31-05-2012, 12:56 PM
Wireless Communication
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples ofwireless technology include GPS units, Garage door openers or garage doors, wireless computer mice, keyboards and Headset (telephone/computer),headphones, radio receivers, satellite television, broadcast television and cordless telephones.
Introduction
Wireless operations permit services, such as long range communications, that are impossible or impractical to implement with the use of wires. The term is commonly used in the telecommunications industry to refer to telecommunications systems (e.g. radio transmitters and receivers, remote controls, computer networks, network terminals, etc.) which use some form of energy (e.g. radio frequency (RF),acoustic energy, etc.) to transfer information without the use of wires.[1] Information is transferred in this manner over both short and long distances.
Modes
Wireless communications can be via:
radio frequency communication,
microwave communication, for example long-range line-of-sight via highly directional antennas, or short-range communication,
infrared (IR) short-range communication, for example from consumer IR devices such as remote controls or via Infrared Data Association (IrDA).
Wireless data communications
Wireless data communications are an essential component of mobile computing.[6] The various available technologies differ in local availability, coverage range and performance[7][8], and in some circumstances, users must be able to employ multiple connection types and switch between them. To simplify the experience for the user, connection manager software can be used [9][10], or amobile VPN deployed to handle the multiple connections as a secure, single virtual network.[11]
Supporting technologies include:
Wi-Fi is a wireless local area network that enables portable computing devices to connect easily to the Internet[citation needed]. Standardized as IEEE 802.11 a,b,g,n, Wi-Fi approaches speeds of some types of wired Ethernet. Wi-Fi has become the de facto standard for access in private homes, within offices, and at public hotspots.[12] Some businesses charge customers a monthly fee for service, while others have begun offering it for free in an effort to increase the sales of their goods.[13]
Cellular data service offers effective coverage within a range of 10-15 miles from the nearest cell site.[7] Speeds have increased as technologies have evolved, from earlier technologies such asGSM, CDMA and GPRS, to 3G networks such as W-CDMA, EDGE or CDMA2000.[14][15]
Mobile Satellite Communications may be used where other wireless connections are unavailable, such as in largely rural areas[16] or remote locations.[7] Satellite communications are especially important for transportation, aviation, maritime and military use.[17]
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples ofwireless technology include GPS units, Garage door openers or garage doors, wireless computer mice, keyboards and Headset (telephone/computer),headphones, radio receivers, satellite television, broadcast television and cordless telephones.
Introduction
Wireless operations permit services, such as long range communications, that are impossible or impractical to implement with the use of wires. The term is commonly used in the telecommunications industry to refer to telecommunications systems (e.g. radio transmitters and receivers, remote controls, computer networks, network terminals, etc.) which use some form of energy (e.g. radio frequency (RF),acoustic energy, etc.) to transfer information without the use of wires.[1] Information is transferred in this manner over both short and long distances.
Modes
Wireless communications can be via:
radio frequency communication,
microwave communication, for example long-range line-of-sight via highly directional antennas, or short-range communication,
infrared (IR) short-range communication, for example from consumer IR devices such as remote controls or via Infrared Data Association (IrDA).
Wireless data communications
Wireless data communications are an essential component of mobile computing.[6] The various available technologies differ in local availability, coverage range and performance[7][8], and in some circumstances, users must be able to employ multiple connection types and switch between them. To simplify the experience for the user, connection manager software can be used [9][10], or amobile VPN deployed to handle the multiple connections as a secure, single virtual network.[11]
Supporting technologies include:
Wi-Fi is a wireless local area network that enables portable computing devices to connect easily to the Internet[citation needed]. Standardized as IEEE 802.11 a,b,g,n, Wi-Fi approaches speeds of some types of wired Ethernet. Wi-Fi has become the de facto standard for access in private homes, within offices, and at public hotspots.[12] Some businesses charge customers a monthly fee for service, while others have begun offering it for free in an effort to increase the sales of their goods.[13]
Cellular data service offers effective coverage within a range of 10-15 miles from the nearest cell site.[7] Speeds have increased as technologies have evolved, from earlier technologies such asGSM, CDMA and GPRS, to 3G networks such as W-CDMA, EDGE or CDMA2000.[14][15]
Mobile Satellite Communications may be used where other wireless connections are unavailable, such as in largely rural areas[16] or remote locations.[7] Satellite communications are especially important for transportation, aviation, maritime and military use.[17]