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<v Speaker 1>You know, it's pretty wild when you stop and think

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<v Speaker 1>about it. Every time you make a call or send

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<v Speaker 1>a text, you can just load a webpage. Your phone

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<v Speaker 1>is talking this like secret language, tapping into this massive

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<v Speaker 1>invisible network, towers, other devices. It's all happening constantly without

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<v Speaker 1>you really noticing the nuts and bolts. Welcome to the

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<v Speaker 1>deep dive today. We're going to try and unravel that

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<v Speaker 1>hidden language. We're tracing the whole evolution of mobile networks,

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<v Speaker 1>you know, from those first crackly digital calls, all the

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<v Speaker 1>way up to super fast five G, and we'll even

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<v Speaker 1>touch on Wi Fi and Bluetooth, the local stuff. Our

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<v Speaker 1>mission really is to pull out the key insights from

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<v Speaker 1>some expert sources. We've got this great text that maps

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<v Speaker 1>the journey gsm U, MTS, LTE, five G, double Land, Bluetooth.

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<v Speaker 1>The idea is to give you a shortcut, help you

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<v Speaker 1>get how this connected world ticks without drowning and text speak.

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<v Speaker 1>It's a huge leap bran from just voice to all

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<v Speaker 1>this complex data streaming around. And there are some genuinely

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<v Speaker 1>surprising bits of tech inside your phone you might not

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<v Speaker 1>even know about.

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<v Speaker 2>Absolutely, And what I find fascinating is how each general, Well,

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<v Speaker 2>it builds on the one before. It's often solving problems

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<v Speaker 2>you didn't even realize were problems. It really is like

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<v Speaker 2>a symphony of engineering just to keep us all talking, texting, streaming, connected.

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<v Speaker 3>Okay, let's rewind way back GSM two g before smartphones

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<v Speaker 3>really took off. Yeah, how did your voice actually, you know,

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<v Speaker 3>travel wirelessly to someone else? I seems basic.

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<v Speaker 2>Now, but back then it was revolutionary. Really, GSM set

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<v Speaker 2>the stage for digital mobile comms. You had a few

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<v Speaker 2>core components. The Mobile Switching Center the MSSE. Think of

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<v Speaker 2>it as the brain, handling call routing, knowing where you were,

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<v Speaker 2>and it worked with the Home Location Register the HLR.

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<v Speaker 2>That's basically the big database holding your subscriber info, your

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<v Speaker 2>number services.

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<v Speaker 3>Okay, so the network knows who you are and where

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<v Speaker 3>you are roughly, but getting the voice signal itself over

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<v Speaker 3>the airwaves that limited resource. How did they squeeze it

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<v Speaker 3>in efficiently? This is where it gets really clever.

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<v Speaker 2>I think you're right. That's where the transcoding and rate

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<v Speaker 2>adaptation you died, the TRAU came in. It was a

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<v Speaker 2>critical piece. See inside the main network, your digitized voice

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<v Speaker 2>used something called PCM took up about sixty four kilobits

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<v Speaker 2>per second, pretty chunky. The tierrau's job was to compress

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<v Speaker 2>that like, squash it down in real time, often to

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<v Speaker 2>around thirteen kilobits per second for the radio part. Imagine yeah,

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<v Speaker 2>a big truck of data and needing to get through

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<v Speaker 2>a narrow tunnel. The TREU made it fit. It meant

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<v Speaker 2>more people could share the same limited airwaves, and that

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<v Speaker 2>compression technology kept improving. GSM introduced AMR Adaptive Multi Rate

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<v Speaker 2>Codex and then AMR Wideband or AMRWB. This was huge

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<v Speaker 2>for quality. AMRWB digitized a much wider frequency range, up

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<v Speaker 2>to seven thousand hertz compared to like thirty four hundred

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<v Speaker 2>hertz before. Suddenly voices sounded much richer, more natural, less

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<v Speaker 2>telephony if you know what I.

