How can I add a shifted version of a signal to the original signal?

I have a complex signal x of size (1,4096), I want to add another signal y which is the shifted version of x by 0.3. I am working on signals in frequency domain here. I tried delayseq() function but did not give me a shifted sequence it just overlaps on x. Could you tell me another way of delaying or advancing or shifting x???

[Rishabh Rathore]

Delaying a signal does not change the frequencies that are present in the signal and since your signal is in frequency domain, you observe the overlap of the initial signal and the shifted signal. Try converting your signal to time domain then shift the signal and add. Then convert the resulting time domain signal to frequency domain. This way you should be able to observe the change.

Answer 1

[Honglei Chen]

Can you clarify why the result of delayseq() does not satisfy your needs? Thanks.

[Kaviya Baiju Thoppil]

Thank you for your replies. Delayseq() gives me a result that is not time shifted in frequency or time domain. I tried applying the function in time domain adding it and converting it back to the frequency domain. I will attach a figure of the signal i get you can clearly see there is no time shift. Is there any other way to shift a signal and add it to the original signal?

 Ts=8e3;
p=ifft(ifftshift(qomega));
y=delayseq(p,rmsspectralwidth,Ts);
delay_signal=fftshift(fft(y+p));
plot(fs,[abs(qomega);abs(delay_signal)]);
legend

[Honglei Chen]

I don't understand, you are plotting two spectrums. If you a delaying a signal, that doesn't change the spectrum magnitude.