What you want to do (read a lot of tags with one antenna) entails:
- Long(er) distances
- Proper collision detection
Meaning, if you do your homework, you’ll find the only kind of RFID system that’ll work for you is UHF - and not the cheap stuff. Matter of fact, is there any cheap UHF?
In short, if you want a reliable system, it’ll cost you a bundle. Other than that, yeah it sounds interesting.