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5G spectrum is not limited to high frequencies.

5G spectrum goes from high-bands 24-40 Ghz, mid-bands 1-6Ghz, and low bands < 1 Ghz




But aren't those hz bands limited in their throughput to about where 4g is?


increased synchronization between stations should allow for better beamforming to go along with the positional information, increasing throughput somewhat in the face of interference/attenuation


IIRC there is also a lot of improvement in channel multiplexing both at raw physical layer and link layers to allow e.g. numerous IoT type devices to have a low-rate cell connection without a plan.


This also allows packets to start at more times, which means that latency can decrease. (aka, lower ping times.)


Ah so a more robust and reliable, multi station system is formed? What's this beam forming and positional information stuff? Are they tailoring signals to individaul devices? That's so cool! This stuff is starting to feel like electro magnetic magic, haha.


yeah- they call it time-domain-multiplex (or something) when you have different phones subscribing to listen at different points in time. Traditionally only the closest station would broadcast to each phone, because multiple stations broadcasting the same frequency leads to a mushy signal (on average). BUT, if all the stations are synced, they can align the phases of their signals so that they 'constructively interfere' into a brighter signal where the target phone is. The appropriate phase difference will be different for each phone, so each time slice signal is indeed tailored to each device-- they also need to track device movement, to best target the signal while it drives/walks around.

'beamforming' is a kind of confusing term, based on how a bunch of antennas in a tight group can time their phases into a cone of signal-- functionally aiming the antenna, but without anything physically moving. When the involved antennas are not in a tight group, the 'beam' that is formed starts to look less like a cone, and more like a target 'bean'... beanforming ....

anyway this demo page can show some of how it works, ui is kind of weird, type a number and click to add/move an antenna, hit 'r' and click to place the receiving device, 'o' to align the phases for best signal.. https://apenwarr.ca/beamlab/




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