Side
(x1 ja x2 vaheline erinevus
on väiksem kui x1 või x2 ise).
Sigma-delta modulatsioon on meetod analoogsignaali moduleerimiseks
digitaalsignaaliks. Samuti ka kõrgresulutsiooniliste digitaalsignaalide muundamiseks
madalresulutsioonilisteks digitaalsignaalideks (osana analoogsignaali
digitaalsignaaliks moduleerimisest).
In a conventional ADC, an analog signal is integrated, or sampled, with a sampling
frequency and subsequently quantized in a multi-level quantizer into a digital signal.
This process introduces quantization error noise. The first step in a delta-sigma
modulation is delta modulation. In delta modulation the change in the signal (its
delta) is encoded, rather than the absolute value. The result is a stream of pulses,
as opposed to a stream of numbers as is the case with PCM. In delta-sigma
modulation, the accuracy of the modulation is improved by passing the digital
annaabi.ee 
