A signal is a piece of information in binary or digital form. Digital Signal Processing techniques improve signal quality or extract important information by removing unwanted parts of the signal.
The introduction of general-purpose microprocessors in the late 1970s and early 1980s made it possible for DSP techniques to be used in a much wider range of applications. The microprocessors such as the Intel x86 family were not suitable for the numerically-intensive requirements of digital signal processing, and the increasing importance of DSP led major electronic manufacturers to develop DSP chips, the design of which met all the requirements of digital signal processing.
DSP is a programmable chip and is capable of carrying out millions of floating-point operations per second. Typical DSP application fields are audio signal processing, video signal processing, image processing, and telecommunications devices. DSP is the basis of many technologies including mobile phones, personal computers, video recorders, CD players, hard disc drive controllers, and modems.
The application of digital signal processors in cellular phones is very significant. Signal compression, an important application of DSPs, is used in cellular phones to permit a larger number of calls to be handled simultaneously within each local “cell”. The signal compression technology helps to communicate with one another by seeing them while talking. This facility is available with the help of a computer monitor, a small video camera and a conventional telephone line linking them together. DSPs can be used in applications that require a high computational speed. Such applications include computer video boards and specialized co-processor boards designed for intensive scientific computation.