Improvement of contrast ratio in quadriphase-shift-keying optical label recognition with passive optical waveguide circuit

Hiroki Kishikawa; Yoshihiro Makimoto; Kensuke Inoshita; Sanae Igarashi; Nobuo Goto M.D.; Shin-ichiro Yanagiya

doi:10.1117/1.OE.55.5.057104

31 May 2016 Improvement of contrast ratio in quadriphase-shift-keying optical label recognition with passive optical waveguide circuit

Hiroki Kishikawa, Yoshihiro Makimoto, Kensuke Inoshita, Sanae Igarashi, Nobuo Goto M.D., Shin-ichiro Yanagiya

Author Affiliations +

Optical Engineering, Vol. 55, Issue 5, 057104 (May 2016). https://doi.org/10.1117/1.OE.55.5.057104

Abstract

In photonic label routing networks, recognition of optical labels is one of the key functions. We have proposed waveguide-type optical circuits for recognition of optical labels encoded in quadriphase-shift-keying (QPSK) form. A basic device for the circuits consists of a 3-dB directional coupler, two Y-branches, and an asymmetric X-junction coupler. We employed a scheme of complete interference of optical waves between each coded pulse and a reference pulse in our previously reported paper. The contrast ratio of the output at the destination output port to the outputs at the other ports was reported to decrease to 1.6, 1.28, and 1.13 for two-, three-, and four-stage circuits for recognition of 16, 64, and 256 QPSK labels, respectively. We find optimum circuits with improved contrast ratio of 1.8, 1.6, and 1.47 for 16, 64, and 256 labels, respectively. The recognition operation with the improved circuits is numerically confirmed using the beam propagation method. Noise tolerance of the proposed circuits is also clarified by numerical simulation. The improved circuits are optimum from the viewpoint of efficient use of optical power and noise tolerance.

Citation Download Citation

Hiroki Kishikawa, Yoshihiro Makimoto, Kensuke Inoshita, Sanae Igarashi, Nobuo Goto M.D., and Shin-ichiro Yanagiya "Improvement of contrast ratio in quadriphase-shift-keying optical label recognition with passive optical waveguide circuit," Optical Engineering 55(5), 057104 (31 May 2016). https://doi.org/10.1117/1.OE.55.5.057104

Published: 31 May 2016

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available