rate of the system?

The first one is increasing the bandwidth. Of course, LTE has a maximum bandwidth of 20 millihertz, and if we increase the bandwidth, that is directly proportional to the number of resource blocks which are supported. And hence, the gNodeB will have a flexibility to allocate more data rate, more resources to the users.

The next one is an engineering challenge, which is increasing the spectral efficiency of the complete system. So increasing the spectral efficiency means making the best use of the spectrum, which we have. And that's when our engineering mind comes in the picture, where we need to handle with a lot of optimizations and a lot of changes to enhance the system as such. And flexible air interface using small cells or some of the other options, which we can consider.

And one of the main shift which is happening in 5G with respect to this is going into the higher frequency band that is millimeter wave communications. So currently, till LTE, we are operating in sub 6 gigahertz, and LTE has some frequency bands-- sorry, 5G have some frequency bands carved out in the millimeter wave communication, which is ranging from 25 gigahertz and more. And that has its own challenges as such, so that is when we get the motivation to think about the beamforming as such.

So beamforming-- millimeter wave is basically more sensitive to a lot of effects, such as the blockages, the fading effects, the multipath and the path losses, which happens, obviously, when we are operating on a very higher range of frequency. And that uses a lot of engineering challenges as such, and some of the solutions which we can think of is reducing the size of the cell as such. So that's when small cells and picocells comes in handy for us.

Then we can deploy a cell with a shorter radius, and the problem there again, is we need more cell for covering the same area. So we reduce the size of the cell, we'll get a lot of coverage holes, and we need a lot of cells to cover that as well. So one of the solution, again, that is to create multiple narrow beam in the cell sectors, which basically increases the gain of the system.

So that is when the beamforming comes into picture, and 5G, as we are talking about, millimeter wave communication, beamforming becomes a very natural solution for it, and which gives high directive gain and, hence, increases the throughput of the complete system. So there are various technological enhancements which are done in various part of the protocol stack as well as in the RF and antenna area, which adds value. And combining all those things will help us build the complete beamforming architecture as such.

Let's move to the next part, where we'll talk about multi-domain simulation. So when we are designing the complete system-- so something above the protocol stack deals with the software itself, but something on the protocol stack and below needs a lot of efforts. And it's a multi-domain engineering structure, which we need to design, in order to build the advanced 5G wireless communication system.

And all those subsystems must be designed and tested together. For example, we have the 5G physical layer, which will be, again, building the algorithms, and which can be in HDL or C code, which we are targeting for our FPGA. Or the baseband part of it, which will be next to the physical layer algorithms, and basically, the precoding, which handles the digital beamforming part. And there is also an analog beamforming, which is possible and which has been there in the technological evolution for a long time.

So that is, again, to deal with the RF part of it, where we have real RF components, and we do beamforming from the RF components as such. The next part is on the channel and interferences, so we need to make sure that the channel is modeled perfectly with interferences so that the system is more robust as nature. And combining the analog and digital will give us a solution for hybrid beamforming.

And again, antenna, again, plays a very important role for designing a MIMO antenna system, so we need, again, a lot of capabilities to do that. So this becomes various subsystems, which has to be built together and tested together in order to see how your system performs and evaluate the complete system message. So with that, first, we'll see the first part, which is the physical layer part of it, and which involves the baseband algorithms. So for that, we need to understand the terminologies involved in 5G.

So basically, 5G-- if you are aware of LTE, you'd be easily understanding 5G because it's all enhanced on top of it. For example, we have fixed subcarrier spacing in LTE, and subcarrier spacing is variable in 5G. So there is some kind of flexibility which is introduced, and again, that gives us more flexibility to hold more slots, and again, operate on a different bandwidth.

So waveform generation plays a very important role generating a 5G standard specific, 3GPP standard specific waveform. Plays a crucial role, and that's the first step when you want to build your complete system. So using 5G toolbox waveform generator app, you'd be able to easily generate the waveforms both on the uplink and downlink directions with customizing as per your requirement, like adding multiple bandwidth part, CORSETs, search space configurations, SSBs.

You can also try to implement carrier aggregations for 5G and add the data channel and control channel, as per your requirement. Along with that, you have DMRS, PTRS, and so on. So this gives a very handy off-the-shelf app, which is a very convenient one for you to generate the waveform. And the good part that is you'll be able to export that into various formats. And one specific format which I would like to highlight is exporting to Simulink.

