Digital signal processing is the manipulation of digital signals into other forms using computing circuits or systems. Digital signal processors use software programs to allow them to perform complex signal processing operations such as filtering, modulation, data compression, and shaping of the information (such as digital audio signal) that are represented by digital signals.

When analog signals are converted to digital format, the digital signals represent the original analog waveform. Just like analog signals that may be processed by filters, shaping circuits, combiners and amplifiers, digital signals can be processed to produce similar functions. To change a digital signal, a microprocessor is used to manipulate the incoming digital information via a program (stored instructions) that produces a new digital output. The program determines the functions that are performed in the digital signal.

Because radio signals can experience signal distortion that can result in the incorrect determination of a digital signal (whether a zero or one had been sent), digital systems typically include error detection and correction processing. Error detection processing involves the creation of additional bits that are sent with the original data. The check bits are created by using a formula calculation on the digital signal prior to sending the data signals. After the digital signal is received, the formula can be used again to create check bits from the received digital signal. If the check bits match, the original digital signal was received correctly. If the check bits of the received data signal do not match the calculated...