arduino - Long Range RFiD Reading -

i'm trying set practical diy method of unlocking garage or front door coming range of reader; if means standing in specific line of sight. once reach garage, id read , raises

i'd prefer have passive id's, reader able have fixed power source doesn't need changed.

i've done lot of searching on google , there are rfid scanners read cars open tolls booths, commercial grade products , more expensive i'm trying make. should continue looking rfid's, or there more efficient method of approaching this?

also, if tags active, , powerful enough, compensate low frequency reader?

you'll achieve read passive tags distance of few meters (up 10m) using industrial uhf rfid reader (impinj, thingmagic, stid, ...). tags similar labels can directly stuck on windscreen of cars. tags rather inexpensive. in case need spend few hundreds of dollars buy single reader antenna.

that makes me think rfid based system option when number of users of system quite important (i.e: check access company park or residence).

in case, investment of reader dispatched on users, whereas global investment tags stay low.