My project

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   I'm trying to figure out if RFID is the appropriate solution for what I'm trying to do.  Perhaps somebody can tell me if this idea is covered in the book, or is even possible.

I would like to use RFID to find lost items.  If I lose something in the house, I want to know if I'm looking in the right room.  I would only apply a few of the tags, so differentiating between different tags isn't too important.  I just want to know if there is a tag present in the room.

It would be really helpful if the system had about a 10-foot range.  It would be useless if the range were shorter than 3 feet.

Is this possible?  Is this covered in the book?

Thanks,
K

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kevinq2000 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 21 February 2006 Location: United States Status: Offline Points: 2	Post Options Post Reply Quote kevinq2000 Report Post Thanks(0) Quote Reply Topic: My project Posted: 21 February 2006 at 1:06pm
	I'm trying to figure out if RFID is the appropriate solution for what I'm trying to do. Perhaps somebody can tell me if this idea is covered in the book, or is even possible. I would like to use RFID to find lost items. If I lose something in the house, I want to know if I'm looking in the right room. I would only apply a few of the tags, so differentiating between different tags isn't too important. I just want to know if there is a tag present in the room. It would be really helpful if the system had about a 10-foot range. It would be useless if the range were shorter than 3 feet. Is this possible? Is this covered in the book? Thanks, K

amal Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Admin Group Joined: 22 November 2005 Location: United States Status: Offline Points: 2061	Post Options Post Reply Quote amal Report Post Thanks(0) Quote Reply Posted: 21 February 2006 at 8:28pm
	Yeah, you could use active RFID and multiple antennas for this purpose. It's a little spendy compared to passive RFID, but range is a big issue with passive, so you'll need to use active RFID. Chapters 8 and 9 cover active RFID and show you how to setup multiple antennas for tracking items and objects using a single reader.

kevinq2000 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 21 February 2006 Location: United States Status: Offline Points: 2	Post Options Post Reply Quote kevinq2000 Report Post Thanks(0) Quote Reply Posted: 22 February 2006 at 9:14am
	Thanks for the answer. I'll check that out. Out of curiosity, though, what is the general range of the passive RFID systems? K

athenaz Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 22 February 2006 Location: United States Status: Offline Points: 2	Post Options Post Reply Quote athenaz Report Post Thanks(0) Quote Reply Posted: 22 February 2006 at 10:57am
	From what I have read, passive devices need to be within inches of the reader. They have no power source of their own, so they are dependent on the reader. They aren't sending out a signal, so the reader has to be close to it.
	Jamie

amal Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Admin Group Joined: 22 November 2005 Location: United States Status: Offline Points: 2061	Post Options Post Reply Quote amal Report Post Thanks(0) Quote Reply Posted: 22 February 2006 at 12:17pm
	True, most passive systems have a limited range. Most of the time the range is limited to anywhere between a few inches to at most 3 or 4 feet. However, to be reliable at 4 feet, the tags have to be properly aligned with the reader antenna, not be around anything that would cause interferance like liquids (even your own body), or metals, and the environment must be very controlled. These types of setups are generally found in warehouses and inventory control facilities, not in your own home. Some large passive tags can be used with special high-powered, and highly expensive reader setups that use special antennas to increase the range significantly (20 feet), but the cost of setting this up is in the thousands of dollars... and you'd need one for each room.