What Does Frequency-Shift Keying (FSK) Mean?
Frequency-shift keying (FSK) allows digital information to be transmitted by changes or shifts in the frequency of a carrier signal, most commonly an analog carrier sine wave. There are two binary states in a signal, zero (0) and one (1), each of which is represented by an analog wave form. This binary data is converted by a modem into an FSK signal, which can be transmitted via telephone lines, fiber optics or wireless media.
Techopedia Explains Frequency-Shift Keying (FSK)
For example, a low-speed Hayes-compatible modem uses an unbit FM technique. When no digital information is transmitted, the frequency is 1,700 Hz. When a one is transmitted, the frequency shifts to 2,200 Hz. When a zero is transmitted, the frequency shifts to 1,200 Hz. The number of these frequency shifts per second is measured as the baud or modulation rate. Thus, a 2,400 baud modem can process zeros and ones from a computer at the rate of 2,400 bits per second using FSK. This is the simplest digital communication, where baud and bit rate are the same and measured in bits per second.
