Anti Collision algorithms for Active RFID

Hello everyone,
I've been trying to locate some algorithms for implementation of anti-collision algorithms in active RFID technology.

I've come across the aloha, slotted aloha, binary tree search and Q (?) algorithms but the problem with these seems to be that they are applicable to passive systems. Does anyone know of an anti-collision algorithm for use in active systems that continuously (or say once every 5-10 seconds) transmit their ID's?

I'd appreciate any help and especially, articles, papers documents uploaded here or in the document section of this board.. there are some available in the IEEE but I'm not a member anymore and i'm sure everyone here knows that even if you are a member, that definitely does not give you access to all the journals available.. :(
(What happened to the talk about making all Fed Gov. research free? :))

Appreciate any help..
Ananth.

P.S. I tried looking through the posts on the forum but couldn't find anything about this particular topic.

Hello,

did you try the "ARRA" (an enhanced slotted ALOHA)?

Slotted ALOHA is 36% efficency, Pure ALOHA is 18%.. ARRA is about 54%.

Give a look at "Satellite Communications Systems", Maral Bousquet.

Are you designing a system?

Regards,

Lupin