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Hi, I am Mike Wohlert, business development engineer at Agilent Technologies. This is
the second in a series of three LTE-Advanced carrier aggregation demonstrations using Agilent's
new UXM wireless test set. For this demo, our applications engineer, Colin Urquhart,
is here to show you the downlink channel configuration flexibility for LTE receiver testing. He will
also show you the impact of these configurations on throughput. As in the other videos in the
series, the demo setup uses a commercial LTE-Advanced category 4 device. Over to you, Colin. Thanks,
Mike. LTE networks are designed to be able to adapt to a wide range of real world operating
conditions. Depending on the quality of the downlink channel, the eNodeB will adjust the
modulation type, coding schemes, and resource block allocations to optimize to the best
performance. This results in thousands of potential scenarios under which the mobile
device may need to perform. Making sure your design can deal with all these combinations
is no easy task. That is why we developed the UXM for the most flexible and easy-to-use
LTE downward channel configuration in the industry. Let's start the demonstration with
the UXM's bler vs. time measurement. As you saw in the first video, this category 4 device
achieves 145 Mbps downlink, and 25 Mbps uplink. Let's view the standard RMC configuration,
and I will show you how you can easily configure the downlink channel. By selecting these parameters,
I am able to set the modulation schemes for all the subframes and for both code words
all at once. I will drop the modulation coding scheme from 28 to 24. You can see the throughput
drop on the measurement trace as expected. Now, I will set only one code word at a time.
For all subframes, I will select 18 and apply that to code word 2. Again, there's a further
drop in throughput, as expected. For even more flexibility, you can disable "configure
all subframes at once," and set the modulation coding scheme for each subframe individually
and for each code word. As you modify these settings, you can also view the data throughput
on the fly. Now that we have seen the flexibility in setting modulation coding schemes, let's
look at the resource block allocations. This interface provides the configuration options
to allocate consecutive subframes or all the subframes at once, and also noncontiguous
allocations. I will reduce the number of resource blocks by arbitrarily selecting just a few.
Again, throughput has dropped as expected because of the reduced allocation. As you
can see, with this large touch interface, it is very simple to configure different scenarios.
Back to you, Mike. Thank you, Colin. We just saw the extreme flexibility the UXM provides
in LTE downlink channel configuration and resource block allocations. This enables you
to quickly and easily validate device performance under a wide range of operating conditions.
With the UXM you can assess your design readiness with greater confidence. Is your design ready?
For more information, visit the website on your screen. Thank you for watching.