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<v Speaker 3>Mean, definitely. So voice was sorted getting more efficient, sounding better.

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<v Speaker 3>But then came the desire for data. Remember the WAP

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<v Speaker 3>that's super slow early mobile Internet. What was the hurdle

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<v Speaker 3>there and how did TPRs two point five g.

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<v Speaker 1>Tackle it right?

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<v Speaker 2>GPRS it was essentially the packet's switched add on to

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<v Speaker 2>the circuit switched voice network. It used a different node

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<v Speaker 2>the serving GPRS support node SGSN. The key difference was

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<v Speaker 2>how it used the air interface. GSM Voice gave you

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<v Speaker 2>a dedicated channel, a traffic channel for your whole call,

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<v Speaker 2>even during silence. GPRS introduced the Packet Data Traffic Channel PDTCCH.

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<v Speaker 2>This could be shared. Your phone only used a timeslot

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<v Speaker 2>when it actually had data packets to send or receive.

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<v Speaker 2>Much more efficient for that bursty web browsing or sending

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<v Speaker 2>an early MMS and.

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<v Speaker 3>Moving around or getting an incoming call. There were protocols

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<v Speaker 3>coordinating all that behind the scenes, right exactly.

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<v Speaker 2>The Mobile Application Part or MAP protocol was key for that.

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<v Speaker 2>It let the network like the ms E equery of the

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<v Speaker 2>HLR to find out which tower you were currently near.

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<v Speaker 2>That's how calls found you. And underneath MAP you had

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<v Speaker 2>Signaling System number seven S seven protocols. These came from

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<v Speaker 2>the fixed line world but were adapted for mobile over time.

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<v Speaker 2>They even started running the lower layers over IP and Ethernet.

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<v Speaker 2>More modern, more flexible.

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<v Speaker 3>Okay, fast forward a bit too. Thousands umts, the third

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<v Speaker 3>generation three G. This is where mobile data started to

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<v Speaker 3>feel well usable. What was the big technical shift?

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<v Speaker 2>The fundamental change with UMTS was the move to code

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<v Speaker 2>division multiple access CDMA. Instead of slicing up time or

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<v Speaker 2>frequency like GSM did, CDMA lets everyone share the same

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<v Speaker 2>frequency band at the same time. Users are separated by

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<v Speaker 2>unique mathematical codes spreading codes. The radio network changed too,

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<v Speaker 2>It was called you Dream. It had nodeBs, which are

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<v Speaker 2>like the base stations and radione or controllers RNCs managing

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<v Speaker 2>groups of nodeBs, and your phone became user equipment or UE.

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<v Speaker 3>Huh So if everyone's using the same frequency, doesn't that

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<v Speaker 3>cause like interference? How does that work?

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<v Speaker 2>That's a great point, and yes it does. It leads

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<v Speaker 2>to this really interesting effect called cell breathing, because everyone's

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<v Speaker 2>signal is technically interference to everyone else in that cell.

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<v Speaker 2>As more people join, the overall interference level goes up

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<v Speaker 2>to cope. Phones and the NodeB have to transmit with

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<v Speaker 2>more power to be heard over the noise and the

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<v Speaker 2>The side effect of needing more power is that the

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<v Speaker 2>maximum reliable distance shrinks, so the cell's coverage area literally

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<v Speaker 2>contracts when it's busy and expands when it's quiet.

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<v Speaker 1>It breathes.

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<v Speaker 3>Wow, okay, cell breathing. That's not something you'd intuitively think about.

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<v Speaker 3>So building on that, things got faster again with HSDPA

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<v Speaker 3>and HSPA plus. Buy that felt like a real speed boost.

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<v Speaker 3>What was the secret sauce there?

