Patent ID: 8538278

Claim:
A polarization multiplexing, optical receiver comprising: a training/data recovery module configured to extract superimposed training signals and data signals from a plurality of orthogonally polarized signals such that training signals and data signals may be used on a single channel without loss of spectral efficiency, comprising: a channel response estimation module which estimates a channel response based on the mean of each orthogonally polarized signal; and a linear minimum mean-square error equalization module configured to distinguish a data sequence from a training sequence in each orthogonally polarized signal based on the respective channel response estimate; wherein said channel response estimation includes a channel estimation responsive to Ĥ k =(C k H C k ) −1 C k H {circumflex over (D)} k where Ĥ k is the vector of the channel estimates, {circumflex over (D)} k is the vector of the {circumflex over (d)} mk 's. {circumflex over (d)} mk is a function of a received signal and is based on d ^ mk = 1 T ⁢ ∑ n = 0 T - 1 ⁢ ⁢ y ⁡ ( n ) ⁢ ⅇ - jα mk ⁢ n . where H shown as a superscript of C k indicates that C k H is a Hermitian transpose of C k , and an iterative updating of a multi-polarization channel keeps repeating until reaching the point where the incremental difference between two successive estimates of the multi-polarization channel reaches a predefined threshold.