ローカル星座分解ジョイントシェーピングに基づく超高次QAM変調アプローチ
Optics express
|December 19, 2025
まとめ
本研究は、デルタシグマ変調(DSM)を用いた強度変調直接検出(IMDD)システムにおけるビット誤り率(BER)性能を向上させる、超高次直交振幅変調(QAM)信号のための新しいジョイントシェーピングスキームを導入する。この手法は、受信機感度とシステム効率を向上させる。
背景:
- データレートを増加させるためには、超高次直交振幅変調(QAM)が不可欠である。
- 既存の方法では、強度変調直接検出(IMDD)システム用の複雑な星座を効率的にシェーピングする際に課題が生じている。
- 確率的シェーピング(PS)と幾何学的シェーピング(GS)は、星座最適化のための高度な技術である。
結論:
- ローカル星座分解ジョイントシェーピングスキームは、IMDDシステムにおける超高次QAM信号の最適化のための優れた方法を提供する。
- PS、GS、およびDSMの統合は、BER性能と受信機感度を効果的に向上させる。
- このアプローチは、将来の高容量光通信システムにとって重要な進歩を表す。
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