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<v Speaker 2>Yeah, HSDPA High Speed Downlink Packet Access was a big

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<v Speaker 2>step up for speed. One key thing was moving away

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<v Speaker 2>from dedicated channels just for you to using shared channels

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<v Speaker 2>the hfdsch and importantly, the scheduling deciding who gets to

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<v Speaker 2>transmit when moved closer to the user down to the

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<v Speaker 2>node b this myth the network could react much faster

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<v Speaker 2>to changing radio conditions, allocating resources more efficiently. That pushed

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<v Speaker 2>speeds up significantly. HSTPA got you maybe fourteen megabits per second,

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<v Speaker 2>ideally HSPA plus went even further over thirty. That's when

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<v Speaker 2>mobile web browsing really started to feel okay. They also

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<v Speaker 2>introduced things like continuous packet connectivity cpclater on to try

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<v Speaker 2>and reduce battery drain during those gaps when you weren't

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<v Speaker 2>actively transmitting data but wanted to get back online quickly.

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<v Speaker 3>Right, battery life is always a concern, so the phone

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<v Speaker 3>wasn't just always on full blast.

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<v Speaker 1>It had different modes exactly.

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<v Speaker 2>UMTS defined Radio Resource Control RC states if you were

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<v Speaker 2>actively streaming or on a call, you'd be in a

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<v Speaker 2>state like cell DCCH with dedicated resources high power, but

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<v Speaker 2>for smaller bursty things checking email background updates, you might

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<v Speaker 2>be in sell AVCH using shared resources lower power. The

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<v Speaker 2>network couldn't guarantee a data rate or delay in FACCH,

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<v Speaker 2>kind of like best effort ethernet, but it saved a

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<v Speaker 2>lot of battery. It's always a trade off. And one

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<v Speaker 2>more clever thing in UMTS mobility was soft handover. Remember

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<v Speaker 2>how in GSM you'd kind of drop one tower just

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<v Speaker 2>before picking up the next. With soft handover, your phone

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<v Speaker 2>could actually be connected to multiple nodeBs simultaneously for a

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<v Speaker 2>brief period during the transition. It made handovers much smoother

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<v Speaker 2>or fewer dropped calls, especially as you move between cells

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<v Speaker 2>controlled by different R and CS that could coordinate via

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<v Speaker 2>an interface.

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<v Speaker 3>Call ir okay onto LTE four G. This really changed everything,

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<v Speaker 3>didn't it. Streaming HD video on your phone became normal.

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<v Speaker 3>What was the absolute biggest shift.

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<v Speaker 2>With LTE The philosophy changed completely. LTE was designed from

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<v Speaker 2>the ground up as a pure IP network that circuit

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<v Speaker 2>switched rests. Stuff from GSM and u MTS gone. It

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<v Speaker 2>was all data packets now, voice itself just became another

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<v Speaker 2>application running over the IP data network, and the core

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<v Speaker 2>network got flatter, fewer different kinds of boxes, which helped

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<v Speaker 2>reduce latency that delay. You sometimes notice it made everything snappier.

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<v Speaker 3>Wait, hold on, if circuit switching is gone, how do

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<v Speaker 3>you make a normal phone call? Isn't that still essential?

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<v Speaker 2>Good question? That's handled by volty voiceover LTE. It uses

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<v Speaker 2>a framework called the IMS, the IP Multimedia Subsystem to

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<v Speaker 2>manage voice calls as IP data streams. Crucially, VOLTI gets

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<v Speaker 2>special treatment. It uses dedicated bearers in the network. That

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<v Speaker 2>means the network guarantees quality of service, low latency, consistent

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<v Speaker 2>bandwidth essential for a good call quality, and they even

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<v Speaker 2>use unacknowledged mode data radio bears UMDRB for voice packets.

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<v Speaker 2>The idea is if a tiny bit of voice data

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<v Speaker 2>gets lost, it's better to just keep going rather than

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<v Speaker 2>retransmitting it late, which would just sound garbled anyway. Plus

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<v Speaker 2>SRVCC single radio Voice call continuity handles the handover if

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<v Speaker 2>you move out of four G coverage mid call, dropping

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<v Speaker 2>you back to three G or two G voice without

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<v Speaker 2>losing the call.

