Battery assisted RFID tag

SCiprian

I am trying to create a battery assisted RFID tag, not active tag. The main concern is power consumption. The device works, but I am stuck on one thing.

How can I use a radio frequency or magnetic field to power the tag? Picture a sunpass, it is always off until you pass under the toll plaza. This is my senior design project, any help would be great.

John R.

SCiprian;

I have no direct answers, but have an interest in your solution.

What frequency and tag type are you working with?

I'm working with small passive tags and the Parallax RFID reader (125kHz). Adding active power to the tags might solve a couple problems I'm having.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
John R.

8 + 8 = 10

SCiprian

John,

I also attempted to use the rfid reader and tag from parallax, but the distance became a problem. My project is a passive rfid door locking system. I used parallax's reciever, transmitter, and javelin stamp to create a secure communication system. Now the problem is that I need power consumption and distance on the transmitter. I am thinking about using a hall effect transistor as a switch, but I dont know the operating distance or how big of magnetic field I'd have to create. Need help!

P.S.
The goal of this project is the ultimate in laziness. You wouldn't have to remove the tag from your pocket.