Ch 4 Digitizer

What does the term digital mean

In form of discrete numbers

Digital signal processing

Mathmatecial manipulation of numbers representing echoes

What does the term analog mean

Proportional

In the instrument the echo voltage has been

Proportional to echo pressure

After ADC echo voltages are

Replaced by a series of numbers and further manipulation of the echoes is accomplished as digital scan processing

What does ADC convert?

The voltage form analog to digital form, also called digitizer

Interrogation rate must be?

Twice the highest frequency involved zin the interrogated voltage to preserve all the harmonics contained in the interrogated voltage

What does the ADC interrogate and determine ?

interrogates the incoming voltage at regular intervals and determines its value at each interrogation instant