Why complex number generate when using iFFT?
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The inverse fast Fourier transform (iFFT) is used to generate complex numbers because it is a mathematical operation that converts frequency domain symbols into time domain signals. In optical communication systems, iFFT is required for constructing orthogonal frequency division multiplexing (OFDM) waveforms, which are used to combat inter-symbol interference caused by multipath propagation . The iFFT is also used in systems that transmit OFDM information via IFFT up-sampling components, where it simplifies filter requirements and mitigates leakage between symbols . Additionally, complex numbers are needed in mathematics for various applications, and the iFFT aids in performing complex operations involving real and imaginary numbers . Therefore, the iFFT is used to generate complex numbers in order to facilitate signal processing and mathematical calculations in different domains.
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| Papers (4) | Insight |
|---|---|
6 Citations | Complex numbers are generated when using the inverse Fast Fourier Transform (iFFT) because they involve both real and imaginary components, which are necessary for representing the frequency domain signals in the time domain. |
| The inverse discrete Fourier transform (iFFT) used in optical OFDM waveform construction produces complex values due to the nature of the mathematical operation. | |
Patent 09 Mar 2006 26 Citations | Complex numbers are generated when using iFFT because the input samples are multiplied by complex phase factors before performing the iFFT. |
| The paper does not mention why complex numbers are generated when using iFFT. |
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