FFT Length (802.16 OFDMA)

Default: FFT Fast Fourier Transform: A mathematical operation performed on a time-domain signal to yield the individual spectral components that constitute the signal. See Spectrum. 1024 (See OFDMA Standard Presets Table.)

Range: 128,1024, 1024, 2048

The FFT Length parameter specifies the FFT size.

is only available when the Restrict bandwidth to standard values check box on the tab is cleared.

OFDMA supports a scalable frame structure where the FFT size scales with bandwidth to keep the subcarrier spacing fixed. The OFDMA standard specifies four FFT "NFFT"sizes: 128, 512, 1024 and 2048.