Models a feed-forward equalizer
SerDes Toolbox / Datapath Blocks
The FFE block applies a feed-forward equalizer (FFE) as a symbol-spaced finite-impulse response (FIR) filter to a sample-by-sample input signal or an impulse response vector input signal. This filtering reduces distortions due to channel loss impairments.
WaveIn— Input baseband signal
Input baseband signal. The input signal can be a sample-by-sample signal specified as a scalar, or an impulse response vector signal.
WaveOut— Filtered channel output
Filtered channel output. If the input signal is a sample-by-sample signal specified as a scalar, the output is also scalar. If the input signal is an impulse response vector signal, the output is also a vector.
Mode— FFE operating mode
FFE operating mode:
Off — FFE is bypassed and the input
waveform remains unchanged.
Fixed — FFE applies the FFE tap
weights specified in Tap weights to input waveform.
get_param(gcb,'Mode') to view the current FFE
set_param(gcb,'Mode',value) to set FFE to a specific
Tap weights— FFE tap weights
[0,1,0,0,0](default) | row vector
FFE tap weights, specified as a row vector in volts. The length of the vector specifies the number of taps. The vector element value specifies the strength of the tap at that element position. The tap with the largest magnitude is the main tap and therefore defines the number of pre- and post-cursor taps.
You can use a valid MATLAB expression to evaluate the Initial tap weights (V) row vector.
set_param(gcb,'TapWeights',"zeros[(1,4) 1 zeros(1,15)]")
creates an FFE with 20 taps where the fifth tap is the main tap.
get_param(gcb,'TapWeights') to view the current FFE
set_param(gcb,'TapWeights',value) to set FFE to a
specific Tap weights vector.
Normalize— Normalize tap weights
Select to normalize tap weight vectors so that the sum of the absolute values of the Tap weights vector elements is one.
Visualize Response— Plot FFE FIR filter response
Click to plot the response of the FFE FIR (finite impulse response) filter.
Mode— Include Mode parameter in IBIS-AMI model
Select to include Mode as a parameter in the IBIS-AMI file. If you deselect Mode, it is removed from the AMI files, effectively hard-coding Mode to its current value.
Tap weights— Include Tap weights parameter in IBIS-AMI model
Select to include Tap weights as a parameter in the IBIS-AMI file. If you deselect Tap weights, it is removed from the AMI files, effectively hard-coding Tap weights to its current value.