Pairwise Optimized Constellation Clustering for Optical Signal Efficiency

The patent applies preliminary action by pre-optimizing the signal constellation geometry and bit mapping before transmission. The pairwise optimization process pre-calculates the optimal constellation points and Gray-mapping assignments, so that when data is transmitted, the receiver can directly benefit from the improved Euclidean distance and Gray-mapping properties without real-time computation. This resolves the contradiction by preparing the optimization in advance, making the complex optimization work done before transmission rather than during reception.

The patent transitions from conventional 2D QAM constellations to multi-dimensional constellations by incorporating additional dimensions such as polarization states. This dimensional expansion allows for larger Euclidean distances between signal points while maintaining spectral efficiency, directly improving receiver sensitivity. The multi-dimensional approach resolves the contradiction by adding spatial dimensions to increase separation between constellation points, thereby improving reliability without proportionally increasing complexity.

The patent applies segmentation by dividing the multi-dimensional constellation optimization into manageable components. The optimization process segments the constellation into multiple sub-constellations or layers, each optimized independently for specific dimensions (e.g., amplitude, phase, polarization). This segmentation allows the complex multi-dimensional optimization problem to be broken down into simpler sub-problems, improving spectral efficiency while controlling digital signal processing complexity through modular optimization approaches.

The patent utilizes parameter changes by systematically varying constellation parameters such as point spacing, angular separation, and polarization state assignments during the optimization process. The pairwise optimization algorithm iteratively adjusts these parameters to maximize spectral efficiency while maintaining acceptable complexity. By changing parameters in a controlled, iterative manner rather than optimizing all parameters simultaneously, the patent achieves high spectral efficiency with manageable computational complexity.

The patent applies preliminary action by pre-establishing Gray-mapping encoding schemes during the constellation optimization phase. The pairwise optimization process simultaneously optimizes both the geometric arrangement of constellation points and their binary label assignments, ensuring that adjacent constellation points differ by only one bit. This preliminary setup of Gray-mapping eliminates the need for complex real-time encoding at transmission or decoding at reception, resolving the contradiction by preparing the optimal mapping in advance.

The patent introduces an intermediary optimization process that acts as a mediator between constellation geometry and bit mapping. The pairwise optimization algorithm serves as an intermediary that coordinates the assignment of binary labels to constellation points, ensuring Gray-mapping properties are satisfied while maintaining optimal geometric separation. This intermediary optimization step resolves the contradiction by mediating between the simplicity of direct mapping and the performance benefits of Gray-mapping, achieving both through coordinated optimization.