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