Patent Number: 8,879,922

Title: System, method and apparatus for high-sensitivity optical detection

Abstract: An apparatus receives data encoded in a format where information bits for transmission are mapped into symbols each carrying a plurality of bits, some of which are encoded through a frequency-shift keyed (FSK) format and the rest of which are encoded through an additional modulation format on at least one FSK carrier. The receiver detects the signal through a dual-polarization coherent receiver front-end, and recovers polarization components of the signal by decoding a first non-zero portion of a plurality of bits carried by a symbol based on frequency slot position of at least one FSK carrier in the polarization components and a second non-zero portion of the plurality of bits carried by the symbol based on the additional modulation carried by at least one FSK carrier in the polarization components. Pilot-assisted orthogonal frequency-division de-multiplexing (PA-OFDM) may be used for spectrally-efficient signal reception, even in the presence of severe FSK errors.

Inventors: Liu; Xiang (Marlboro, NJ), Chraplyvy; Andrew Roman (Matawan, NJ), Tkach; Robert William (Little Silver, NJ)

Assignee: Alcatel Lucent

International Classification: H04B 10/00 (20130101)

Expiration Date: 2019-11-04 0:00:00