I have a sampled time domain signal composed of a number of sinusoids and I'd like to extend it past my last sample.

I have a sampled time domain signal composed of a number of sinusoids. I have around 1700 samples, I've done an FFT to see the spectrum and I'd like to use iFFT to extend it past my last sample of the time domain signal. i.e. I have 1700 samples and I like to see what the signal looks like between 1700 - 2500 samples.

Each of the sinusoids has a different phase, so I can't just reconstruct it just from the spectrum using each frequency starting at zero radians.

I've tried to do this with just scripts, but I also have the signal processing toolbox, but I can't figure out if the signal processing package can help me to do this, or wether I can do this using scripts.

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