[Ballu]

Then you are not getting 5G. In FR1 (sub 6GHz), we are not going to get much advantage. In the end, there is a limit of data you can send per Hz. This is not increasing from 4G to 5G (yes, you can use higher coding mechanism, but that's only for short distance, otherwise noise impact negates all advantages). To get the higher bandwidth as predicted and expected, industry has to move to FR2 (24GHz+/mmWave, I don't want to go into the discussions that mmWave starts at later band, the difference is statistical error). To support mmWave, standards bodies defined new standards/adopted technologies like beam forming, higher matrix antennas etc. And thats really a difference in 5G from 4G standards releases (along with cloud native core network with more simplistic IP routing and use of polar codes for control plane). In 6G, we are going to see Tera Hz band allocated for mobile network. Saying mmWave is not 5G is not accurate. You would not have needed 1000s of pages of standards for FR1, with little enhancement, LTE would have supported.

[cycomanic]

I don't get your post. On the one hand you say that you need to go to FR2, due to higher throughput requirements. On the other hand you point out beam forming, MIMO etc. as the real difference between 4G and 4G. But that's exactly the technology used to get higher throughput. You don't need more bandwidth necessarily to get higher throughput, there is a D term in the Shannon formula, thus you can go to several spatial paths to increase throughput.

I doubt we will see _real_ THz comms in 6G, maybe we go up to a few 100s of GHz, but not THz (I know many in the industry use THz to mean anything from ~50GHz, but that's just marketing rubbish).

[Ballu]

Beamforming, MIMO, etc are not like you need for FR2, but without that you cant deploy. At this high frequency, the range is in 10s of m with antenna size of coin. To get the gain, you need MIMO and to get the distance, you need beam forming. Both MIMO and beam forming has more advantages, but without these technologies, almost impossible to deploy more than 50GHz. We will mmWave, but will take time. Thats how mobile world works. The high end of the targeted band is usually used at the end of particular generation of mobile or the next one. BTW, mmWave is having issue in adopting in mobile world not the FWA. My understanding is, both Lumen and Verizon are going ahead with mmWave band for FWA.

Regarding THz, FCC already opened the band till 3THz for 6G testing. I dont track, but next WRC might be planned for 2024 or 2025 (because of COVID, all the schedules are screwed up). The next WRC will kick start the standardization fo 6G and there is more possibility of THz to be part of 6G. Although as I mentioned earlier, my guess is, it more than a decade before THz band will be in use for mobility.