Takanori Sato, Ph.D.

Education

Professional Experience

Honors and Awards

Research Grants and Projects

Apr. 2019 - Mar. 2022	Japan Society for the Promotion of Science: Grant-in-Aid for Early-Career Scientists (KAKENHI)
Apr. 2017 - Mar. 2019	Japan Society for the Promotion of Science: Grant-in-Aid for JSPS Fellows (KAKENHI)

Research Interests

Association Memberships

Publications

Journal (peer-reviewed)

[] G. Ocampo, T. Sato, M. Iizuka, and K. Saitoh, “Random polarization-mode coupling effects in heterogeneous multi-core fibers with different cladding diameters,” J. Lightw. Technol., IEEE, vol. 42, no. 16, pp. 5674-5680, Aug. 2024.

[] T. Kimura, T. Sato, M. Wada, T. Mori, T. Sakamoto, R. Imada, T. Matsui, K. Nakajima, and K. Saitoh, “Design of mode-dependent-loss controller using long period fiber grating with coating material for 2LP-mode transmission system,” J. Opt. Soc. Am. B, Optica, vol. 41, No. 9, pp. 1960-1967, Aug. 2024.

[] D. A. Ando, T. Nishimura, T. Sato, T. Ohgane, Y. Ogawa, and J. Hagiwara, “Strategies for DOA-DNN estimation accuracy improvement at low and high SNRs,” Trans. Commun., IEICE, July 2024(Early Access).

[] S. Yasumori, T. Sato, K. Morimoto, T. Kawai, A. Enokihara, S. Nakajima, and A. Kanno, “Optical mode multiplexer using LiNbO3 asymmetric directional coupler enabling voltage control for phase-matching condition,” Trans. Electron., IEICE, vol. E107.C, no. 5, pp. 146-149, May 2024.

[] T. Sato, K. Maeda, Y. Sawada, T. Mitarai, T. Hiratani, T. Okimoto, T. Ishikawa, N. Fujiwara, H. Yagi, and K. Saitoh, “High tolerant design of athermal Si wavelength filter using Mach-Zehnder interferometer,” Jpn. J. Appl. Phys, vol. 63, No. 4, pp. 04SP55-1–04SP55-6, Apr. 2024.

[] K. Nakamura, T. Fujisawa, T. Sato, and K. Saitoh, “Tunable O-band high-tolerance silicon mode multiplexer based on phase-mismatched asymmetric directional couplers,” J. Opt. Soc. Am. B, OSA, vol. 41, No. 5, pp. 1106-1115, Apr. 2024.

[] K. Nakamura, T. Sato, and K. Saitoh, “A silicon mode multiplexer based on the three-stage cascaded wavelength insensitive coupler for MDM-WDM transmission system,” IEICE Electronics Express, IEICE, vol. 21, no. 7, pp. 20240065-1-20240065-6, Mar. 2024.

[] H. Wang, T. Fujisawa, T. Sato, M. Wada, T. Mori, T. Sakamoto, R. Imada, T. Matsui, K. Nakajima, and K. Saitoh, “Design of PLC E31-E13 and E-LP tapered mode converters using fast quasiadiabatic dynamics,” IEICE Electronics Express, IEICE, vol. 20, no. 23, pp. 20230392-1-20230392-6, Dec. 2023.

[] S. Yasumori, T. Sato, K. Morimoto, T. Kawai, A. Enokihara, S. Nakajima, and A. Kanno, “Electro-optic modulator with tunable multimode interference couplers based on LiNbO3 waveguides and optical single-sideband modulation,” J. Lightw. Technol., IEEE, vol. 41, no. 23, pp. 7059-7066, Dec. 2023.

[] T. Mori, T. Fujisawa, J. Sakamoto, Y. Yamashita, T. Sakamoto, R. Imada, R. Ima, T. Sato, K. Watanabe, R. Kasahara, T. Hashimoto, K. Saitoh, and K. Nakajima, “Variable mode-dependent-loss equalizer based on silica-PLC for three-mode transmission,” Opt. Fiber Technol., Elsevier, vol. 81, Art. 103547, pp. 1-7, Dec. 2023.

