3 ms·

Looks like the move from 3G to 4G also meant going from "real speeds are 1/5th of theoretical max" to "real speeds are 1/10th of theoretical max". I wonder if t

by m12k 5y ago

Looks like the move from 3G to 4G also meant going from "real speeds are 1/5th of theoretical max" to "real speeds are 1/10th of theoretical max". I wonder if that's due to congestion at the phone-to-tower level, congestion at the tower-to-internet level, or due to newer wireless tech just having higher peak performance at optimal physical conditions (e.g. line of sight) that are becoming increasingly hard to actually accomplish in practice?

timeinput 5y ago
I think the primary driver is higher peak performance. With OFDM on 4G and 5G you can have very wide bandwidths for a given tower, and small, but high QoS allocations for voice, or high bandwidth for video streaming. With 3G you had similar flexibility, but the peak RF bandwidth was ~3.84 MHz compared to ~40 MHz of 4G). This is doubly so with 5G. The maximum allocation is potentially huge from a time and (RF) bandwidth point of view, but an HD video stream is still limited.
mytailorisrich 5y ago
The aim is also to increase capacity because of the ever increasing number of mobile devices. Increasing capacity means increasing the number of devices that may connect to a single base station (aka "tower") at any given time. This was true when moving from 3G to 4G, and this is also true when moving from 4G to 5G, though with 5G there is an emphasis on a very large number of devices with relatively low data rates (in order to accommodate IOT scenarios).
cptskippy 5y ago
> I wonder if that's due to congestion at the phone-to-tower level, congestion at the tower-to-internet level, or due to newer wireless tech just having higher peak performance at optimal physical conditions (e.g. line of sight) that are becoming increasingly hard to actually accomplish in practice? I believe this is entirely configurable by the carrier. As others have pointed out, the primary driver of each successive generation is to support more clients. Increasing individual client bandwidth is a secondary motivation.

by m12k 5y ago

timeinput 5y ago

I think the primary driver is higher peak performance. With OFDM on 4G and 5G you can have very wide bandwidths for a given tower, and small, but high QoS allocations for voice, or high bandwidth for video streaming. With 3G you had similar flexibility, but the peak RF bandwidth was ~3.84 MHz compared to ~40 MHz of 4G). This is doubly so with 5G. The maximum allocation is potentially huge from a time and (RF) bandwidth point of view, but an HD video stream is still limited.

mytailorisrich 5y ago

The aim is also to increase capacity because of the ever increasing number of mobile devices. Increasing capacity means increasing the number of devices that may connect to a single base station (aka "tower") at any given time. This was true when moving from 3G to 4G, and this is also true when moving from 4G to 5G, though with 5G there is an emphasis on a very large number of devices with relatively low data rates (in order to accommodate IOT scenarios).

cptskippy 5y ago

> I wonder if that's due to congestion at the phone-to-tower level, congestion at the tower-to-internet level, or due to newer wireless tech just having higher peak performance at optimal physical conditions (e.g. line of sight) that are becoming increasingly hard to actually accomplish in practice? I believe this is entirely configurable by the carrier. As others have pointed out, the primary driver of each successive generation is to support more clients. Increasing individual client bandwidth is a secondary motivation.