## RFID Technology  
RFID technology has been implemented in diverse environments providing significant benefits to the development of different processes. The advantages of its integration into the healthcare environment are widely recognized: the FDA is studying its viability for labeling certain types of medicines to avoid counterfeiting. The technology emerged in 1940 and its origin is related to the development of other technologies such as computers, mobile telephones, wireless networks, satellite communications and GPS. The United States military employed an RFID system to remotely identify possible attacks using the classification (Friend or Foe) emitted from any detected plane. At the end of the war, a period of slow but continuous research into this technology began. The publication \"Communications by Means of Reflected Power in the Proceedings of the Institute of Radio Engineers\" by [PERSON] in October 1948 can be considered the first research publication into RFID [7]. The diversity of components of RFID technology allows for the building of a large number of different systems. However the working method for all systems is the same: a tag attached to the object or person you want to identify emits a radiofrequency signal with identifying information; a reader receives it and sends the data to a computer application which processes it. This process is illustrated in Figure 1.  
The readers can be fixed (antennas, arc-shaped, access points etc.) or mobile (tablets, PDAs, telephones, etc.) The readers can be active if they possess their own energy source for transmitting, passive, if they use the reader as their energy source or semi-active if their own energy source is not used for transmissions but for feeding the internal circuitry of its microchip. There are other significant differences between passive and active tags: cost, available sizes for each of them and the fact that the coverage range is greater with active tags as can be seen in Table 2.  
Nowadays, RFID is considered to be a state-of-the-art technology and is deployed in a range of environments. However, a major disadvantage is its elevated cost for certain applications and the lack of automation in some of the processes necessary for its implementation. Therefore, implementing this technology, especially into a healthcare environment with its particular complexity, requires extensive research of those parameters detailed below in order to gain sufficient knowledge to maximize the possibilities and benefits that the technology offers:  
* The information to be stored will determine the type of memory in the tag (read-only, write-once or more)
* The tag material: it may deteriorate with use and depends on the aggressiveness of the surroundings
* The shape of tag which depends on the item that is to be identified and/or located
* The adhesive of the tag will depend on the item to be identified and/or located. Special adhesives exist for healthcare products to avoid penetrating, for example, serum or plasma
* The location or protective covering of the tag depends on the item that is to be identified and/or located to avoid any interferences in its readings e.g., attached to materials which contain metal, plastic liquids or glass \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Fixed Reader** & **Mobile Reader** & **Active Tags** & **Passive Tags** \\ \hline Antenna & Tablet & Battery & No Battery \\ Arcs & PDA & More expensive & Less costly with less coverage \\ Access points & Mobile telephone & Greater size & Longer life \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Comparison between Readers and RFID tags. Figure 1: The functioning of RFID technology. * The operating frequency of RFID components which will condition the distance at which the tags can be read  
This information facilitates the choice of technical architecture for a specific environment and contributes to the successful implementation of an RFID system.