[] D. A. Ando, Y. Kase, T. Nishimura, T. Sato, T. Ohgane, Y. Ogawa, and J. Hagiwara, “Deep neural networks based end-to-end DOA estimation system,” Trans. Commun., IEICE, vol. E106.B, no. 12, pp. 1350-1362, Dec. 2023.

[] T. Sato, M. Wada, T. Mori, T. Sakamoto, R. Imada, T. Matsui, K. Nakajima, and K. Saitoh, “Broadband design of silica-PLC mode-dependent-loss equalizer for 2LP-mode transmission systems,” Optics Express, OSA, vol. 31, no. 24, pp. 39965-39980, Nov. 2023.

[] Z. Zhao, T. Sato, T. Fujisawa, T. Iawaya, Y. Sagae, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “Investigation of double-cladding heterogeneous step-index 2LP-mode multicore fiber with two-ring layout,” J. Opt. Soc. Am. B, OSA, vol. 40, No. 10, pp. 2511-2518, Sept. 2023.

[] Y. Ogawa, S. Tadokoro, S. Suyama, M. Iwabuchi, T. Nishimura, T. Sato, J. Hagiwara, and T. Ohgane, “Smart radio environments with intelligent reflecting surfaces for 6G sub-terahertz-band communications,” Trans. Commun., IEICE, vol. E106-B, no. 9, pp.735-747, Sept. 2023.

[] T. Fujisawa, T. Mitarai, T. Okimoto, N. Kono, N. Fujiwara, T. Sato, H. Yagi, and K. Saitoh, “Bayesian design of mosaic-based mode multiplexers for various wavelength bands,” Optics Express, OSA, vol. 31, no. 16, pp. 26842-26853, July 2023.

[] T. Sato, T. Fujisawa, M. Wada, T. Mori, T. Sakamoto, R. Imada, T. Matsui, K. Nakajima, and K. Saitoh, “Design of silica-PLC LP11 mode rotator based on adiabatic mode conversion,” Optics Express, OSA, vol. 31, no. 15, pp. 23910-23922, July 2023.

[] Y. Sagae, T. Matsui, T. Mori, T. Sakamoto, T. Iwaya, T. Sato, K. Saitoh, and K. Nakajima, “Weakly coupled homogeneous 3-mode 4-core fiber with standard cladding diameter,” J. Lightw. Technol., IEEE, vol. 41, no. 12, pp. 3950-3956, June 2023.

[] 望月 大瑚, 西村 寿彦, 佐藤 孝憲, 小川 恭孝, 萩原 淳一郎, 大鐘 武雄, “サブテラヘルツ帯通信におけるマルチパスの遅延推定に基づくチャネル予測,” 電子情報通信学会論文誌B, Vol. J106-B, No. 6, pp. 361-372, June 2023.

[] Z. Zhao, Y. Wang, T. Sato, T. Fujisawa, and K. Saitoh, “Investigation of heterogeneous step-index 2LP-mode multi-core fibers based on two-ring layout with standard cladding diameter” Opt. Contin., OSA, vol. 2, no. 5, pp. 1137-1147, May 2023.

[] T. Sato, K. Homma, T. Fujisawa, Y. Sagae, T. Sakamoto, T. Matsui, and K. Nakajima, “Mode converter using bent and twisted coupled-multicore fibers for group delay spread reduction,” Opt. Fiber Technol., Elsevier, vol. 77, Art. 103286, pp. 1-18, May 2023.

[] H. Wang, T. Fujisawa, T. Sato, T. Mori, T. Sakamoto, Y. Yamashita, R. Imada, K. Nakajima, and K. Saitoh, “6-mode and 10-mode photonic lantern mode multi/demultiplexers based on silica planar lightwave circuit,” Opt. Commun., Elsevier, vol. 529, Art. 129098, pp. 1-9, Feb. 2023.

