## RFID Technology
A wide range of identification technologies are now present in the market that could allow for the tracking of patients and medicines in the process of prescription-validation-elaboration-administration of pharmaceuticals by the Pharmacy Service and Day Hospital at CHUAC. However, the success of RFID technology with respect to others principally lies in the extensive capacity of its tags to store information relating to its objects and subjects. This data can also be coded and protected using common standards. Its tags do not deteriorate with use given the variety of materials with which they can be produced such as epoxy which can withstand extreme temperatures (up to \(-21\)\({}^{\circ}\)C). Hundreds of tags can be read simultaneously without having to have direct contact with the reader. These properties make RFID an ideal technology for use in tracking systems in healthcare environments (for fridge and room temperature products, to identify patients, unit doses of medicine, diffusion pumps, defibrillators, etc.) The tags are, without doubt, the most important components of the RFIF system. Their design is totally conditioned by the objects or subjects under control. A wide range of tags (size and shape) are available, and together with a suitable protective cover, allow them to be read irrespective of the material to which they are attached. RFID, as a mature technology, is subject to a series of standards which regulate the interchange of information between devices. These standards, which apply to the identification, reading and exchange of data between devices, are called Electronic Product Code (EPC). EPC global is a consortium of leading organizations in the market and include companies such as Cisco Systems, LG Electronics, Lockheed Martin Corporation and universities, including the Massachusetts Institute of Technology. The coverage of an RFID component describes the maximum distance at which communication can be maintained with it (to read or write data in its memory, change parameters in the configuration, etc.... ). The range depends on other factors besides the operational frequency of the system such as the antenna power of the reader available on the tag, environmental conditions and the direction of the tag when reading, etc. The designated values are, therefore, primarily tentative. An RFID system has four possible operational frequencies as outlined in Table 3.  
The operational frequency which functions at 13.56 MHz is now widely used in a range of environments and is now beginning to be deployed in the healthcare environment. This is called NFC and allows for the reading/writing of data in real time on passive RFID tags at a few centimeters distance. The principal difficulty involved in implementing an RFID system is in the selection of optimum values for the configurable parameters of RFID components. It is, therefore, necessary to evaluate the specific characteristics of each scenario as outlined below:  
* Wall materials that may interrupt or reduce radio frequency signals
* Lifts that may complicate the locating of control objects
* Types of rooms (open or semi-open plan)
* The material of the objects to be controlled which may produce interference
* The number and location of access points \begin{table}
\begin{tabular}{c c} \hline \hline
**Operational Frequency** & **Band** \\ \hline Low Frequency & Below 135 kHz \\ High Frequency & 13.56 MHz \\ Ultra-High Frequency & 433 MHz, 860 MHz and 928 MHz \\ Microwave & 2.45 GHz and 5.8 GHz \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Operational frequencies in RFID technology. RFID will manifest interference with certain materials which complicate its readings, especially if the tags are attached to metals, liquids in plastic or glass. In some cases, it may be necessary to apply a cover to the tags or position them carefully so that readings are error free. The design process of the technical architecture will be largely determined by the experience of the engineers responsible for the project.