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<v Speaker 3>Okay, that makes sense. So the speed ltefl fast What

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<v Speaker 3>were the key radio technologies making that happen, Things like

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<v Speaker 3>OFDM and.

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<v Speaker 2>MIMO exactly OFDM. Orthogonal frequency division multiplexing is quite clever.

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<v Speaker 2>Instead of using one wide radio channel, it splits it

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<v Speaker 2>into hundreds, sometimes thousands, of very narrow subcarriers, all orthogonal,

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<v Speaker 2>meaning they don't interfere with each other. Think of it

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<v Speaker 2>like having many small parallel pipes instead of one big one.

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<v Speaker 2>It makes the signal much more robust against things like

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<v Speaker 2>echos or reflections. And then MIM multiple input multiple output.

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<v Speaker 2>This is huge. Uses multiple antennas on the base station

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<v Speaker 2>and on your phone to send multiple data streams at

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<v Speaker 2>the same time over the same frequency band. If you

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<v Speaker 2>have say two antennas two by two MIMO, you can

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<v Speaker 2>potentially double your data rate. Four antennas four by four

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<v Speaker 2>MIMO potentially quadruple it. It's a massive capacity booster.

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<v Speaker 3>And for the really high speeds, didn't they start gluing

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<v Speaker 3>different frequency bands together like creating wire highways precisely?

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<v Speaker 2>That's carrier aggregation or CAA. An operator might have licenses

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<v Speaker 2>for spectrum in different bands. CAA lets them combine several

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<v Speaker 2>of these carriers, maybe up to twenty miliherds each into

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<v Speaker 2>one logical wider channel for your phone, so instead of

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<v Speaker 2>just a twenty milliahurtz channel, you might get forty sixty

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<v Speaker 2>or even more, directly increasing your potential peak speed. It's

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<v Speaker 2>more common and powerful for downloads, though uplink CA is

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<v Speaker 2>trickier because your phone's battery and power output are limiting factors.

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<v Speaker 3>Makes sense now, Battery life again always crucial. How did

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<v Speaker 3>LTE improve things there? Especially for all those connected devices

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<v Speaker 3>popping up the Internet of Things?

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<v Speaker 2>LTE brought in more sophisticated power saving. When your phone

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<v Speaker 2>is connected but not actively transferring data, it can use

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<v Speaker 2>discontinuous reception DRX. It basically agrees with the network to

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<v Speaker 2>switch off its radio receiver for short periods and only

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<v Speaker 2>wake up at specific intervals to check if there's data waiting.

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<v Speaker 2>And for those IoT devices that only need to send

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<v Speaker 2>tiny bits of data very infrequently, think sensors meters, LTE

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<v Speaker 2>introduced Power Save Mode PSM and Extended Idle Mode DRX EDRX.

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<v Speaker 2>These let devices go into a really deep sleep, powering

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<v Speaker 2>down their radio almost completely for potentially hours, days, even weeks,

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<v Speaker 2>and only waking up periodically. Huge battery savings for those

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<v Speaker 2>use cases. And another efficiency booster, particularly for volty and

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<v Speaker 2>those loaded IoT devices, is robust header compression OHC. IP packets,

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<v Speaker 2>especially with UDP and rtpus for voice, have quite large

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<v Speaker 2>headers relative to the actual voice data. ROHC compresses these headers,

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<v Speaker 2>significantly reducing the amount of data sent over the air.

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<v Speaker 2>Every bit saved helps with battery and network capacity.

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<v Speaker 3>And moving between network types, like if you drive from

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<v Speaker 3>a four G area into a three G only zone,

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<v Speaker 3>how did LTE handle that gracefully?

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<v Speaker 2>LTE was designed for smooth interconnection with UMTS and GSM.

