digital signal processing

You've probably noticed how everything is becoming digital these days -- and for good reason. Digital representation of signals over their analog counterparts has many advantages:

• Fewer Components
• Stable, deterministic performance
• Wide range of applications
• No filter adjustments
• Filters with much closer tolerances
• Adaptive filters easily implemented

DSP is the basis of many technologies and is commonplace in such devices as mobile phones, multimedia computers, video recorders, CD players, hard disk drive controllers, and modems, and will soon replace analog circuitry in TV sets and telephones. An important application of DSP is in signal compression and decompression. In CD systems, for example, the music recorded on the CD is in a compressed form (to increase storage capacity) and must be decompressed for the recorded signal to be reproduced. Signal compression is used in digital cellular phones to allow a greater number of calls to be handled simultaneously within each local "cell." DSP signal compression technology allows people not only to talk to one another by telephone but also to see one another on the screens of their PCs, using small video cameras mounted on the computer monitors, with only a conventional telephone line linking them together.