Active RFID tags

Figure 12.1 Active RFID tags contain small batteries (or solar microcells). As a consequence, they are able to alert receiving and tracing systems...

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-... 

The rectifier in an HF RFID application needs to be able to rectify at 13.56 MHz, and current standards require the clock be divided from this same frequency as well. The former appears to be possible with printed electronics. The latter is problematic however it is possible to generate a kHz clock locally using an oscillator, i.e., without dividing down from 13.56 MHz. This introduces more variability and noise into the tag, but, for low data rates, the reader can screen this out. As a result, it is hkely that a 13.56 MHz printed RFID tag is realizable, albeit with a local clock and a low data rate. This appears to be usable for many apphcations including authentication, anti-coimterfeiting, etc., and therefore, there is substantial industrial and research institute activity in this regard. The driver, of course, as in displays, is the development of printed transistors. 

Printed RFID-tags have already been demonstrated by companies active in the printed electronics industry. At the Organic Electronics Conference (OEC) 2007 in Frankfurt, in each conference-ticket an RFID-tag fabricated by Poly-IC (http //www.polyic.com) was incorporated [8]. 

Research is conducted in-house, as well as by a multitude of scientific cooperation partners, like universities and research institutes. Industrial partners include innovative companies like printed systems. Creavis participates actively in multiple European and BMBF-frnanced projects. The Nanomatch project (http //www.nanomatch.eu), in which new hybrid devices are developed, and the MaDriX project (http //www.madrix-projekt.de) that focuses on the development of printed RFID-tags, are just two examples. Next to such projects, Creavis is also a member of international research and development networks, like the Organic Electronics Association (OEA) and the Dutch Polymer Institute (DPI). Membership of these networks enables Creavis to keep a close eye on the market, in order to respond as fast as possible to new trends and demands. 

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

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 ... 

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,...

The last point is very evident in the EU where active packages, in direct contact with food atmospheres, are considered extraneous or incompatible with fresh foods [1]. In contrast, Japanese consumers tend to prefer active packaging while RFID tags... 

RFID interr( ator (reader). The RFID transponder or the RFID tag (which is how it is often called) is a microchip connected to an antenna. This tag can be attached to an object, which needs to be uniquely identified, for example, it can be used in a warehouse to track the entry and exit of goods. This tag contains information similar to the barcode, which stores the unique properties of the object to which it is attached. An RFID reader can access this information. The RFID reader communicates with the RFID tag using radio waves. The radio waves activate the RFID tag to broadcast the information it contains. Depending on the type of tag used, the information transmitted could be merely a number or detailed profile of the object. The data fetched from the reader can then be integrated with the backend ERP or SCM or WMS systems (Tecstra, n.d.). 

A typical RFID system is shown in Figure 1. When the RFID tag comes in the range ofthe RFID reader, the reader activates the tag to transmit its unique information. This unique information is propagated to the RFID middleware, whieh appropriately processes the gathered information and then updates the baekend database. 

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. 

The organic field effect transistor (OFET) acts essentially as an electronic valve by modulating the semiconductor channel conductance via the gate field. This device is essential in all electronic applications, including integrated circuits for memories and sensors and also to drive individual pixels in active matrix displays. Probably one of the most exciting applications of organic electronic circuits is in the supply chain area, where radiofrequency-powered elements (e.g. RFID tag) may replace ID barcodes for identification and be applicable as a backplane drive for displays. 

Manufacture of formed embedded active devices has been demonstrated, but not produced commercially. An example is polymer semiconductor radio frequency identification (RFID) tags. Conventional RFID devices, now in mass production, use a tiny silicon integrated circuit, made conventionally and bonded to the antenna. Semiconducting polymers make up the source, drain, and gate of the integrated circuit and are applied by inkjet or screen printing. 

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. 

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