Digital Signal Processing
Digital Modulation
Computer Aided Design
The technology development of the nineties was driven by the introduction of „digital systems“. In the background the network technology became already digital by introduction of PCM in the transfer of voice signals. For the „normal consumer“ the introduction of the CD made the concept and advantage of „digital storage“ visible or better „hearable“. This new digital world became possible with a new technology branch that is called Digital Signal Processing. The general approach of digital signal processing is described here: Digital Signal Processing. Beside the general „filtering“ of signals especially Speech Coding is described in more details. Furthermore a main building block, the Digital Signal Processor is described.
Speech Coding made it possible to compress speech signals. This has big advantage for the capacity of mobile telephone systems. To take advantage of digital processing, it must be assured that digital signals can be transferred via a radio link. This is achieved by Digital Modulation.
Beside developments in digital signal processing, the eighties and nineties showed improvements in the way Integrated Circuits are designed, especially so called ASICs. This was achieved especially by Computer Aided Design.