April 10, 2011
A wireless signal is a signal that is transported through the atmosphere. Both analog and digital signals are used to transmit data. Radio frequency (RF), Microwave signals, Satellite signals, and Infrared systems are all wireless signals. Each of these different signals are associated with a specific frequency on the wireless spectrum.
Radio frequencies have been used for decades that reside between 10 KHz and 1 GHz of the electromagnetic spectrum. Shortwave radio, VHF, and UHF all use radio frequency to transmit data. Low frequency radio waves have the advantage of passing ...view middle of the document...
The satellites used for this type of data transmission are required to be located 22,300 miles above the earthâ€™s equator and needs to be traveling at the same speed as the earth to maintain a fixed location. This is called geosynchronous orbits. Satellite signals are used for different applications including satellite television and internet connectivity.
Infrared systems or IR is the transmission of light that is just below the visible light in the electromagnetic spectrum (Regan, 2004). Light emitting diodes (LEDs) or injection laser diodes (ILDs) are used to transmit signals and photodiodes are used to receive signals. These signals are transmitted in light frequency ranges of 100 GHz â€“ 1000 THz. IR is limited in the amount of data that can be transmitted. For omnidirectional communications only up to 1 Mbps can be transmitted and for directional communications up to 16 Mbps can be transmitted. IR is not able to penetrate opaque objects so must have a direct line of site or point to point technology to be used. Infrared light can bounce off of objects so this type of data transmission is not very secure. The most...