Re: RFID reader design

Andy comments:

Here's a suggestion.... Just put a reader on each doorway
and keep track of whether the tag has passed thru the
doorway.... It wouldn't require direction OR distance, and a
simple software routine would tell you which room the TAG
is in....( If it was in room A, and the door on room A then
registers a "hit" it is no longer in room A but has moved to
room B --- that sort of thing , not foolproof but reasonable )
Also the read distance would need to be less than a meter,
so you could use a LOT less power --- the reader has to
continually illuminate for a passive tag, so low power is a
big plus for avoiding brain cancer and bad stuff.....

Also, battery life in a semi-passive or active tag
is in the neighborhood of 5 years, and the batteries
are very cheap, so that would cut the illuminator power down
even more since the tag doesn't have to draw power energy
from the illuminator field, only "wake-up" energy....

Just a suggestion... I really miss working on those kinds of
projects, but everyone has to hang it up sometime....

If you would like to throw ideas around, I'd be please to
correspond... My email is andysharpe@xxxxxxxx


Andy in Eureka, Texas

( If you have more owls in your yard than dogs, and
all the cats have disappeared, you probably live
in Eureka, Texas )

.

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