Hello,
until now i don't have a response for my question, thanks to the person
who wanted help me.
>signal wrote:
>> Jerry,
>> Please, could you explain more, above i writted my method.
>> thanks
>>
>>
>>
>>>signal wrote:
>>>
>>>>Hello,
>>>>
>>>>when I plotted two curves, I mean xcorr and rxy , I found same pace,
>>
>> but
>>
>>>>one of the curves is shifted and out of phase with an angle of 180
>>>>compared to the other
>>>
>>>Perhaps, along the way, you missed an odd number of minus signs.
>
>My remark was intended to me a humorous way to point out that a
>180-degree phase shift and a negation are the same. I'm sorry that the
>joke fell flat.
>
>Jerry
>--
>Engineering is the art of making what you want from things you can get.
>�����������������������������������������������������������������������
>
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Reply by Jerry Avins●June 30, 20052005-06-30
signal wrote:
> Jerry,
> Please, could you explain more, above i writted my method.
> thanks
>
>
>
>>signal wrote:
>>
>>>Hello,
>>>
>>>when I plotted two curves, I mean xcorr and rxy , I found same pace,
>
> but
>
>>>one of the curves is shifted and out of phase with an angle of 180
>>>compared to the other
>>
>>Perhaps, along the way, you missed an odd number of minus signs.
My remark was intended to me a humorous way to point out that a
180-degree phase shift and a negation are the same. I'm sorry that the
joke fell flat.
Jerry
--
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������
Reply by signal●June 30, 20052005-06-30
Jerry,
Please, could you explain more, above i writted my method.
thanks
>signal wrote:
>> Hello,
>>
>> when I plotted two curves, I mean xcorr and rxy , I found same pace,
but
>> one of the curves is shifted and out of phase with an angle of 180
>> compared to the other
>
>Perhaps, along the way, you missed an odd number of minus signs.
>
> ...
>
>Jerry
>--
>Engineering is the art of making what you want from things you can get.
>�����������������������������������������������������������������������
>
This message was sent using the Comp.DSP web interface on
www.DSPRelated.com
Reply by Jerry Avins●June 30, 20052005-06-30
signal wrote:
> Hello,
>
> when I plotted two curves, I mean xcorr and rxy , I found same pace, but
> one of the curves is shifted and out of phase with an angle of 180
> compared to the other
Perhaps, along the way, you missed an odd number of minus signs.
...
Jerry
--
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������
Reply by signal●June 30, 20052005-06-30
Hello,
when I plotted two curves, I mean xcorr and rxy , I found same pace, but
one of the curves is shifted and out of phase with an angle of 180
compared to the other
>Hi,
>thanks for your response.
>This is a typing error, i used sxy=xx.*conj(yy).
>
>
>>signal wrote:
>>> Sxy=xx.*conj(y);
>>
>>Should that be Sxy=xx.*conj(yy);
>>
>>??
>>
>>--
>>Jim Thomas Principal Applications Engineer Bittware, Inc
>>jthomas@bittware.com http://www.bittware.com (603) 226-0404 x536
>>Any sufficiently advanced technology is indistinguishable from magic.
>> - Arthur C. Clarke
>>
>
>
>
>This message was sent using the Comp.DSP web interface on
>www.DSPRelated.com
>
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Reply by signal●June 30, 20052005-06-30
Hi,
thanks for your response.
This is a typing error, i used sxy=xx.*conj(yy).
>signal wrote:
>> Sxy=xx.*conj(y);
>
>Should that be Sxy=xx.*conj(yy);
>
>??
>
>--
>Jim Thomas Principal Applications Engineer Bittware, Inc
>jthomas@bittware.com http://www.bittware.com (603) 226-0404 x536
>Any sufficiently advanced technology is indistinguishable from magic.
> - Arthur C. Clarke
>
This message was sent using the Comp.DSP web interface on
www.DSPRelated.com
Reply by signal●June 30, 20052005-06-30
Hi,
thanks for your response.
This is a typing error, i used sxy=xx.*conj(yy).
>signal wrote:
>> Sxy=xx.*conj(y);
>
>Should that be Sxy=xx.*conj(yy);
>
>??
>
>--
>Jim Thomas Principal Applications Engineer Bittware, Inc
>jthomas@bittware.com http://www.bittware.com (603) 226-0404 x536
>Any sufficiently advanced technology is indistinguishable from magic.
> - Arthur C. Clarke
>
This message was sent using the Comp.DSP web interface on
www.DSPRelated.com
Reply by Jim Thomas●June 30, 20052005-06-30
signal wrote:
> Sxy=xx.*conj(y);
Should that be Sxy=xx.*conj(yy);
??
--
Jim Thomas Principal Applications Engineer Bittware, Inc
jthomas@bittware.com http://www.bittware.com (603) 226-0404 x536
Any sufficiently advanced technology is indistinguishable from magic.
- Arthur C. Clarke
Reply by Martin Eisenberg●June 30, 20052005-06-30
signal wrote:
> Sxy=xx.*conj(y);
Sxy=xx.*conj(yy);
Reply by Rune Allnor●June 30, 20052005-06-30
I don't have xcorr available, so I don't know the detail of
how it works, but here are some suggestions of what to look
for.
> I used xcorr to calculate cross correlation in matlab, i tried to do the
> same thing by using fft, so :
> i have 2 signals x, y
> L=max(lenght(x), lenght(y))
Make sure to use the signal the same length as xcorr does.
I wouldn't be surprised if it is something along the lines of
L=length(x)+2*(length(y)-1);
> xx=fft(x,2*L).
> yy=fft(y,2*L).
Make sure to use the same FFT length as xcorr does. Again,
I wouldn't be surprised if it is something along the lines of
Nfft = length(x)+2*(length(y)-1);
Remember, no symmetry can be expected for cross correlation.
> Sxy=xx.*conj(y);
Could it be that the order of the conjugates are different?
> rxy=fftshift(real(ifft(Sxy))) ;
Does xcorr shift the data so that zero lag ends up in the middle?
If so, how does it handle the different lengths of x and y?
> Rxy is my cross correlation,the problem is when i drawed rxy and
> xcorr(x,y)