Ch Frequency Response (802.11b/g DSSS/CCK/PBCC)

When 802.11b/g DSSS Direct sequence spread spectrum. The data transmission scheme (sometimes referred to as a "'modulation" scheme) used in 802.11b WLANs. DSSS uses a radio transmitter operating at a fixed centre frequency, but using a relatively broad range of frequencies, to spread data transmissions over a fixed range of the frequency band. 802.11a and 802.11g (when not operating in 802.11b mode) use Orthogonal Frequency Division Multiplexing (OFDM)./CCK complementary code keying/PBCC packet binary convolutional code Demodulation is enabled and the equalizer is ON, the Ch Frequency Response trace shows the frequency response of the channel for which the equalizer is correcting. Ch Frequency Response is computed as the inverse of the equalization filter's frequency response. The data is complex and is normally displayed in units of magnitude, phase, or group delay.

Frequency Span

The Ch Frequency Response is shown with a bandwidth equal to the Chip Rate, because it is computed from one point per chip data. Because of aliasing, it may not accurately reflect the true channel frequency response.

For further details, see Using Equalization.