1.4. Optimizing for Crosstalk at High Datarates
A high-speed link may suffer from near-end crosstalk at high datarates (rates greater than 17 Gbps). The higher the datarate, the more likely it is for crosstalk to contribute to a high BER. When the Transceiver Toolkit's Auto Sweep feature does not yield a satisfactory result, you must compensate for crosstalk components.
- Use TX Pre-emphasis Post-Tap 1 and RX CTLE to mitigate the crosstalk effect.
- Tune each channel sequentially with all neighboring channels disabled.
- After tuning each channel, enable all channels concurrently with the respective channels' optimized settings.
- If not all channels have acceptable BERs, evaluate each channel with the Transceiver Toolkit.
- When you run multiple concurrent channels, a crosstalk component may cause one or more (not all) channels to have a high BER. For the victim channel, repeat Optimizing Your Settings to increase the (TX) Post-Tap and (RX) CTLE until the BER is acceptable.