Passive RFID tags

Recently, the Holst centre (http //www.holstcentre.com) demonstrated a 64 bit passive RFID-tag approaching technological requirements for item-level tagging [9]. The data could be read from 10 cm distance with a 780 bit/s data readout, fivefold higher as current state of the art bit rate in plastic electronics. 

In the second level of classification, (passive) RFID tags are classified based on the manner in which they conununicate with the reader. This is performed based on the frequency at which the reader broadcasts information and power to the tag. In general, the frequency bands already used for RFID around the world are (1) below 135 kHz (2) 13.56 MHz (3) 900 MHz and (4) 2.4 GHz. 

FIGURE 6.1.2 Block diagram of archetypal HP passive RFID tag. 

Figure 12.2 Passive RFID tags are not able to activate the reading/receiving system (distance up to 10 cm frequency 1 Hz, Resolution 100 pm). On the other hand,...

Another potentially interesting application of OFETs is in low cost RFID tags and logic elements. If transistors, passive elements, and the tag antenna can be produced simultaneously using continuous printing processes, it is conceivable that economies similar to those achieved in paper printing can be achieved. 

RFID tags can be divided into three types passive, active, and semi-passive. A passive tag... 

Yin, J, and Yuen, M. A System-on-Chip EPC Gen-2 Passive UHF RFID Tag With Embedded Temperature Sensor, IEEE Journal of solid state circuits, vol. 45, no. 11, pp. 2404-2420,2010. 

Zong, H-Q. et al. An ultra low power ASK demodulator for passive UHF RFID tag, IEEE 9th International Conference on ASIC (ASICON), pp. 637-640,2011. 

For all-printed thin film transistors (TFT), various organic and inorganic metal electrode materials, such as conductive polymer, carbon nanotube (CNT), organic metal compound, or metal nano-particles, have been used as gate and source/drain electrodes [6-11] in a combination with inkjet- and laser-based printing methods. One of the immediate applications for all-printed TFT would be flexible or rugged display backplane and disposable radio frequency identification (RFID) tags. In addition, printed metal electrodes and TFT have also been used to fabricate passive circuit components, power transmission sheets and sensors for ambient electronics and electronic skin [12-13]. 

On the other hand, passive - or battery assisted passive (BAP) - RFID tags are provided with very low cost batteries (cost 5) or completely inactive (up to 40 Eurocents). The difference is the impossibility of activating the reading/receiving system (distance up to 10 cm frequency 1 Hz, resolution 100 pm). This apparent limitation is the key of the success of RFID passive tags (Figure 12.2). Other advantages are ... 

RFID tags can be classified using three schemes. First, the tags can be classified based on their ability to perform radio communication—active, semi-active (semi-passive), and passive tags. Second, the tags can be classified based upon their memory—read-only, read-write or write-once, and read-many. Finally, the tags can also be classified based on the frequency in which they operate—LF, HF or UHF. 

Unlike passive tags, active RFID tags contain a battery to power the circuitry, and generate and transmit radio signals to the reader. Onboard power supply can enable long-distance communi-... 

With the increasing demand for automated inventory tracking and item identification, passive UHF RFID systems have been extensively adapted. As shown in Figure 10.31, an important application is to integrate these RFID tags into commercial truck tires to... 

RFID is an automatic identification method using devices called RFID tags or transponders. An RFID tag is an object that can be attached to or incorporated into a product, animal, or person for the purpose of identification using radio waves. Chip-based RFID tags contain silicon chips and antennas. Passive tags require no internal power source, whereas active tags require a power source. 

Keywords Radio-frequency identification, RFID, passive tag, temperature sensor, gas sensor, ASK, low power, system-on-chip, energy recovery. 

Beriani, A., Rebollo, I. and Berenguer, R. A Passive UHF RFID Pressure Sensor Tag with a 7.27 bit and 5.47pJ Capacitive Sensor Interface, IEEE MTT-S, p 1-3, 2012. 

Occhiuzzi, C., Contri, G., and Marrocco, G. RFID STEN Tag for passive vascular monitoring, Proc. 5th Eur. Antennas Propag. Conf, Apr. 11-15, pp. 3476-3478, 2011. 

Radio frequency identification (RFID) is growing rapidly in multiple end use segments such as transportation, security, and asset/inventory management. Polymer blends can be used in the housings, internals, and plastic films containing passive tags. 

It should be noted that a hybrid approach to design gas-sensing devices on plastic substrates can be used as well. In particular, a surface acoustic wave (SAW) chip, which require substrates with very different properties, can be transferred onto a plastic substrate Cobianu et al. (2007). Another interesting and new approach is the coating of passive (no power source on board) conventional RFID (radiofrequency identification) tags with chemically sensitive films to form a chemical sensor (Potyrailo and Morris 2007). The detection of several vapors of industrial, health, law enforcement, and security... 

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