A High Speed Transmitter Dynamic Equalization Method for Serial Links

Radio engineering

Аннотация

A method for signal equalization of high speed serial links transmitter is presented in this paper. To avoid signal losses and ISI effects besides receiver input signal equalization, transmitter output signal pre-equalization is also needed right before transmission. One of the known methods is pre/post emphases with constant gains, which provides pre-equalization independent of frequency. The disadvantage of this method is frequency independency which means that the signal will propagate through the channel with pre-equalized high frequency regions but independent on the data rate. To validate the proposed architecture, experiments are conducted for example, with various injected faults, for which the conventional approach of examining the eye opening at the output of the equalizer results. When data signals in the inputs of receiver come with high frequencies without equalizer and with many low and high frequency harmonics, the output system can lose the data, because high frequencies of the data can be rejected by the channel. One of the main reasons of signal rejection by the channel is the low pass filter and it can filter high frequency data signals. That’s why in high speed serial links some data transferring and receiving process support blocks are used which provide signal reliable reading and help to avoid data errors and loss.

The proposed transmitter equalization mechanism can be used in the high speed input/output standards such as Universal Serial Bus (USB) which provides pre-equalization depending on a data rate