2. Concept

2.1 Technological revolution: digitization

A major milestone was reached in the 1970s for on-board electronics: the all-analog era was gradually replaced by the all-digital era. The continuous signal in time and amplitude became a sampled and quantized signal, discrete in time and amplitude. This migration has been made possible by the emergence of complex electronic components (analog/digital converter, digital/analog converter, microprocessor, microcontroller) which have enabled calculations previously performed in analog to be transposed into digital form. A signal, whatever its nature (data, video, audio), can be digitized and processed using algorithms. These algorithms are either generic (recording, storage, copying, encryption and transport) or specific (sequencer, signal processing,...