[SOLVED] Why is there distortion in real time when we are sampling at such high speeds ?

[jeffrey samuel]

i learnt that the sampling rate must be greater than or equal to twice the maximum frequency of the transmitted signal

if so why is there distortion in real time when we are sampling at such high speeds there is no point of the op to get distorted why
and what causes it

 

[not-a-moderator]

Re: sampling rate question

What you have learned is that Nyquist rate is the minimum sampling rate required to avoid aliasing, equal to twice the highest frequency contained within the signal..
The term aliasing usually refers to the case where some original frequency components have aliases below Nyquist. That often causes distortion when a continuous function is subsequently reconstructed from samples.
When attainable filters are used, some degree of oversampling is necessary to accommodate the practical constraints on anti-aliasing filters.
Thus, frequencies close to the Nyquist frequency may be distorted in the sampling and reconstruction process, so the bandwidth should be kept below the Nyquist frequency by some margin (frequency headroom) which depends on the actual filters used.

 

[jeffrey samuel]

Re: sampling rate question

if the design of the filter is inadequate there will be a large loss of data and so we are using a small BW gap in the head room area then am i right

 

[not-a-moderator]

Re: sampling rate question

Yes, you are.

Thus make sure the filter in your design is adequate.

 

[jeffrey samuel]

Re: sampling rate question

my man awesome help i think that was it i had trouble and put you put me out of it

thanks again