| The term wireless is normally used to refer to | | | | previously manufactured with hard wired remote |
| any type of electrical or electronic operation which | | | | controls which plugged in to a receptacle or jack |
| is accomplished without the use of a "hard wired" | | | | in the television whereas more modern televisions |
| connection. Some of these operations may also | | | | use wireless (generally infrared) remote control |
| be accomplished with the use of wires if desired, | | | | units. |
| while others, such as long range communications, | | | | Cellular telephones |
| are impossible or impractical to implement with | | | | Perhaps one of the most well known examples of |
| the use of wires. The term is commonly used in | | | | wireless technology in action is the cellular |
| the telecommunications industry to refer to | | | | telephone. These instruments use radio waves to |
| telecommunications systems (e.g., radio | | | | enable the operator to make phone calls from |
| transmitters and receivers, remote controls, | | | | many locations world-wide. They can be used |
| computer networks, network terminals, etc.) | | | | anywhere that there is a cellular telephone site to |
| which use some form of energy (e.g.,radio | | | | house the equipment that is required to transmit |
| frequency (RF), infrared light, laser light, visible | | | | and receive the signal that is used to transfer |
| light, acoustic energy, etc.) to transfer information | | | | both voice and data to and from these |
| without the use of wires.[1] Information is | | | | instruments. |
| transferred in this manner over both short and | | | | History |
| long distances. | | | | The term "wireless" came into public use to refer |
| The term "wireless" should not be confused with | | | | to a radio receiver or transceiver (a dual purpose |
| the term "cordless", which is generally used to | | | | receiver and transmitter device), establishing its |
| refer to powered electrical or electronic devices | | | | usage in the field of wireless telegraphy early on; |
| that are able to operate from a portable power | | | | now the term is used to describe modern |
| source (e.g., a battery pack) without any cable or | | | | wireless connections such as in cellular networks |
| cord to limit the mobility of the cordless device | | | | and wireless broadband Internet. It is also used in |
| through a connection to the mains power supply. | | | | a general sense to refer to any type of operation |
| It is interesting to note that some cordless | | | | that is implemented without the use of wires, |
| devices, such as cordless telephones, are also | | | | such as "wireless remote control", "wireless |
| wireless in the sense that information is | | | | energy transfer", etc. regardless of the specific |
| transferred from the cordless telephone to the | | | | technology (e.g., radio, infrared, ultrasonic, etc.) |
| telephone's base unit via some type of wireless | | | | that is used to accomplish the operation. |
| communications link. This has caused some | | | | Heinrich Rudolf Hertz |
| disparity in the usage of the term "cordless", for | | | | Possibly the most important discovery in the |
| example in Digital Enhanced Cordless | | | | history of wireless technology was the |
| Telecommunications. | | | | demonstration by Heinrich Rudolf Hertz in 1888 |
| Examples of wireless technology at work | | | | that electromagnetic waves exist as predicted by |
| Security systems | | | | James Clerk Maxwell and Michael Faraday. He also |
| One common example of an operation or | | | | proved that these waves could be transmitted |
| operations where the implementation of wireless | | | | and caused to travel through space and that they |
| technology may supplement or replace hard wired | | | | were able to be received by an experimental |
| implementations is in security systems for homes | | | | apparatus.[2][3] The experiments of Hertz proved |
| or office buildings. The operations that are | | | | to be very important to the fields of wireless |
| required (e.g., detecting whether a door or | | | | communication and remote control, though |
| window is open or closed) may be implemented | | | | practical applications of the technology would be |
| with the use of hard wired sensors or they may | | | | implemented by others. |
| be implemented with the use of wireless sensors | | | | Nikola Tesla |
| which are also equipped with some type of | | | | Some principles and inventions of wireless |
| wireless transmitter (e.g., infrared, radio | | | | technology can be found in the lectures, patent |
| frequency, etc.) to transmit the information | | | | record, and other accounts of the electrical |
| concerning the current state of the door or | | | | engineer Nikola Tesla (such as his 1916 deposition |
| window. | | | | on the history of wireless and radio technology: |
| Television remote control | | | | 'Nikola Telsa On His Work With Alternating |
| Another example would be the use of a wireless | | | | Currents And Their Application to Wireless |
| remote control unit to replace the old hard wired | | | | Telegraphy, Telephony, and Transmission of |
| remote control units that were sometimes used in | | | | Energy, Anderson, Leland, ed., Published 1992). |
| the television industry. Some televisions were | | | | |