Improvements in the reading of tags in library applications

摘要

The process for reading RF-ID type contactless identification labels uses a number of aerials, each of which is supplied with equal power. A division device is used to divide the available power for equal distribution to each of the aerials in use. The process uses RF-ID type contactless identification labels which are fixed on to articles to be identified, the articles being situated close on to another. A reading and recording system is provided, with a power supply. The reading/recording system includes a number of aerials, each of which is supplied with a power which is equal to the total power available (P) divided by the number of aerials (n) in operation. A division device is used to divide the available power for equal distribution to each of the aerials in use. The aerials may have an impedance of 50 ohms, and a null phase shift, operating at a frequency of 13.56 MHz. The output power applied to the aerials may be between 1 and 2 watts.