Simulink block is something which will come handy for you when you are designing the complete chain in Simulink. And exporting to Simulink, you'll be able to design the waveform as per your convenience and then export directly to Simulink and then plug it into the complete system. The good part here is you don't want to write any MATLAB code for that. It's available off-shelf for you, and it's great for, again, everyone, and especially for the RF engineers who are basically in need of a ready-made waveform for simulating the RF system. And also if you are looking for integrating to your T&M-based equipment, again, that will be very much handy.

And coming to the next part, which is the precoding and the beamforming part of it. Again, once the baseband waveform is generated, we'll have to compute the precoding matrix and then do complex multiplication with the precoding metrics of the baseband waveform in order to arrive to your digital beamforming. Or on the other hand, you'll have to do certain analog beamforming techniques for making your phase shifters beamformed to the particular direction.

On that note, you might end up exploring the spatial signal processings, and that's where it comes handy. The spatial signal processing is basically very helpful for you to improve the signal-to-noise ratio of complete system by improving a lot of effects of the channel as well as the system assets. And there are various components involved in the spatial signal processing, like the beamforming, the transmit beamforming, receive beamforming, matched filter design, integration of pulses.

And again, estimation of Doppler, your range of operation, and an angle-- so all those are various components which are important when you are thinking about a spatial signal processing assets. And again, eliminating interference is, again, one part of the spatial signal processing, which is again possible using the beamforming array.

Coming specific to beamforming, the phased array system toolbox supports the various beamforming algorithms, which are implemented directly. You have the choice to select the narrowband beamforming or the wideband beamforming, based on the signal that you're operating. And with respect to narrowband beamforming, we have the phase shift beamformer, the MVDR, LCMV beamformers, and so on.

And with respect to the wideband beam formers, you have the GSC, Frost, subband phase shift, or subband MVDR, and so on. So there are various options for you to select. And the good part is you are free to implement your own beamforming algorithm for which you'll get a template of the Phased Array System Toolbox. Once you're done with the system design there, you'll be able to compute and you'll be able to process the result, do various other process things like bit error and constellation diagrams, and so on.

And again, on the receiver side, the direction of arrival estimation is, again, another important factor. We use the beamformer to scan a region. And then we have implemented various DOA, direction of arrival algorithms, both for a specific array geometry or for an arbitrary array geometry, based on your input or based on your equipment. You'll be able to use the inbuilt functions in order to understand the direction of arrival, that is the azimuth and the elevation part of the signal in which it arrives.

This will help you on the receiver side in order to tune into that particular direction for getting that particular beam which you want to tune into. That's with the spatial signal processing algorithms involved. The next one is on the RF design and measurement. We are done with the baseband and the precoding part. The next comes the real RF signals and the RF domain assets.

When we talk about the RF domain assets. The first thing which comes to my mind is RF Budget Analyzer. This is an inbuilt application which is a part of the MATLAB suite. And you'll be able to easily compute various trade-offs in the RF world, design your own RF system, or design a golden reference of your RF components.

If you have a specification from your RF component vendor or a chipset manufacturer, then you'll be able to replicate a part of that directly in the RF Toolbox, and you'll be able to create those components inside that using the RF budget analyzer and then do a circuit envelope simulation on top of it and then create the test range, analyze the trade offs, and so on.

Let me quickly open the app assets. This is the RF Budget Analyzer app. So you'll be able to start designing with a blank canvas or a specific set of receiver or transmitters. Here I have a template with the receiver array with the IF-- sorry, this transmitter array with the IF, the modulator, bandpass filter, the power amplifier effects, and so on.

You'll be able to easily add various components there directly by selecting from the various elements which are available. So you'll be able to add the antenna effects, the experimental models, attenuators, transmission line filters, and so on. Once you're done with cascading your system assets, you'll be able to select those systems and you'll be able to configure the system assets.

For example, can you maybe change the power gain noise figure of my specific amplifier, and see that's getting reflected as a part of the link budget, which is getting calculated. And finally, once you are done with calculating the link budget here, you'll be able to plot the 3D, 2D, or even harmonic balance analyzer S parameters. And then we'll help you to design the complete system with a lot of data which is involved. And finally, you'll be able to export that to various components. For example, you can export to the workspace, or MATLAB script, or even an RF blockset or a test and measurement instrument

One part of export is the circuit envelope model directly, which you will be able to export. And the system automatically creates the headers and footers for you. So it'll automatically create an input signal and the output signal and you'll be able to directly test it. Or if you want to go further down the line, measure the IP2, IP3 of your power amplifier gain, DC offset imbalances, you will have been able to export the same to complete measurement test bench, and then you'll be able to test your system assets.