[] (invited) Y. Ogawa, T. Utsuno, T. Nishimura, T. Ohgane, and T. Sato, “Sub-terahertz MIMO spatial multiplexing in indoor propagation environments,” Trans. Commun., IEICE, vol. E105.B, no. 10, pp. 1130-1138, Oct. 2022.

[] T. Muratsubaki, T. Fujisawa, Y. Sawada, T. Sato, and K. Saitoh, “Proposal of mosaic-based 2 × 2 3-dB couplers for prospective on-chip communication in the mid-infrared wavelengths around 2.1 µm,” J. Opt. Soc. Am. B, OSA, vol. 39, No. 9, pp. 2522-2530, Aug. 2022.

[] A. Hirai, Y. Matsumoto, T. Sato, T. Kawai, A. Enokihara, S. Nakajima, A. Kanno, and N. Yamamoto, “Mach-Zehnder optical modulator integrated with tunable multimode interference coupler of Ti:LiNbO₃ waveguides for controlling modulation extinction ratio,” Trans. Electron., IEICE, vol. E105.C, no. 8, pp. 385-388, Aug. 2022.

[] T. Sato and A. Enokihara, “An electro-optic full adder designed with coupled Si ring resonators for highly dense integration,” Results in Optics, Elsevier, vol. 8, Art. 100230, pp. 1–7, Aug. 2022.

[] Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “Comparison of scalar and vector WFM method through the design of high-Δ waveguide lenses,” Photon. Technol. Lett., IEEE, vol. 34, no. 10, pp. 533–536, May 2022.

[] Y. Kase, T. Nishimura, T. Ohgane, Y. Ogawa, T. Sato, and Y. Kishiyama, “Accuracy improvement in DOA estimation with deep learning,” Trans. Commun., IEICE, vol. E105-B, No. 5, pp. 588–599, May. 2022.

[] Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “A novel algorithm of wavefront-matching method for stable and efficient design of Si waveguides,” Photon. Technol. Lett., IEEE, vol. 34, no. 7, pp. 359–362, Apr. 2022.

[] T. Muratsubaki, T. Fujisawa, Y. Sawada, T. Sato, and K. Saitoh, “Direct-binary-search algorithm for fabrication-tolerant photonic-crystal-like subwavelength structures and its application to a four-mode waveguide crossing in 2-µm waveband,” Jpn. J. Appl. Phys, vol. 61, No. 4, pp. 042003-1–042003-9, Apr. 2022.

[] Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “Broadband silicon four-mode multi/demultiplexer designed by wavefront matching method,” Optics Express, OSA, vol. 29, no. 17, pp. 27322–27331, Aug. 2021.

[] A. Hirai, Y. Matsumoto, T. Sato, T. Kawai, A. Enokihara, S. Nakajima, and N. Yamamoto “Optical multimode interference couplers of Ti:LiNbO3 waveguides and electrical tuning of power splitting ratio,” Opt. Commun., Elsesvier, vol. 501, p. 127325, Aug. 2021.

[] K. Nakamura, T. Fujisawa, T. Sato, and K. Saitoh, “High-tolerance CWDM4 wavelength multiplexer based on 2×2/2×1 MZ filters with polarization multiplexing,” IEICE Electronics Express, IEICE, vol. 18, no. 8, p. 20210110, Apr. 2021.

[] D. Furubayashi, Y. Kashiwagi, T. Sato, T. Kawai, A. Enokihara, N. Yamamoto, and T. Kawanishi, “Electro-optic modulator for compensation of third-order intermodulation distortion using frequency chirp modulation,” IEICE Transactions on Electronics, IEICE, vol. E103.C, no.11, pp. 653-660, Nov. 2020.

[] T. Sato and A. Enokihara, “Ultrasmall design of a universal linear circuit based on microring resonators,” Optics Express, OSA, vol. 27, no. 23, pp. 33005–33010, Nov. 2019.

