Receiver for high rate digital communication system
View Patent ↗A system and method for processing received transmission signal(s) adapted to be used in high rate communication systems without impairing the received signal energy and without additional expensive components. The system and method are adapted to transmission system(s) having at the receiver-side a compound system of a feed-forward equalizer (FFE) and a subsequent decision feedback equalizer (DFE). A feed forward equalization and/or a decision feedback equalization is performed on the received high rate signal by deriving adaptation information from the equalized signal after a signal decision is performed for adjusting all intended feed forward equalization and/or decision feedback equalization coefficients and/or table entries in dependence on said information.
1. A method of processing a received transmission signal adapted for the use within a high rate communication system, wherein the method comprises the steps of:
performing on the received signal a feed forward equalization and a decision feedback equalization by
deriving information from the equalized signal after a signal decision is performed,
adjusting intended feed forward equalization coefficients and decision feedback equalization coefficients or table entries depending on said information,
further comprising the steps of performing a forward error correction on said equalized signal, generating control values in dependence on symbols of the equalized signal prior to said error correction and symbols of the corrected signal at defined time instants,
further comprising the step of adapting each equalization coefficient or table entry in dependence on a respective previous equalization coefficient or table entry and on said control values, in particular based on a selectable adaptation step size parameters,
and further comprising adjusting an appropriate time delay for ensuring a maximum average agreement of corrected symbols and decided output symbols at defined time instants.
2. The method of claim 1 , further comprising the steps of deriving digital adaptation information periodically at definable time instants and feeding back said information for adaptively adjusting intended feed forward equalization coefficients and/or decision feedback equalization coefficients or table entries simultaneously.
3. A method as claimed in claim 1 , wherein the transmission signal comprises an error or channel coding information and wherein the method further comprises the step of performing an error rate evaluation based on said coding information for generating control values for adjusting the intended feed forward equalization coefficients and/or decision feedback equalization coefficients or table entries depending on said information.
4. A method as claimed in claim 1 wherein linear and/or non-linear equalization coefficients are adjusted.
5. A receiver for a high rate communication system, comprising a feed forward equalizer and a decision feedback equalizer with said equalizer(s) connected to a signal detection device having
means for receiving a transmission signal,
means for deriving information from the transmission signal after said signal detection device,
updating means for adjusting all intended feed forward equalization coefficients and decision feedback equalization coefficients or table entries in dependence on said information,
further comprising means for decoding digital symbol after said decision feedback periodically at definable time instants, and mean for performing an error rate evaluation based on channel or error coding information embedded within the transmission signal, and means for generating adaptation control values using said error rate evaluation,
further comprising means for performing a forward error correction, means for generating adaptation control values in dependence on corrected symbols and decided detection device output symbols at defined time instants, and means for adapting each intended equalization coefficient or table entry in dependence on the respective previous equalization coefficient or table entry and on said control values, in particular based on a selectable adaptation step size parameter,
and further comprising means for adjusting an appropriate time delay for ensuring a maximum average agreement of corrected symbols and decided output symbols at defined time instants.