ARMA GUY <arma_ann@yahoo.com> wrote:
 
> I have a set of noiseless data , x= [1 2 3 4 5 6 ].
 
> I want to add noise to it using 
 
> g= x+ 0.5* rand(1,6)
 
> How do i calculate the signal to noise ratio of this signal if the

You know the amplitude of the noise, now you need the amplitude
of the signal.  (power would be more usual.)

You have to decide what the signal actually should look like.
You might compute the RMS amplitude, but you have to 
know where zero is.   Do you subtract the average (DC) value
before computing the amplitude?  Your choise.

-- glen

On the second scenario, no information was given except the data and the
words, " it contains noise" , how do i find the SNR ?

Thanks,

>On 30 Jan, 09:56, "ARMA GUY" <arma_...@yahoo.com> wrote:
>> Suggestion needed
>>
>> I have a set of noiseless data , x= [1 2 3 4 5 6 ].
>>
>> I want to add noise to it using
>>
>> g= x+ 0.5* rand(1,6)
>>
>> How do i calculate the signal to noise ratio of this signal if the
>> variance of the noise is 0.5.I know the relationship between SNR and
>> variance, mathematicallly and can implement that in MATLAB. Is there
any
>> inbuilt function that can calculate that easily ?
>
>How would you implement this yourself the 'non-easy' way?
>
>> The second scenario is that i have a signal
>>
>> d= [ 5 6 7 8 9], no other information than the signal contains noise.
How
>> do i get the SNR of this signal.
>
>Separate the noise from the signal and apply the SNR formula.
>
>Rune
>

On 30 Jan, 09:56, "ARMA GUY" <arma_...@yahoo.com> wrote:
> Suggestion needed
>
> I have a set of noiseless data , x= [1 2 3 4 5 6 ].
>
> I want to add noise to it using
>
> g= x+ 0.5* rand(1,6)
>
> How do i calculate the signal to noise ratio of this signal if the
> variance of the noise is 0.5.I know the relationship between SNR and
> variance, mathematicallly and can implement that in MATLAB. Is there any
> inbuilt function that can calculate that easily ?

How would you implement this yourself the 'non-easy' way?

> The second scenario is that i have a signal
>
> d= [ 5 6 7 8 9], no other information than the signal contains noise. How
> do i get the SNR of this signal.

Separate the noise from the signal and apply the SNR formula.

Rune

Suggestion needed

I have a set of noiseless data , x= [1 2 3 4 5 6 ].

I want to add noise to it using 

g= x+ 0.5* rand(1,6)

How do i calculate the signal to noise ratio of this signal if the
variance of the noise is 0.5.I know the relationship between SNR and
variance, mathematicallly and can implement that in MATLAB. Is there any
inbuilt function that can calculate that easily ?

The second scenario is that i have a signal

d= [ 5 6 7 8 9], no other information than the signal contains noise. How
do i get the SNR of this signal.