Recovering data from quadrature phase shift keying modulated optical signals

US9698914B2 · kind B2 · utility

Assignee

• ZTE CORPORATION · CN

Inventors

• Jianjun Yu · Princeton, US
• Junwen Zhang · Shanghai, CN

Key dates

• Filing date: Mar 28, 2014
• Grant date: Jul 4, 2017
• Expiry date: Mar 28, 2034

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04L2025/03636
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

Systems, devices and techniques for processing received QPSK modulated optical signals include sampling the received signal at twice the baud rate, thereby producing samples that are then processed as 9-QAM symbols using a decision directed least squares optimization method. A third stage of channel equalization is filtering performs channel equalization to mitigate linear filtering effects along the transmission link. Data bits are then recovered from the resulting symbol estimates. The received optical signal may also include dual polarized signals for increased bandwidth capacity.