Guard Interval (802.16 OFDM)
: 1/4 (See 802.16 OFDM Standard Setups/Presets Table.)
: 0-1
The is the ratio of the Cyclic Prefix "CP 1) Contention period, or 2) Cyclic prefix" time to the inverse 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. time "T(IFFT Inverse Fast Fourier Transform)". The is used to eliminates inter-symbol and inter-carrier interference. A copy of the last guard interval T(GI Guard interval) of the useful symbol period "T(IFFT)", termed Cyclic Prefix "CP", is used to collect multipath, while maintaining the orthogonality of the subcarriers. Each symbol is transmitted for a slightly longer time, extended symbol time T(s), than the active (or useful) symbol time T(IFFT). The extra time is the .
The following selections are provided:
- (default)
- : Allows Guard Interval values between 0 to 1 to be entered.
The Guard Interval time period T(GI)is specified as a fraction (percentage) of the inverse FFT time period T(IFFT).
Guard Interval (TGI)Time Calculation
The Guard Interval (TGI) Time Calculation is dependent on the nominal bandwidth value selected.
OFDM Frame and the Guard Interval
See Also
