METHOD AND APPARATUS OF PRODUCING A DIGITAL DEPICTION OF A SIGNAL

摘要

An apparatus for producing a digital depiction of a signal (10) which is adaptive to the signal itself. A constant rate sampling means, such as an analogue to digital converter (2), samples the signal (10) at a constant rate and produces a first digital depiction (12) of a signal. A transformation means (14) is responsive to the first digital depiction (12) and produces a second digital depiction based on the evolution of the signal. The transformation means may be capable of determining when a predetermined threshold level has been crossed and measuring the time interval between predetermined threshold level crossings. The transformation means (14) may include a logic arrangement and a timer counter and is run from a clock signal (16) from the same clock (6) as drives the sampling means. A method of adapting a conventional ADC (2) to adaptively sample the signal (10) by adding a transformation means (14) run off the same clock (6) as the ADC (2) is also provided.