Directional 1m range RFID tag reader

I have an application where RFID tags will be passing by a que zone in rapid succession. I need to record the time each of these tags passes by the same location. I am on the hunt for an economical solution. I have room for a cable the be run below the RFID tags, which will pass overhead within .4m; or from the side, where they will pass within 1-2m of the sensor.

The most important part is to accurately record the timestamp for each of these tags at the same location (and among the company of 10 or so other RFID tags.)

Can anyone point me in a direction to start my hunt? I have found previously discussed short-range RFID solutions to be to miniature for my application, or unable to handle multiple RFID tags.

My most exceptional challenge as of right now is determining the hardware. -Antenna -Small RFID tags (potato chip size or smaller is fine)

Thanks in advance!

The words economical solution and RFID where they will pass within 1-2m of the sensor are mutually exclusive.

There is no low cost solution for a reader with such a long range. In fact you will struggle to find a high cost solution. You want to use what is known as an active tag. These have small batteries in them and allow for a much longer range than normal.

Ha, well this is exactly what I need to know. Well what if I went with an active tag? Or should I consider something completely different from an RFID system?

I just need to know when something passes a point. Is there another elegant solution that may be able to distinguish one 'tag' from another?