That's with regards to modeling of the system in the Budget Analyzer app. But once you are done with the modeling of that in the application, you will export that to a MATLAB-based object. So you'll be able to export that to an object called RFB, that is, RF Budget, that you will be able to see the same budget which you have calculated and the nice interactive GUI application. And once your object is ready, you'll be able to input that into another function called RF Systems, which will basically simulate the complete RF system.

For example, we have sent to the RF Budget and created an RF system with these particular components, and we use the RF System, send the transmit waveform into the RF System, and you will be able to receive the waveform out of the RF system, which will give you the real component effect of the complete out RF simulation, rather than doing it in a simulation environment that actually means something. That will take your simulation to the next level, very close to the real environment as possible.

OK. Coming to the next part, which is, again, another interesting aspect, which is the antenna design for the complete 5G system assets. And when we talk about antenna design, the main idea here is to, again, increase the fidelity of your system simulation. The idea here is to move from a simulation environment just by using the simulated functionalities, designing your own real time RF environments, or designing your own antenna as per your requirement and then stitching them together to form the complete system assets.

The Phased Array System Toolbox, as we saw earlier uses pattern superposition. You'll be able to design arrays of antennas and then-- which uses the same pattern for all the elements. But Antenna Toolbox performs a full wave EM analysis where you'll be able to create or design your own antenna as per your own design environment, as per your own antenna vendor's configuration, and plug that into the system simulation, which we are doing. And that will help you to simulate a real antenna effect there. And the result of the designing the antenna can be again plugged into the Phased Array Toolbox to use it for the beamforming purposes.

Let me quickly show you a demo on the Antenna Toolbox search. There are, again, a couple of nice applications. One is Antenna Array Designer and another one is Antenna Designer. So Antenna Array Designer is something which will help you to design an array of antennas. For example, you'll be able to design a linear array, or rectangular array, or even a circular array, which may be your interest.

And also you can specify the array size, for example, and specify an eight cross eight array, or four cross four, and so on as per your convenience. And you'll also be able to select whatever antenna which you are trying to design. For example, I've just selected a basic dipole antenna, but you have various configurations like conical, dipole, fraction, helix, group. So all those kinds of antennas are available. And the good part is if the antenna which you are looking for is not available here, then you'll be able to design a custom antenna as per your convenience also.

You can also design a backing structure for the antenna in case if you don't want to leave it enough space. You'll be able to create a rectangular or spherical backing structure, which will, again, help you to increase the directivity. And you can give your frequency of operation. For example, I just gave 40 here. And then hitting Accept will help you to create a template, a ready made template for you for designing the antenna assets.

The Antenna Toolbox basically helps you to design various array designs like the linear array, rectangular area, or circular array. And it uses a method of movement solver for port, field, and surface analysis. And it also helps in modeling a dielectric substrate with the mutual coupling efforts, effects and then the edge effects and so on.

Coming to subarray. After designing antenna, subarray is, again, a new concept, which was there for a long time and it helps, basically, in compromising between various performance and the complexity of the system. So designing the subarray, you will have to weigh your trade-offs of the system. For example, you have the flexibility to map each RF chain to each transmission element.

Or you also have the flexibility to map the RF chain to only one subset of the transmission element. So depending on the beamforming design or the architecture which you're planning to design, the subarray element configurations would really come into handy to design your own system. And the trade-off here is different realizations have different complexities, and you'll have to weigh it according to the power budget that you have and the antenna, which you are planning to use and then take it forward.

For example, we just saw how to build an antenna in the Antenna Array Designer and using the Sensory Array Analyzer app. Once you're done with that, you'll be able to also analyze the various aspects of the antenna and then replicate the pattern of the antenna to build an array. For example, the sensor array helps you to replicate that and build an array of antennas. And then see the resulting pattern of antenna for the array which you have built and so on.

