WhatisRFID?

 RFID consist of a sensing device which transmits a radio-frequency signal to a specially designed tag, which responds with another radio message. 

How does the trovan® system work?
The system consists of two basic elements: the passive transponder (the ID tag) and the reader. The reader emits a low-frequency magnetic field via its antenna. When a transponder passes within range, it is excited, causing it to transmit its ID code back to the reader. Transmission and reception occurs simultaneously. This makes for a very short read time. 

Does the transponder require maintenance?
No. The transponder contains no batteries and is

hermetically sealed in a housing designed to tolerate harsh

environmental conditions. The permanently programmed code is unique, counterfeit-proof and cannot be modified or deleted. Thus, each transponder is completely maintenance free and in principle has an unlimited life span.

 What provisions have been made for code security?
Complex automatic test methods ensure that no code exists in duplicate in any of the transponder types, and that the codes are programmed correctly in a readable manner. In each transponder, 39 bits of memory are reserved for the code. That translates 550 billion possible unique codes.

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