Time filter

Source Type

Palo Alto, CA, United States

Gorshtein A.,Ben - Gurion University of the Negev | Sadot D.,Ben - Gurion University of the Negev | Dorman G.,MultiPhy
Optical Fiber Technology | Year: 2015

A novel MIMO equalization architecture optimized for baud rate clock recovery (BCR-MIMO) in coherent 112 Gbit/sec dual polarization quadrature phase shift keying (DP-QPSK) metro systems is proposed. This architecture is designed to decouple between multiple-input-multiple-output (MIMO) equalization and clock recovery (CR) loops, avoiding the interaction between them. The decoupling between the two loops is achieved, while maintaining similar MIMO equalizer performance, as compared to the butterfly-structured equalizer. © 2015 Elsevier Inc. All rights reserved.

A method for performing blind channel estimation for an MLSE receiver in a communication channel, according to which Initial Metrics Determination Procedure (IMDP) is performed using joint channel and data estimation in a decision directed mode. This is done by generating a bank of initial metrics that assures convergence, based on initial coarse histograms estimation, representing the channel and selecting a first metrics set M from the predefined bank. Then an iterative decoding procedure is activated during which, a plurality of decision-directed adaptation learning loops are carried out to perform an iterative histograms estimation procedure for finely tuning the channel estimation. Data is decoded during each iteration, based on a previous estimation of the channel during the previous iteration. If convergence is achieved, ISI optimization that maximizes the amount of ISI that is compensated by the MLSE is performed.

System and method for digitally equalizing a data channel having wide channel impulse response for clock recovery of heavily ISI-induced received signals operating at one sample per symbol, according to which the received signal is pre-processed to provide a received signal with modified constellation, which is pre-processed for the decision process of signal with Inter-Symbol Interference by introducing controlled ISI to the received signal. The decision process is performed, based on a higher order vocabulary according to the introduced controlled ISI.

The present invention is directed to a MIMO equalization system and method, optimized for baud rate clock recovery in coherent symbol-spaced DP-QPSK Metro systems. According to this method, the Mueller & Muller timing function is extended to cope with controlled ISI induced signals, while decoupling between MIMO equalization and clock recovery loops, using a midpoint output of the equalizer for timing estimation, instead of its final output. At least a portion of controlled Inter-Symbol Interference (ISI) is kept intact and the controlled ISI is compensated by an MLSE, right after carrier timing synchronization.

A method for improving the resilience of a communication channel (such as an optical communication channel) to correlated errors (e.g., burst errors), the channel is being formed by a time-multiplexed aggregation of a plurality of lower rate constituent lanes and employs a Forward Error-Correction (FEC) mechanism for forming codewords from data carried by the constituent lanes. Accordingly, the distribution of errors among the codewords is modified by introducing, at the transmitter side, specific delays to the transmission times via the constituent lanes, relative to each other.

Discover hidden collaborations