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(+7-812) 274 6078, 274 5623.
General principle of operation of any RFID system is rather simple. System shall always include two basic components: Reader and Identifier (card, tag, badge.) Reader generates electromagnetic waves into environment. Identifier receives the signal from Reader and forms a response received by Reader’s antenna and processed with its Electronic Control Unit.
The demand in interactive systems has resulted from the necessity of simultaneous operation of more than one Identifier, e. g., when it is required to read all tags at goods packaging in the warehouse. In such cases anticollision mechanism capable to provide random alternate performance of several Identifiers simultaneously located within Reader's field will be a must. Otherwise Identifier signals would overlap each other. In the course of anticollision procedure Reader detects all Identifiers by their unique serial numbers and then processes them one-by-one.
To make a decision on person access to premises or to calculate boxes on a pallet it is sufficient that each Identifier has its unique serial number. On the other hand there is a wide range of tasks, when the tag shall include additional data reflecting the progress of operating procedure.
Frequency Range and Standards
Currently the high frequency range is the most popular. It is used ticketing systems and similar applications, where writable cards are required. ISO 14443 is the basic standard and actually all smart-cards are produced in accordance with this standard.
Two standards are of interest within medium frequencies range: ISO 15693 and EPC.
ISO 15693 is mainly used for writable tags fabrication with rather wide functionality. EPC (electronic product code) has a simpler structure and is an electronic analogue to strip codes.
Ultra high frequency range (800 MHz - 2.45 GHz) has recently come into use and it is of great interest due to the fact that under existing standards of generation power within this range passive Identifiers have coverage up to 4 - 8 m that is critical for warehouses, for example. Two standards prevail in this range: ISO 18000 and EPC.
Nowadays it can be taken for granted that EPC for medium and high frequency ranges is very promising for logistics systems in particular.
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