DLSU-Manila: WISE

Wireless

Wireless refers to telecommunication using electromagnetic waves, rather than wires, to carry signals over parts or the entirely of a communication path. An example is intrusion alarms which operate using acoustic waves at frequencies above the range of human hearing.

The first wireless transmitters went on the air in the early 20th century using radiotelegraphy (Morse code). Later, modulation made it possible to transmit voices and music via wireless means. The medium was referred to as "radio." With the advent of television, fax, data communication, and the effective use of a large portion of the spectrum, the term "wireless" has been used.

Wireless Equipment

Common examples of wireless equipment in use today include:

• Cellular or mobile phones, pagers and Personal Digital Asistants (PDAs) - provide connectivity for portable and mobile applications, both personal and business.
• Global Positioning System (GPS) - allows drivers of cars and trucks, captains of boats and ships, and pilots of aircraft to ascertain their location anywhere on earth.
• Cordless computer peripherals - examples of these are cordless mouse, keyboards and printers which can be "linked" to a computer wirelessly
• Cordless telephone sets - these are limited-range devices, not to be confused with cell phones
• Home-entertainment-system control boxes - the VCR control and the TV channel control are the most common examples; some hi-fi sound systems and FM broadcast receivers also use this technology.
• Remote garage-door openers - one of the oldest wireless devices in common use by consumers; usually operates at radio frequencies.
• Two-way radios - this includes Amateur and Citizens Radio Service, as well as business, marine, and military communications.
• Baby monitors - these devices are simplified radio transmitter/receiver units with limited range.
• Satellite television - allows viewers in almost any location to select from hundreds of channels.
• Wireless LANs or local area networks - provide flexibility and reliability for business computer users.

Wireless Communication

Wireless technology continues to evolve rapidly and has become the standard mode of communication among people throughout the world. A growing number of people relies on this technology directly or indirectly. At other times, overuse of wireless communication has been creating social nuisance. Specialized forms of wireless communication and control include:

• Global System for Mobile Communication (GSM) - a digital mobile telephone system used in Europe and other parts of the world; the wireless telephone standard in Europe.
• Global Positioning System (GPS) - allows drivers of cars and trucks, captains of boats and ships, and pilots of aircraft to ascertain their location anywhere on earth.
• General Packet Radio Service (GPRS) - a packet-based wireless communication service that provides continuous connection to the Internet for mobile phone and computer users.
• Enhanced Data GSM Environment (EDGE) - a faster version of the Global System for Mobile (GSM) wireless service.
• Universal Mobile Telecommunications System (UMTS) - a broadband, packet-based system offering a consistent set of services to mobile computer and phone users no matter where they are in the world.
• Wireless Application Protocol (WAP) - a set of communication protocols to standardize the way wireless devices such as cellular telephones and radio transceivers, may be used for Internet access.
• i-Mode - the world's first "smart phone" for Web browsing, first introduced in Japan; provides color and video over telephone sets.

Wireless Operation and Usage

Wireless can be divided into:

• Fixed wireless - the operation of wireless devices or systems in homes and offices, and in particular, equipment connected to the Internet via specialized modems.
• Mobile wireless - the use of wireless devices or systems aboard motorized, moving vehicles; examples include the automotive cell phone and PCS (personal communications services).
• Portable wireless - the operation of autonomous, battery-powered wireless devices or systems outside the office, home, or vehicle; examples include handheld cell phones and PCS units.
• IR wireless - the use of devices that convey data via IR (infrared) radiation; employed in certain limited-range communications and control systems.