[] K. Yoshida, T. Fujisawa, T. Sato, and K. Saitoh, “Optimum index profile of few-mode coupled multicore fibers for reducing the group delay spread,” Optics Express, OSA, vol. 27, no. 11, pp. 16281–16295, May 2019.

[] Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “CMOS-compatible Si-wire polarization beam splitter based on wavelength-insensitive coupler,” IEICE Electronics Express, IEICE, vol. 16, no. 8, p. 20181126, Feb. 2019.

[] T. Sato, T. Fujisawa, and K. Saitoh, “All-optical diode suppressing broadband backward transmission using single- and four-port photonic crystal cavities,” Photonics Journal, IEEE, vol. 11, no. 1, p. 4900214, Feb. 2019.

[] M. Akie, T. Fujisawa, T. Sato, M. Arai, and K. Saitoh, “GeSn/SiGeSn multiple-quantum-well electroabsorption modulator with taper coupler for mid-infrared Ge-on-Si platform,” J. Sel. Top. Quantum Electron., IEEE, vol. 24, no. 6, pp. 3400208-1–3400208-8, Nov. 2018.

[] S. Nakano, T. Fujisawa, T. Sato, and K. Saitoh, “Beam propagation analysis of optical activity and circular dichroism in helically twisted photonic crystal fiber,” Jpn. J. Appl. Phys., vol. 57, no. 8S2, pp. 08PF06-1–08PF06-5, July 2018.

[] Y. Sawada, T. Sato, T. Fujisawa, and K. Saitoh, “Development of the wavefront matching method based on the 3-D finite-element method and its application to Si-wire mode converters,” J. Lightw. Technol., IEEE, vol. 37, no. 17, pp. 3652–3659, Jun. 2018.

[] T. Sato, T. Fujisawa, and K. Saitoh, “Design of a high-forward-transmission all-optical diode based on cascaded side-coupled photonic crystal cavities,” J. Opt. Soc. Am. B, OSA, vol. 34, no. 12, pp. 2493–2500, Dec. 2017.

[] K. Saitoh, T. Fujisawa, and T. Sato, “Coiling size dependence of group delay spread in coupled multicore fibers without intentional twisting,” J. Lightw. Technol., IEEE, vol. 35, no. 20, pp. 4559–4566, Oct. 2017.

[] T. Fujisawa, T. Sato, and K. Saitoh, “Full-vector finite-element beam propagation method for helicoidal waveguides and its application to twisted photonic crystal fiber,” J. Lightw. Technol., IEEE, vol. 35, no. 14, pp. 2894–2901, July 2017. ; T. Fujisawa, T. Sato, and K. Saitoh, Errata to “Full-Vector finite-element beam propagation method for helicoidal waveguides and its application to twisted photonic crystal fiber,” J. Lightw. Technol., IEEE, vol. 36, no. 18, pp. 4211–4212, Aug. 2018.

[] T. Fujisawa, S. Makino, T. Sato, and K. Saitoh, “Low-loss, compact, and fabrication-tolerant Si-wire 90° waveguide bend using clothoid and normal curves for large scale photonic integrated circuits,” Optics Express, OSA, vol. 25, no. 8, pp. 9150–9159, Apr. 2017.

[] T. Sato, S. Makino, T. Fujisawa, and K. Saitoh, “Design of a reflection-suppressed all-optical diode based on asymmetric L-shaped nonlinear photonic crystal cavity,” J. Opt. Soc. Am. B, OSA, vol. 33, no. 1, pp. 54–61, Jan. 2016.

[] S. Makino, T. Sato, Y. Ishizaka, T. Fujisawa, and K. Saitoh, “Three-dimensional finite-element time-domain beam propagation method and its application to 1-D photonic crystal-coupled resonator optical waveguide,” J. Lightw. Technol., IEEE, vol. 33, no. 18, pp. 3836–3842, Aug. 2015.