This is something which you can do in programmatically as well. Using the defaced array commands, you'll be able to create your own custom antenna element, map that to a uniform linear array or rectangular array antenna pattern, and then create a replica of that particular-- for example, here we have the linear array replicated to multiple linear arrays, which forms the subarray and the array of antennas.

This is very much defined in the 3GPP standard as well. The antenna modeling part of the standards speak about defining the antenna elements and the subarrays and so on. So as per standard, you have a subarray element definition, which is of size and crossing. And the same array can be repeated, and the distance between the subarray, both in the horizontal and vertical directions, are very well defined in the standard. And also the polarization of it. So whether you want horizontal polarization or vertical polarization. And then the panel pattern of it. All those things can be simulated using the various features available in the Toolbox.

Finally, the array which you have built using the MATLAB Toolboxes is something similar to what you are seeing as part of this standard definition. This will help you to design a system which is more compliant to the 3GPP standard as well. And on top of that, once you are done with the designing of the system, then you need to do further analysis on top of it.

For example, you'll have to test your beam steering and see how the radiation pattern of the antenna and so on. I have a nice shipping example again. Hold on a minute. So using which, I'll be able to view, visualize the antenna and then place the antenna in a specific location in the world in the map and then analyze the various components of it. For example, in the map which I have here, this is actually an analyzer Site Viewer.

I have placed the transmission antenna here and then various receiving antennas. So I'll be able to steer the beam using the beam steering algorithms, and then based on the topology which you are trying to use, you'll be able to steer the beam and then analyze the impacts of coverage in the beam steering, actually. And then once you are done with the analysis of coverage after the beam steering, you'll be able to, again, analyze various other aspects of the coverage and again the throughput analysis and so on.

Here, once the beam steering analysis is done, we'll jump onto the coverage analysis of the map. For each and every angle in which we were steering the beam, we will analyze the coverage of that particular beam in specific direction. For example, this gives the coverage of one of the beam in one specific direction.

Likewise, we calculate in any specific direction of your choice. And the good part is this map is available for you. So you'll be able to download any specific map from OpenStreetMap, which is openly available for you to download from the internet and then place your receiver antenna and transmit antenna, create your own scene, and create your own antennas and then place the antenna in that particular location and then see how the coverage the next part, which is on the channel models.

Once you're done with the antenna design, the next one is the space. In the simulation environment, of course you're not going to have a real-time transmission. But again, in that note, channel model plays a very important role. This will help you to design the channel and designing your 5G-based channel will help you to make your system more close to the real world environment. That's where the 38.901-based channel models TDL and CDL will come handy for you. You'll be able to add the channel models as per the 5G specification, and then add it to the system simulation to proceed further.

On top of that, you also have various other impairments, which can be added, like free space path loss, or Winner II channel, or even various RF losses due to gas, fog, clouds, and so on. With that, we come to the end of this second chapter. We'll enter into the 5G hybrid beamforming design.

OK, so when we are thinking about hybrid beamforming, we need to understand why we need hybrid beamforming. Hybrid beamforming is basically done in two stages, which is a combination of the analog and the digital beamforming.

Analog beamforming or RF beamforming is basically done through the phase shifters in the RF domain. And again, digital beamforming is done using digital filtering in deep baseband domain. This comes with a nice trade-off, which we have to consider. Designing a beamforming algorithm only in analog or only in digital will make us in trouble because of the power and the complexity-- the computation power required in your system have to be traded off.

For example, you might need a far larger array of antennas. When we talk about MIMO, massive MIMO beamforming, you might need an array of antennas and behind each and every antenna, you need an RF chain and the analog chain actually. And again, on the digital beamforming side, when we are talking about the precoding metrics and the other things. That, again, comes the complexity of computation. So very complex multiplication have to be done there. You need some dedicated resistors and adders and multipliers to do those.

That's again, complexity on the hardware computation capabilities. So hybrid beamforming will help you to come up with an architecture by trading off certain things as per your own system design. And it'll also help you to mitigate the problems which arises due to the power density and dissipation and so on.

Here I have a nice architecture of a hybrid beamforming system. What we have done here is the complete system design and the transmitter part and the receiver part with the channel. We start with the 5G NR transmitter. This is a waveform, which is generated using 5G Toolbox and which is actually Standard specific waveform..

And in this, we also modeled the transmitter array and the receiver array angle. So we give the direction in which they transmit antenna should be steered and the receiver antenna receiving the signal structure. We have a transmitter array hybrid beamforming structure so that we have the implementation of the analog and the digital beamforming. The output of that goes to the channel model where we have the real-time channel effects introduction into the channel model block.

