DECISION FEEDBACK EQUALIZER WITH MAXIMUM-LIKELIHOOD SEQUENCE ESTIMATION

摘要

PURPOSE: A decision feedback equalizer with a maximum-likelihood sequence estimation is provided to improve the capacity of a decision feedback equalizer by reducing an error in a delay line. CONSTITUTION: The first addition node(12) comprises the first input(+) for receiving an input signal and the second input(-) for receiving the second feedback signal. A maximum-likelihood sequence estimator(14) has an input connected with an output of the first addition node(12) and receives a signal(data_in). The maximum-likelihood sequence estimator(14) estimates a symbol sequence. The second addition node(16) comprises the first input(+) connected with the output of the first addition node(12) and the second input(-) for receiving the first feedback signal. A signal level decoder(18) has an input connected with the output of the second addition node(16) and an output. A delay line(20) has a multitude of the first tap for generating the first tap signals according to the first tap coefficient and a multitude of the second tap for generating the second tap signals according to the second tap coefficient. The first addition circuit(22) generates the first feedback signal by adding the first tap signals. The second addition circuit(24) generates the second feedback signal by adding the second tap signals. An error signal generator(26) has the first input(+) connected with an input of the signal level decoder(18) and the second input(-) connected with an output of the signal level decoder(18).