[] T. Sato, S. Makino, Y. Ishizaka, T. Fujisawa, and K. Saitoh, “A rigorous definition of nonlinear parameter γ and effective area Aeff for photonic crystal optical waveguides,” J. Opt. Soc. Am. B, OSA, vol. 32, no. 6, pp. 1245–1251, Jun. 2015.

[] T. Sato, S. Makino, Y. Ishizaka, T. Fujisawa, and K. Saitoh, “Three-dimensional finite-element mode-solver for nonlinear periodic optical waveguides and its application to photonic crystal waveguides,” J. Lightw. Technol., IEEE, vol. 32, no. 21, pp. 4011–4019, Nov. 2014.

Conference proceedings (peer-reviewed)

[] Y. Hayashi, T. Nishimura, T. Sato, Y. Ogawa, and T. Ohgane, “Performance evaluation of loose beamforming using direct-binary search in massive MIMO system,” International Conference on Computing, Networking and Communications (ICNC 2024), Hawaii, USA, Feb. 19-22, 2024.

[] J. Hagiwara, K. Matsumura, H. Asumi, Y. Kasuga, T. Nishimura, T. Sato, Y. Ogawa, and T. Ohgane “Near-optimal stochastic MIMO signal detection with a mixture of t-distributions prior,” IEEE Global Communications Conference (IEEE GLOBECOM 2023), pp. 6633-6639, Kuala Lumpur, Malaysia, Dec. 4-8, 2023.

[] S. Tadokoro, T. Nishimura, T. Sato, Y. Ogawa, and T. Ohgane, “Considerations on IRS control based on beamforming for sub-terahertz-band communications,” The 2023 International Conference on Emerging Technologies for Communications (ICETC 2023), Sapporo, Japan, Nov. 29-Dec. 1, 2023.

[] N. Hamada, T. Nishimura, T. Sato, Y. Ogawa, and T. Ohgane, “Study on subarray beam allocation for sub-terahertz-band MIMO spatial multiplexing in indoor office environments,” The 2023 International Conference on Emerging Technologies for Communications (ICETC 2023), Sapporo, Japan, Nov. 29-Dec. 1, 2023.

[] T. Muratsubaki, T. Fujisawa, T. Sato, and K. Saitoh, “Proposal of dual-Mode adiabatic 3-dB coupler via shortcuts to adiabaticity at wavelength 2.1 µm,” IEEE Photonics Conference (IPC 2023), Paper. WB2.4, Orland, USA, Nov. 12-16, 2023.

[] T. Sato, T. Fujisawa, Y. Sawada, T. Mitarai, T. Hiratani, T. Okimoto, T. Ishikawa, N. Fujiwara, H. Yagi, and K. Saitoh, “Designs of resonant-characteristics-monitorable Si wavelength filters for heterogeneously integrated tunable lasers,” IEEE Photonics Conference (IPC 2023), Paper. TuB2.3, Orland, USA, Nov. 12-16, 2023.

[] G. Ocampo, T. Sato, Y. Amma, and K. Saitoh, “Polarization-mode dispersion of different core types in heterogeneous multi-core fibers,” IEEE Photonics Conference (IPC 2023), Paper. MB1.5, Orland, USA, Nov. 12-16, 2023.

[] Z. Zhao, T. Sato, T. Fujisawa, and K. Saitoh, “Design of heterogeneous 4LP-mode multicore fiber with two-ring layout,” Asia Communications and Photonics Conference (ACP), Paper. ACPPOEM-0726-16, Wuhan, China, Nov. 4-7, 2023.

[] D. A. Ando, T. Nishimura, T. Sato, T. Ohgane, Y. Ogawa, and J. Hagiwara, “Performance analysis of DNN-PCA for DOA estimation with three radio wave sources,” The International Symposium on Communications and Information Technologies (ISCIT), Sydney, Australia, Oct. 16-18, 2023.

[] S. Ochiai, T. Fujisawa, K. Nakamura, T. Sato, M. Okano, and K. Saitoh, "S+C+L band tapered asymmetric directional coupler for broadband polarization splitter-rotator,” Microoptics Conference (MOC), Paper H-4, Miyazaki, Japan, Sep. 24-27, 2023.

