Wireless PSTN

Is wireless PSTN possible?

In theory sure at least on a small scale, on a large scale in densely populated areas no. Generally it's not even considered, dynamic distribution of transmission space is superior in all but high reliability applications, and for that wireless isn't even a consideration in the first place.

For wired PSTN means we can go for E1/T1 Transceivers, but what about wireless PSTN......