So the output of channel model goes to the receiver, which does the receiving operation, and then calculates the angle of arrival of the system. And then the received signal is, again, fed into the 5G NR receiver to decode the resource blocks and then come up with the bits, which is transmitted in the transmitter.

This becomes an overview of a sample hybrid beamforming architecture. And here we are using a larger array in the transmitter and a smaller array in the receiver for simulation purposes. In this particular transmitter, we are reconsidering four different subarrays on the digital, and again eight batch antennas operating at 66 gigahertz, which adds up to four cross eight, which is 32 antennas in the transmitter side.

And the digital beamforming, here we have the analog of the digital beamforming. The digital beamforming is applied at the azimuth direction and the analog beamforming at the elevation detection. And since we have the four antennas, so these four into eight forms 32 antenna elements, and the beamformers basically uses the beamforming algorithms-- some of the beamforming algorithms, which we saw earlier, and the weighted beamforming is basically used for the digital beamforming. And the two is being input point from the NR transmitter. So this does the multiplication of the waves to the transmitter resource grid. And again, the tapers is added.

And then the other part of the beamformer output is the phase shifting array. This is for the analog beamforming. Here we have four subarrays defined, and each and every subarray has its own RF configuration inside that. And this phase shift input will help it to do the beamforming steering of the phase shift.

Going deeper into the beamformer part, that is the phase shifter part here. So I have the RF domain analysis here. We have the input from the baseband digital beamforming fed into the RF domain, so the cell to RF will convert the Simulink data into an RF domain signal. And we have the IQ modulators and then the power amplifier configurations, and so on. So if you have any specific hardware component, you'll be able to replicate your RF hardware design here. Add your non-linear effects like the IP2, IP3 and the power dividers again help in configuring these parameters.

And you'll also be able to add variable phase shifters. Phase shift is, again, part of the RF blocks. So you'll be able to add the phase shifters. And the input to that would be from the beamformer, which we have design in the previous block. And the output of that, again, goes to the antenna part of it. So here we have a linear array of antennas, which we have designed using Antenna Toolbox. We are embedding that into this system. And this becomes the complete transmission part. And then we are adding a real RF and the antenna effects on top of it.

This gives a big picture of the complete transmission system so that we have the beamformers, the digital beamforming performed, and then the analog beamforming. And on top of that, you'll also be able to add various noise factors. The thermal noise, or the phase noise, or even various non-linearities in channel selections and Interference and so on. And then antenna where we have two different orthogonal arrays of isotropic antennas for estimating the direction of arrivals, actually. The one array we have uses the-- I mean, helps in estimating the elevation and the other one helps in estimating the approximate angle, using which we'll be able to calculate the signal direction.

And here on the receiver side, use root music directional for array algorithm estimation. And this part is for the angle of arrival estimation on the azimuth and elevation. And the same is tapered out for processing the 5G data. So the received signal is, again, converted to digital using ADC and then taken back for the 5G NR processing, the baseband processing of the 5G NR and then get the data back.

This is with respect to the architecture of the complete hybrid beamforming asset. So we have the 5G data which is transmitted and then transmitted over the RF chambers and then the RF blocks, and then adding antenna effects. On top of that, the output of it will be sent to this channel model where we add the channel effects.

And again, in the receiver we have various blocks implemented for the angle of arrival. And then the other part of it goes to the 5G NR receiver, which will do the decoding of the 5G signal and then gets back your message. So that's, again, only baseband signal processing. We have the baseband to baseband complete simulation, including the RF and antenna structures on top of it, which will help you to design the complete 5G NR beamforming-based system as such.

Coming to the next part of the talk, which is mainly on the beam management. Once we are done with designing the beamforming, then we need to manage that beam properly in order to make the system more efficient. On that note, if you see it's a list of procedures starting with beam sweeping.

This is sweeping of the beam both in the transmitted and in the received direction. And beam measurement is the next part. For example, a beam which is transmitted will be measured by the receiver. For example, a beam from gNodeB will be measured by the UE. And basically it determines the best beam to select. So it does a scanning and it determines the best beam, which has to be selected for the complete system assets. And the beam reporting is UE reporting the proper beam, which it has selected for its transmission back into the gNodeB. So that's the process of beam reporting.

