Ch Frequency Response (Low | Mid | High Band) (MB-OFDM)
The Low | Mid | High Band trace shows the frequency response for the corresponding Low | Mid | High Band in which the equalizer is correcting. To see a trace with all Low, Mid, and High Bands combined, see Composite Ch Frequency Response.
The per band results are computed when performing TFI/TFI2 analysis when Frequency Hopping Analysis is NOT set to Force FFI.
is computed as the reciprocal of the equalizer frequency response. The contains one complex value for each subcarrier plus an interpolated value for the middle unused subcarrier (a total of 123 values). The equalizer frequency response is normally estimated from the Channel Estimation Sequence portion of the OFDM Orthogonal Frequency Division Multiplexing: OFDM employs multiple overlapping radio frequency carriers, each operating at a carefully chosen frequency that is Orthogonal to the others, to produce a transmission scheme that supports higher bit rates due to parallel channel operation. OFDM is an alternative tranmission scheme to DSSS and FHSS. preamble.
This is similar to, but not the same as, the Digital Demod . The differences are:
Digital Demod computes this by comparing the and data, MB-OFDM demodulation computes it from the preamble/data of the burst.
Digital Demod typically uses a running average to average multiple scans when computing the equalizer frequency response. MB-OFDM demodulation does not average but computes a new equalizer response for each burst.
The equalization filter is inherent to MB-OFDM Demodulation, it cannot be enabled/disabled like in Digital Demod.
See Also