[] H. Wang, T. Fujisawa, T. Sato, and K. Saitoh, "Proposal of 5-mode multiplexer using pillar type photonic crystal waveguides,” Microoptics Conference (MOC), Paper PO-3, Miyazaki, Japan, Sep. 24-27, 2023.

[] K. Maeda, T. Sato, T. Fujisawa, T. Mitarai, T. Hiratani, T. Okimoto, T. Ishikawa, N. Kono, N. Fujiwara, H. Yagi, and K. Saitoh, "High tolerant design of Peltier-free Si wavelength filter using Mach-Zehnder interferometer for DWDM application,” Microoptics Conference (MOC), Paper PO-4, Miyazaki, Japan, Sep. 24-27, 2023.

[] R. Ima, T. Fujisawa, M. Wada, T. Mori, T. Sakamoto, R. Imada, T. Sato, T. Matsui, K. Nakajima, and K. Saitoh, "Wavelength insensitive three-mode directional coupler designed by wavefront matching method for broadband mode- dependent-loss equalizer,” Microoptics Conference (MOC), Paper PO-44, Miyazaki, Japan, Sep. 24-27, 2023.

[] T. Mitarai, T. Fujisawa, Y. Sawada, T. Okimoto, N. Kono, N. Fujiwara, T. Muratsubaki, T. Sato, K. Saitoh, and H. Yagi, “Compact passive waveguides using mosaic-based device with triangular lattice photonic crystal-like structure,” The 2023 International Conference on Solid State Devices and Materials (SSDM 2023), Paper H-7-02, Nagoya, Japan, Sep. 5-8, 2023.

[] H. Wang, T. Fujisawa, T. Sato, and K. Saitoh, “Proposal of an ultra-compact mode multiplexer using air-hole type photonic crystal waveguides,” The 28th OptoElectronics and Communications Conference (OECC), Paper OECC2023-0317-5, Shanghai, China, July 2-6, 2023.

[] Z. Zhao, T. Sato, T. Fujisawa, T. Iwaya, Y. Sagae, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “Design of double-cladding heterogeneous 2LP-Mode 6-Core fiber with two-ring layout,” The 28th OptoElectronics and Communications Conference (OECC), Paper OECC2023-0317-7, Shanghai, China, July 2-6, 2023.

[] (invited) T. Mori, T. Fujisawa, T. Sakamoto, T. Sato, K. Saitoh, and K. Nakajima, “Planar lightwave circuit device for spatial mode multiplexing transmission,” The 7th International Symposium on Extremely Advanced Transmission Technologies (EXAT), Paper F1.2, Matsue, Japan, May 17-19, 2023.

[] T. Muratsubaki, T. Fujisawa, T. Sato, and K. Saitoh, “Compact mode-evolution-based 2-mode 3-dB coupler in the 2-µm waveband using shortcuts to adiabaticity,” The 7th International Symposium on Extremely Advanced Transmission Technologies (EXAT), Paper P-04, Matsue, Japan, May 17-19, 2023.

[] H. Wang, T. Fujisawa, T. Sato, T. Mori, T. Sakamoto, Y. Yamashita, R. Imada, K. Nakajima, and K. Saitoh, “Optimization of PLC 10-mode photonic lantern mode multiplexer,” The 7th International Symposium on Extremely Advanced Transmission Technologies (EXAT), Paper P-06, Matsue, Japan, May 17-19, 2023.

[] G. Ocampo, T. Sato, T. Fujisawa, M. Nakagawa, and K. Saitoh, “Relationship between polarization mode dispersion and crosstalk in heterogeneous multi-core fibers with different cladding diameters,” Optical Fiber Communication Conference (OFC), Paper M3B.4, San Diego, USA, Mar. 5-9, 2023.

