RFID people tracking

Dear Edaboarders, I need to build a multi access control for people tracking which should have very low price cause the big number of doors/windows in the structure. In my application I need to detect the ID of the person who walks through the gateways and I thought to use RFID passive technology with tags stiched in the clothes. At the moment we have a huge problem regarding costs of RFID readers (300S for a reader, definitely too much for the application)
Can someone give some advices like right RFID frequency, or other technologies, for mine application?

Thank you very much, regards

See this link :

http://www.ns-tech.co.uk/blog/2010/0...acking-system/



UHF RFID Tags & Labels operate on the global EPC Gen 2 standard at a global frequency range of between 860MHz and 960MHz or a regional subset such as 915MHz for USA, Australia and most of Asia or 868MHz for Europe, NZ and parts of Asia.UHF RFID tags have a read range of between 1cm and more than 35m ? depending on the specific tag and the environment in which it is being read.

http://www.ramp.com.au/uhfrfidtags.html

Thanx for the reply but in our application we need passive tags (no battery inside) and high distance reader (5-10m). Another bad aspect is that if the passive tag is stiched on clothes, part of the signal will be reduced from human body. I read about RuBee that is a technology similar to RFID but seems to much expensive.

You are not likely to get this large read range. 1m is the usual limit and that takes expensive readers.

UHF EPC Gen2 technology reads 5-15 meter. Limiting factors:
1. antenna gain
2. reader output power (27-30dBm is fine)
3. reader sensitivity

Most readers are capable of up to 5 meter reading distance when combined with a decent 6-8 dBi gain antenna. Even cheap deskreaders.
Maybe the MTI RU-861 with an external antenna will do the job? No idea about cost...
Tags directly on the body is an absolute no go. You need at least 5mm spacing, 10mm is better.

Take note that the often impressive read ranges given by supplies of ISO 18000-6c (EPC Gen2) compliant tags and readers assume perfect alignment of tag and reader antennas.

However, ISO 18000-6c is very orientation sensitive, so range will fall rapidly with increasing relative angle of tag and reader antennas.

This often rules ISO 18000-6c out for personnel tracking applications, because the tag's antenna orientation can seldom be controlled.