PLANT MAINTENANCE UHF readers for industrial production

Industrial production plants present a difficult challenge to radiobased systems. The readers are sometimes located very close together and may influence each other. There is also only a small distance between the work-piece holders and therefore between the transponders, which have to  be detected individually. Metal surfaces reflect the signals transmitted by the readers, which leads to superimposition of the radio waves and consequently radio fade-out. Apart from reflections, higher transmit powers can lead to overreach, so that the reading ranges of the individual readers overlap or the wrong data storage media are read out..

Siemens has added new functions to the latest generation of RFID readers in its Simatic RF620R and RF630R UHF system to optimise them for use in industrial production. The new functions ensure robust operation, even when several RFID readers are located in close proximity to each other. The readers use new algorithms to detect, read, and write data storage media reliably even in a difficult radio environment. This enables the Siemens UHF system to meet the specific requirements a production environment places on long-range, radio-based systems.

Process stability is substantially increased by an adaptive transmit power and intelligent filtering of the reading results. The adaptive transmit power ensures a high recognition rate because the reader automatically increases its power until it clearly detects at least one transponder in its RF field. This not only reduces radiofrequency interference but also compensates for radio fade-out. The multi-stage filter concept designed by Siemens uses the radio characteristics to ensure that the correct transponder in the RF field of a reader is always read or written. The appropriate data storage medium is automatically  selected on the basis of various indicators, such as the evaluation of the RSSI value (Radio Signal Strength Indicator), the reading frequency, or the transmit power required.

The new RF620R and RF630R devices are being introduced in three hardware versions based on the following standards: ETSI for Europe, FCC for the United States and Canada, and CMIIT for China. Future firmware updates can be handled using the Step7 programming software.
Source: Siemens (www.siemens.com)