[] T. Iwaya, Y. Sagae, T. Mori, T. Sakamoto, T. Matsui, T. Sato, K. Saitoh, and K. Nakajima, “Design of three-mode dual-step index pure silica core fiber with low differential mode delay and low loss characteristics,” Photonics West, Paper 12429-16, San Francisco, USA, Jan. 28-Feb. 2, 2023.

[] D. A. Ando, T. Nishimura, T. Sato, T. Ohgane, Y. Ogawa, and J. Hagiwara, “A proposal of an end-to-end DoA estimation system aided by deep learning,” 25th International Symposium on Wireless Personal Multimedia Communications (WPMC2022), Herning, Denmark, Oct. 30-Nov. 2, 2022.

[] Y. Sagae, T. Matsui, T. Sakamoto, T. Iwaya, T. Mori, T. Sato, K. Saitoh, and K. Nakajima, “A 125-μm cladding diameter uncoupled 3-mode 4-core fibre with the highest core multiplicity factor,” European Conference on Optical Communication (ECOC), Paper Tu3A.2, Basel, Switzerland, Sept. 18-22, 2022.

[] T. Mori, T. Fujisawa, J. Sakamoto, Y. Yamashita, T. Sakamoto, R. Imada, R. Ima, T. Sato, K. Watanabe, R. Kasahara, T. Hashimoto, K. Saitoh, and K. Nakajima, “Variable mode-dependent-loss equalizer based on silica-PLC for two-LP-mode transmission,” European Conference on Optical Communication (ECOC), Paper Tu5.11, Basel, Switzerland, Sept. 18-22, 2022.

[] M. Miyoshi, T. Nishimura, T. Sato, T. Ohgane, Y. Ogawa and J. Hagiwara, “Parameter-learned AMP for MIMO signal detection,” IEEE VTS Asia Pacific Wireless Communications Symposium (IEEE VTS APWCS), Paper Th-5G1, Aug. 24-26, 2022.

[] Y. Asama, T. Fujisawa, T. Sato, T. Mori, T. Sakamoto, R. Imada, Y. Yamashita, K. Nakajima, and K. Saitoh, “Cascaded wavefront-matching-method designed 6-mode-exchangers for MDL management in MDM transmission,” Pacific Rim Conference on Lasers and Electro-Optics (CLEO-PR), Paper CWP10B-05, Sapporo, Japan, July 31-Aug. 5, 2022.

[] G. Ocampo, T. Sato, T. Fujisawa, Y. Amma, and K. Saitoh, “Analysis of crosstalk dependence on cladding diameter in heterogeneous multi-core fibers by considering polarization-mode coupling effects,” 27th Optoelectronics and Communications Conference / International Conference on Photonics in Switching and Computing 2022 (OECC/PSC 2022), Paper. TuC2-4, Toyama, Japan, July 3-6, 2022.

[] T. Mitarai, T. Fujisawa, T. Okimoto, N. Kono, N. Fujiwara, Y. Sawada, T. Muratsubaki, T. Sato, K. Saitoh, H. Yagi, “Compact power splitters with mosaic-based structure designed by bayesian direct-binary-search method,” 27th Optoelectronics and Communications Conference / International Conference on Photonics in Switching and Computing 2022 (OECC/PSC 2022), Paper. TuE2-4, Toyama, Japan, July 3-6, 2022.

[] T. Fujisawa, T. Mori, J. Sakamoto, Y. Yamashita, T. Sakamoto, R. Imada, R. Ima, T. Sato, K. Watanabe, R. Kasahara, T. Hashimoto, K. Nakajima, K. Saitoh, “Silica-PLC based mode-dependent-loss equalizer for two LP mode transmission,” Optical Fiber Communication Conference (OFC), Paper M4J.4, San Diego, USA, Mar. 6-10, 2022.

[] K. Matsumura, J. Hagiwara, T. Nishimura, T. Ohgane, Y. Ogawa, and T. Sato, “A novel MIMO signal detection method using Hamiltonian Monte Carlo approach,” The 24th International Symposium On Wireless Personal Multimedia Communications (WPMC 2021), Paper 1570749345, Okayama, Japan, Dec. 14-16, 2021.

