content: For imaging purposes, and for greater location accuracy. Modern CDMA (Verizon et.al) is below GSM (AT&T et. al) in frequency, and is low enough to not be useful for imaging purposes. WIFI, by contrast, is in the 2.4 GHz band, which has enough resolution to determine large objects in a room (furniture locations and layouts), as well as the general shape of the room, but is useless beyond that. The main source I wanted to link from SIGGRAPH I can no longer find (it was the (((usual suspects))) ), but this is a modern take on using a common wifi router to inspect baggage, and this is using a common router and receiver to count objects between them. 5G is 28Ghz, or millimeter wave. It has enough imaging resolution to see weapon positions on the body (hence why it is used in airport scanners), and they have assloads of experience with imaging with millimeter waves from said airport scanners. They will not be as accurate as airport scanners, as airport scanners are typically 60 Ghz, vs 5G's 28. However, 5G will represent a 15.5 fold increase in imaging resolution over what is currently possible with common cell towers, and an 11.6 fold increase in imaging resolution over what is currently possible with common wifi routers. I seriously encourage everyone to do more research into this. I'm still compiling my own research, but I am learning to save everything. Things are already disappearing. Bonus: tracking multiple objects in a room with commodity WIFI.