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<v Speaker 2>Your phone performs procedures like location area updates or routing

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<v Speaker 2>area updates when it moves between network types. The core

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<v Speaker 2>network nodes, the MME and LTE and the SGSN and

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<v Speaker 2>two G three G can exchange your subscriber context information.

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<v Speaker 2>This ensures your ongoing data session or call can be

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<v Speaker 2>maintained seamlessly as you switch technologies. It's designed to be

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<v Speaker 2>pretty invisible to you, and it's worth mentioning. The hardware

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<v Speaker 2>shift to the core network equipment itself changed. We moved

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<v Speaker 2>away from expensive proprietary boxes towards using more standardized Intel

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<v Speaker 2>by eighty six, servers. Combined with concepts like network function

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<v Speaker 2>Virtualization NFV and later cloud native principles, especially heading towards

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<v Speaker 2>five G, it gave operators much more flexibility, scalability, and

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<v Speaker 2>often lower costs. They could spin up network functions like

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<v Speaker 2>software on standard.

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<v Speaker 3>Hardware right which brings us to now five G. We

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<v Speaker 3>hear about it constantly, beyond just being fit aster four G.

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<v Speaker 3>What's fundamentally new? We're different about five G.

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<v Speaker 2>New radio five G does bring several genuinely new things.

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<v Speaker 2>One big one is the expansion into new frequency bands.

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<v Speaker 2>We have frequency range one FR one, which is below

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<v Speaker 2>six gigaherts, similar bands to four G, but five G

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<v Speaker 2>can use wider channels within them up to one hundred

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<v Speaker 2>minie herts. But then there's frequency range two FR two

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<v Speaker 2>to the millimeter mill wave bands. These are much higher

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<v Speaker 2>frequencies like twenty four gigaherts and above. The huge advantage

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<v Speaker 2>of millimwave is massive available band with carriers up to

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<v Speaker 2>four hundred milliherts wide. This enables those multi gigabit speeds

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<v Speaker 2>you hear about the downside physics, Those high frequencies don't

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<v Speaker 2>travel for maybe tens or hundreds of meters and they're

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<v Speaker 2>easily blocked by walls, even leaves on trees. So millimwave

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<v Speaker 2>is great for specific hotspots stadiums, busy streets, airports, but

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<v Speaker 2>not for wide area coverage.

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<v Speaker 3>Okay, so different frequencies for different scenarios. Yeah, but deploying this,

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<v Speaker 3>how do operators manage putting five G in places that

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<v Speaker 3>already have four G without needing double the antennas and

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<v Speaker 3>spectrum everywhere.

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<v Speaker 2>That's a key challenge, and the answer is dynamic spectrum

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<v Speaker 2>sharing DSS. DSS is a clever software feature that allows

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<v Speaker 2>a base station to transmit both fur GLTE and five

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<v Speaker 2>GNR signals in the same frequency band at the same time.

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<v Speaker 2>It dynamically allocates the time and frequency resources within that

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<v Speaker 2>band between four G and five D users based on

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<v Speaker 2>demand millisecond by millisecond, so an operator can upgrade a

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<v Speaker 2>site to support five G using their existing four G

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<v Speaker 2>spectrum and serve both types of users efficiently. As the

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<v Speaker 2>number of five G devices grows, it smooths the transition massively.

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<v Speaker 2>And five G isn't just about the radio. There's the

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<v Speaker 2>option of a completely new core network architecture called five

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<v Speaker 2>G Standalone SSA. This introduces new more modular core network functions,

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<v Speaker 2>things like the access management function AMF for handling connections

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<v Speaker 2>and mobility, the session management function SMF for managing your

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<v Speaker 2>data sessions, and the user plane function UPF, which actually

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<v Speaker 2>forwards your data packets. This service based architecture is designed

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<v Speaker 2>to be cloud native, more flexible, and enables advanced features

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<v Speaker 2>like network slicing.

