# Nyquist formula for digital communication

1. ## Nyquist formula for digital communication

Hi people,

It would be amazing if some one could help me understanding this ?

Just to let you know, I know Nyquist sampling theory and I know that the sampling frequency should be higher than 2 times max frequency of band in order to avoid ISI.

But I cannot not relate it to BPS ? and what is the relationship with sampling ?

In modulation we have a pulse train (or Sinc train) and we have its spectrum (Rect or Sinc). we do up conversion and move this BW to upper frequencies. What is the sampling issue here I dont get it.

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2. ## Re: Nyquist formula for digital communication

Bits Per Second rate is the product of the rate of samples per second and bits per sample.

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3. ## Re: Nyquist formula for digital communication

thank you for reply but those you mentioned are all related to ADC not data transmission part.

rate of samples is basically sample and hold clock.
bits per sample is ADC output bit size.

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4. ## Re: Nyquist formula for digital communication

In communications it is also true that bits/second rate = (symbols/second)*(bits/symbol).

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