2018 Fiscal Year Final Research Report
Design and Implementation of Si-based Optical Discrete Fourier Transformer
| Project/Area Number |
16K06345
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Multi-year Fund |
|---|
| Section | 一般 |
|---|
| Research Field |
Communication/Network engineering
|
|---|
| Research Institution | University of Yamanashi |
|---|
Principal Investigator |
|
|---|
| Research Collaborator |
KODAMA Takahiro
|
|---|
| Project Period (FY) |
2016-04-01 – 2019-03-31
|
| Keywords | 光符号分割多重 / 光離散フーリエ変換器 / シリコン光チップ |
|---|
| Outline of Final Research Achievements |
This research aimed to implement optical discrete Fourier transformers (ODFT) for optical code division multiplexing (OCDM). Four-chip ODFT's were designed and implemented on Si-substrates and characterized. The coupling loss of the Si-substrates were 20 dB and the extinction ratio of the ODFT was 5.8 dB in this trial. At the same time, numerical evaluations on downsizing optical delay lines based on photonic crystal waveguides (PCW) and compensation of amplitude slope due to loss of optical delay lines were performed. By incorporating a specially designed charp-rod structure the coupling loss between a Si-nano wire and a PCW was estimated around 1.0 dB comparing with 5.9 dB without the chirp structure. Also the digital compensation of the amplitude slope resulted in 0.3 dB improvement in power penalty.
|
| Free Research Field |
光通信システム
|
| Academic Significance and Societal Importance of the Research Achievements |
OCDM 方式は，符号器・復号器に光ファイバ型回折格子や石英導波路などのこれまでの実装技術では，伝送速度の向上に限界がきている．研究代表者はこれまでに，フーリエ符号化の導入，多値変調方式の導入，ディジタルコヒーレント光受信技術の導入などで本方式のブラッシュアップを行ってきたが，この結果，特に多値変調信号の導入には，従来よりも格段に高精度な符号器・復号器が必要であることが明らかになっている．本課題で，Si 基板型符号器・復号器を実現することで高精度を図り，伝送速度の向上を目指した．
|