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<v Speaker 3>So it sounds like the brain of the network out

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<v Speaker 3>a major overhaul two, more flexible, more software driven.

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<v Speaker 2>Exactly the five G core network procedures for things like registration,

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<v Speaker 2>connection management, session establishment, mobility. They're all redesigned to be

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<v Speaker 2>more granular and suited for this virtualized cloud environment. And

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<v Speaker 2>for mobility between five G based stations called GMB's. There's

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<v Speaker 2>the XN interface, which is analogous to the X two

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<v Speaker 2>interface and LTE, allowing fast handovers directly between base stations

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<v Speaker 2>without always involving the core network. Security also gets a

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<v Speaker 2>boost in five G. For instance, when your phone first connects,

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<v Speaker 2>it can use a subscription concealed Identifier SUCI instead of

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<v Speaker 2>sending your permanent identifier MSI in the clear. This helps

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<v Speaker 2>protect your privacy against tracking and the main authentication process

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<v Speaker 2>verifying you are who you say you are is anchored

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<v Speaker 2>more strongly in your home network, making things more secure,

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<v Speaker 2>especially when roaming.

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<v Speaker 3>Okay, let's step away from the big cellular networks for

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<v Speaker 3>a moment. Our devices also rely hugely on local wireless

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<v Speaker 3>tech Wi Fi and Bluetooth. What makes the tick and

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<v Speaker 3>how do they fit into the picture?

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<v Speaker 2>Right? Wi Fi or technically w Lan based on IE

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<v Speaker 2>eight to two point one one standards, it comes in

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<v Speaker 2>a few flavors. You'd have ad hoc mode, where devices

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<v Speaker 2>connect directly peer to peer, not super common for most users.

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<v Speaker 2>Much more typical is a basic service set BSS. That's

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<v Speaker 2>your home Wi Fi router, the access point or AP,

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<v Speaker 2>and the device is connected to it. Than in larger

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<v Speaker 2>places like offices or campuses, you have an extended service

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<v Speaker 2>set ESS, which is multiple aps connected together, usually by wires,

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<v Speaker 2>appearing as a single network so you can roam seamlessly.

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<v Speaker 3>Got it now that crowded coffee shop scenario wi Fi

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<v Speaker 3>slows down? You mentioned interference before with cdma's or something

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<v Speaker 3>similar in Wi Fi.

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<v Speaker 2>Yes, absolutely, Wi Fi uses a shared medium, the airwaves.

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<v Speaker 2>A classic problem is the hidden station problem. Imagine you

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<v Speaker 2>and someone else are both connected to the same Wi

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<v Speaker 2>Fi hotspot, but you're too far apart to hear each

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<v Speaker 2>other directly. If you both try to transmit to the

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<v Speaker 2>access point at the same time, your signals collide at

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<v Speaker 2>the AP and neither gets through cleanly. To help with

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<v Speaker 2>Wi Fi has an optional mechanism called RTSCTS Ready to

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<v Speaker 2>Send Clear to Send. A device can send an RTS request.

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<v Speaker 2>The AP broadcasts the CTS message, telling everyone else to

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<v Speaker 2>be quiet for a bit. It reserves the air, helps

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<v Speaker 2>avoid collisions, but adds overheads, so it can reduce overall throughputs.

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<v Speaker 3>And Wi Fi keeps getting smarter too. Writ Newer versions

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<v Speaker 3>like Wi Fi five and six use beam forming. How

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<v Speaker 3>does that work? Sounds like Sci Fi?

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<v Speaker 2>It's pretty neat. Instead of the access point just blasting

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<v Speaker 2>the signal out equally in all directions, beamforming tries to

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<v Speaker 2>focus the transmission towards where your device actually is. The

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<v Speaker 2>AP sends out a sounding packet, Your device measures how

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<v Speaker 2>that signal arrived, and sends back feedback. Using that feedback,

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<v Speaker 2>the AP calculates how to adjust the signals from its

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<v Speaker 2>multiple antennas so they combine constructively at your device's location.

