30 Years of Communications Technology
- Thursday, 04 January 2007
The most basic form of communication is speech, but for those who are unable to speak, effective communication is anything but basic. Augmentative and alternative communication (AAC) refers to ways in which people communication other than through speech.
Prior to the popularity of the PC, augmentative communication tools featured symbols that conveyed general concepts, and were combined to form words. With the introduction of the PC, software and electronic devices became available that could speak in response to entries on a keyboard or via other input such as the push of a button or a puff of air.
Today, computer-based AAC devices and equipment take advantage of technology advances in graphics, speech synthesis, and software. A number of handheld communication devices are available that act as speech-generating devices. These allow the speech-impaired user to communicate by selecting words or phrases from prerecorded buttons, and combining them to create a single message that is output in a clear voice.
Radio Frequency IDentification (RFID)
Gaining popularity in recent years is RFID, an automatic method of communicating location and identifying products — or even people and animals. An RFID tag is attached to or put into a product and a transponder receives data from the tag using radio waves. Passive RFID tags do not have an internal power supply; they signal by backscattering the carrier signal from the reader. Because they require no power supply, passive tags can be very small — small enough to be embedded under the skin of a person or animal.
Active RFID tags do have a power source to power the circuits that generate an outgoing signal. Active tags can be used in challenging environments such as within metal containers or in water. Active tags can communicate information on products such as temperature of perishable goods, humidity, light, and radiation exposure.
RFID tags are used today on everything from library books to passports. They are used for automatic toll collection on highways, airline baggage tracking, ID badges, and even credit cards. Implanted RFID tags are used for pet identification and location. Toyota has introduced a key using an active RFID circuit that enables the car to acknowledge the key’s presence within about three feet. The driver then opens the door and starts the car while the key remains in the driver’s pocket.