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Updated: Sep 9, 2025

12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
17.1K
マイクロウェーブトーンのアンプリチュード・ノイズキャンセル
Joe Depellette1, Ewa Rej1, Matthew Herbst1
1QTF Centre of Excellence, Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland.
The Review of scientific instruments
|August 28, 2025
まとめ
マイクロウェーブ発電機の振幅騒音を 減らすためのフィードバック・キャンセリング技術を開発しました 微波光学のような実験では 感度が向上します
科学分野:
- 物理学
- 実験物理学
- 量子現象について
背景:
- 一貫したトーン,特に振幅のノイズは,敏感性を制限し,敏感な実験システムで加熱を引き起こす.
- 振幅のノイズが優位である場合,既存のフェーズ・ノイズ・キャンセリング技術は無効である.
- 振幅ノイズは,相ノイズの性能が向上するにつれて,マイクロ波システムにおける懸念が高まっている.
研究 の 目的:
- マイクロウェーブ発電機からの振幅ノイズをフィードバック・キャンセリングを用いて減らすための新しいテクニックを提示する.
- この技術の有効性を 顕微波光学実験で実証する
主な方法:
- フィールドプログラム可能なゲート配列 (FPGA) を使用して,調整可能な増強と時間遅延でキャンセルノイズ信号を生成します.
- 破壊的な干渉を元々のマイクロ波音と 発生したノイズ信号の間に実行する.
- 周波数オフセットと帯域幅のチューニング
主要な成果:
- 4GHzのマイクロ波トーンから2MHzのオフセットで13dBのノイズパワーを削減し,全ノイズをフェーズノイズレベルに低下させました.
- 微波光学実験で外から誘発された空洞加熱の3.5倍減少を観測した.
- 最低オシレータの占有率を 2 倍に下げた
結論:
- 開発されたフィードバック・キャンセリング技術は,マイクロ波発電機の振幅ノイズを効果的に軽減します.
- この方法は,マイクロ波光学におけるサイドバンド冷却などの敏感な実験の性能を高めます.
- この技術は,マイクロ波システムの改善のためのノイズキャンセリング戦略の範囲を拡大します.
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