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<v Speaker 2>It results in a stronger signal for you better speeds

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<v Speaker 2>and potentially less interferance for others.

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<v Speaker 3>Cool. Okay, last one. Bluetooth headphones, speakers, smart watches connects

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<v Speaker 3>everything nearby. How does it juggle all those connections without

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<v Speaker 3>turning into gear chaos?

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<v Speaker 2>Bluetooth uses small personal networks called pecanets. One device is

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<v Speaker 2>the master, like your phone, and it can talk to

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<v Speaker 2>up to seven active slave devices like headphones, a keyboard,

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<v Speaker 2>et cetera. To let lots of these picanetes operate in

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<v Speaker 2>the same space, like in an office or on a bus.

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<v Speaker 2>Bluetooth uses adaptive frequency hopping AFH. It rapidly hops between

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<v Speaker 2>dozens of different channels and the two point four giblhertz

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<v Speaker 2>band following a pseudorandom sequence. But crucially it's adaptive. It

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<v Speaker 2>learns which channels are noisy or occupied, maybe by Wi

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<v Speaker 2>Fi or other Bluetooth devices, and avoids them.

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<v Speaker 3>And the battery life on Bluetooth devices is often amazing.

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<v Speaker 3>How does it manage that?

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<v Speaker 2>Power saving is baked into Bluetooth Devices can agree to

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<v Speaker 2>enter low power states like sniff or hold. In sniff mode,

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<v Speaker 2>a slave device only wakes up to listen for packets

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<v Speaker 2>from the master at pre agreed intervals, maybe every few

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<v Speaker 2>hundred milliseconds, instead of listening constantly. Hold mode lets a

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<v Speaker 2>device power down its transceiver completely for a set period.

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<v Speaker 2>These drastically cut down power can some when there's no

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<v Speaker 2>active data transfer. And then there's Bluetooth Low Energy Ble,

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<v Speaker 2>which is a whole different flavor, really optimized for ultra

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<v Speaker 2>low power. It's designed for things like sensors, fitness trackers,

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<v Speaker 2>smart home gadgets that only need to exchange small amounts

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<v Speaker 2>of data very occasionally. It uses a different way of

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<v Speaker 2>communicating based on reading and writing attributes or variables using

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<v Speaker 2>protocols called att and gay ett. Very efficient for those

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<v Speaker 2>simple sense status update type tasks hashtag tag outro Wow.

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<v Speaker 1>Okay.

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<v Speaker 3>So from these globe spanning cellular networks that have evolved

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<v Speaker 3>generation by generation right down to the personal bubble of

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<v Speaker 3>connectivity around us with Wi Fi and Bluetooth, it's just

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<v Speaker 3>incredible the sheer amount of engineering and constant innovation that

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<v Speaker 3>makes it all work so seamlessly most of the time.

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<v Speaker 3>It really is like a hidden language our devices are

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<v Speaker 3>speaking constantly.

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<v Speaker 2>It absolutely is, and it makes you wonder, doesn't it.

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<v Speaker 2>As these different networks cellular Wi Fi, maybe even others

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<v Speaker 2>become even more tightly integrated, smarter. How will that change

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<v Speaker 2>how we think about being connected? What does that seamless

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<v Speaker 2>handoff between different kinds of networks mean for our daily lives,

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<v Speaker 2>for future applications we haven't even conceived of yet.

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<v Speaker 3>That's a great thought to end on. So the next

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<v Speaker 3>time you pull out your phone, maybe take just a

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<v Speaker 3>second to appreciate that silent, incredibly complex dance as signals

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<v Speaker 3>happening all around you. What part of this journey through

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<v Speaker 3>mobile networks surprised you the most? We hope this deep

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<v Speaker 3>dies gave you some new insights into the invisible world

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<v Speaker 3>keeping us all connected.