What is pre-emphasis and receive equalization?
Transmit pre-emphasis, is a method used to boost the high-frequency content of the output signal relative to the DC signal amplitude. This boost in high-frequency content serves to effectively compensate for the frequency dependent loss the signal incurs as it propagates to the receiver. A transmit pre-emphasis is used to overcome the high frequency attenuation in the connectors and trace. Another method, receive equalization, is a function applied at the receiver intended to counteract the degradation of signal strength over a long transmission line or cable run. In demanding applications that exhibit a large signal loss it may be necessary to combine transmit pre-emphasis and receive equalization for effective high-speed communication.