And beam recovery is, again, another interesting process when we think about the beam failures. In case if there is any failures, it's something similar to the radio link failure reporting in the higher layers. Beam failure is, again, failure of that specific beam which is used for transmission. And then in that case, beam switching has to happen. That is switching from one beam to another.

Since all these things happened in the physical and the mag layer coordination itself, the communication to the higher layers are wider, and hence these things are much faster, when compared to the handovers in the LTE where we need to think about moving-- I mean commanding until the MME or until core network replies.

Basically, it defines a set of procedures for the beam management. That is, again, based out of 38.802. The procedure one speaks about the initial acquisition-based procedure which is, again, based on the synchronization signal block. This is based on the RSRP, received signal reference power measurements, and this is basically done in the idle mode. And so that's like whenever a UE have to switch on and get connected to the gNodeB so it does the procedure one in order to acquire a coarser beam, which is of a good strength for it to connect to.

The next one is on the final beam refinement that is spoken in procedure two and procedure three. Procedure two deals with the transmitter and beam refinement and it's basically happening in the connected mode of the UE state. And it basically uses the non-zero power CSI-RS resource in the downlink and SRS in the uplink.

Procedure three is synonymous to procedure two, which is actually a receive-end beam adjustment. And that's, again, done on the connector. What the overall idea here is get a broader beam using procedure one. And once you are connected to the gNodeB then within that broader beam, tune to a more finer beam which can be used-- which is actually best beam for you to work on and which can be used for your further communications. That's the ultimate idea.

And the standalone operation flow is something like this. gNodeB basically transmits the excess burst whenever UE is switching on for the first time, or whenever it moves from an idle mode. It's waking up, so it sends for the burst and it finds the best burst and the best signal using the received power. It sweeps it and measures the signal and it determines which beam it has to use.

And then once it determines, it reports back the beam to gNodeB using the RACH preamble using the same precoding vector which is used for the SSB. So that is a one-to-one mapping between the code used and the code which is sent in the RACH preamble, which will make gNodeB understand that the beam, which the UE is using-- the UE has selected.

And again, you'll be able to do a beam sweeping or the beam management-based simulation easily using the MATLAB 5G Toolbox, another environment. So we start with the SS burst generation. We do beam sweeping. This is basically an analog beamforming which is done for procedure one that is done after the OFDM modulation, whereas in the procedure two, three where we do finer beam refinement. We work on the digital beamforming. Once the beamforming is done, we add the channel noise. And then the receiver side, again, we do the receiver operations such as beam sweeping, timing synchronization, OFDM demodulation.

So with that, we come to this summary part of today's discussion. The idea here is to showcase you that you'll be able to do an end-to-end baseband RF phased array antenna simulation easily for the 5G beamforming-based architecture, both on the transmitter and receiver side with adding channel modules. The GUI-based applications which we saw today will really help you to easily design the system and understand the system in detail. But also finally MATLAB and Simulink access and multi-domain engineering platform to design the RF antenna baseband, everything together in a single platform.

So I have a summary of various Toolboxes, which would be helpful for you to make your end-to-end workflow possible. For example, on the baseband side, all these standards are supported like the satcom communications, satellite communications, 5G, LTE, WLAN, Bluetooth, Zigbee, Wi-Fi, ultra-wideband. And again on the RF side, you'll be able to design your complete RF antenna system then plug it to the other baseband and then simulate an end-to-end system.

This slide gives a summary of various toolboxes which are offered. And again, the good part is you'll also be able to do an over the air testing using SDR and various RF instruments. So if you have a software-defined radio, maybe an RTL or a Zynq SDR, or an RFSoC, you'll be able to directly connected to MATLAB and then do a transmission for the signal directly from there to MATLAB.

And then the receiver side, again, you'll be able to capture that signal and then take it back into the MATLAB environment and use it further. That is, again, possible with the RF instruments. If you have a signal generating and signal capturing instrument, you will be able to directly do that from that as well.

We have nice white papers on the hybrid beamforming for massive MIMO and phased array systems. We also have another white paper on understanding the 5G beam management. This is very much relevant to today's talk. So if you are interested in any of those, feel free to have a look and get back to us for any questions, any thoughts, and any suggestions, or any help in any of the areas which you are working on in building your 5G-based massive MIMO hybrid beamforming feature.