>But compared to how we use our phones today, what new items will be be able to do with 5G that we can't do with current 4G/LTE?
5G has the potential to provide throughput and latency that is comparable to a fixed broadband connection. In reasonably competitive markets (i.e. not the US), that's A Big Deal. Latency is a particularly acute issue in many applications; 4G generally adds about 50ms in the best case scenario, but 5G can easily provide sub-millisecond latency. Imagine a near-future where it simply doesn't matter whether you're on WiFi or cellular, because they both provide the same experience.
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Is the sub-millisecond from repeater to repeater or from origin to final destination that's [n] repeaters away? Won't each repeater introduce its own latency?
One thing is that 4G is generally centrally broken out to the internet.
So let's say you're in Scotland, the packet would enter the mobile operator's network, then go to London, where they've bridged the network to the internet.
5G non stand alone can provide this due to the new core network. But we are still at the mercy of the speed of light. A round trip of 1 millisecond translates to about 150 km (95 miles) of distance between you and your resource. And that is without any signal processing at the receiving end and in the air to fiber interface.
From my current location, it's a 13ms round-trip to the nearest Google server via a good fixed broadband connection; over 4G, that would be ~63ms because of the latency overhead of the cellular connection. That's a substantial difference for a lot of real-time applications.
I do not deny that 4G has worse latency, but 5G will not provide sub millisecond round trip latency for regular internet based applications. Sub millisecond latencies are due to local communication which can replace DSRC/802.11p in car2car communication and similar applications.
5G has the potential to provide throughput and latency that is comparable to a fixed broadband connection. In reasonably competitive markets (i.e. not the US), that's A Big Deal. Latency is a particularly acute issue in many applications; 4G generally adds about 50ms in the best case scenario, but 5G can easily provide sub-millisecond latency. Imagine a near-future where it simply doesn't matter whether you're on WiFi or cellular, because they both provide the same experience.