[] T. Sato, T. Fujisawa, T. Mitarai, T. Hiratani, T. Okimoto, T. Ishikawa, N. Kono, N. Fujiwara, H. Yagi, and K. Saitoh, “Design of resonant-characteristics-monitorable Si wavelength filter using face-to-face loop mirrors for heterogeneous integrated tunable lasers,” IEEE International Conference on Group IV Photonics (GFP2021), Paper ThB2.3, Virtual Conference, Dec. 7-10, 2021.

[] (invited) T. Sato, “Optical MIMO signal processing based on planar lightwave circuit,” 4th International Workshop on Photonics applied to Electromagnetic Measurements in Sapporo (PEM2021), Virtual Conference, Nov. 29-30, 2021.

[] Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “Switchable mode converter for four-mode MDM system assisted by passive mode controlling device designed by wavefront matching method,” The 26th Microoptics Conference (MOC 2021), Paper PO-13, Virtual Conference, Sept. 26-29, 2021.

[] T. Muratsubaki, T. Fujisawa, Y. Sawada, T. Sato, and K. Saitoh, “Fabrication-Tolerant Four-Mode Waveguide Crossing Based on PhC-like Subwavelength Structures at 2 μm,” Advanced Photonics Congress (APC), Paper IM2A.3, Virtual Conference, July 26-30, 2021.

[] Y. Sawada, T, Fujisawa, T. Sato, and K. Saitoh, “Experimental demonstration of broadband silicon 4-mode (de)multiplexer designed by wavefront-matching method,” Optical Fiber Communication Conference (OFC), Paper F2B.4, San Francisco, USA, June 2021.

[] K. Nakamura, T. Fujisawa, Y. Sawada, T. Sato, and K. Saitoh, “Ultrasmall O-band CWDM 4λ MUX based on Mosaic Structure for Dense Optical Interconnects,” Conference on Lasers and Electro-Optics (CLEO), Paper JW1A.105, (Virtual Conference), May 2021.

[] D. A. Ando, T. Nishimura, T. Ohgane, Y. Ogawa, J. Hagiwara, and T. Sato, “A preliminary study on behavior of GaBP messages in massive MIMO signal detection,” The 2020 International Conference on Emerging Technologies for Communications (ICETC 2020), Paper K1-2, (Virtual Conference), Dec. 2-4, 2020.

[] Y. Kase, T. Nishimura, T. Ohgane, Y. Ogawa, T. Sato, D. Kitayama, and Y. Kishiyama, “A consideration on accuracy improvement in DOA estimation of two targets with deep learning,” The 2020 International Conference on Emerging Technologies for Communications (ICETC 2020), Paper P1-3, (Virtual Conference), Dec. 2-4, 2020.

[] A. Hirai, T. Sato, T. Kawai, A. Enokihara, S. Nakajima, and N. Yamamoto, “Design and fabrication of MMI optical coupler using Ti-diffused lithium niobate waveguides,” The 2020 International Topical Meeting on Microwave Photonics (MWP 2020), P.13, (Virtual Conference), Nov. 24-26, 2020.

[] (invited) K. Saitoh, T. Fujisawa, and T. Sato, “Control of Group Delay Spread in Randomly-Coupled Multicore Fibers,” Optoelectronics and Communications Conference (OECC 2020), Paper T3-1, Taipei, Taiwan, Oct 4-8, 2020.

[] K. Nakamura, T. Sato, T. Fujisawa, and K. Saitoh, “Nonreciprocity enhancement of graphene-on-Si waveguide using one-dimensional photonic crystal,” The 24th Microoptics Conference (MOC 2019), Paper P-48, Toyama, Japan, Nov. 17-20, 2019.

[] T. Sato, T. Fujisawa, and K. Saitoh, “Ultra-robust design of mode (de)multiplexer based on asymmetrical directional coupler using wire and one-side rib waveguides,” 24th Optoelectronics and Communications Conference / International Conference on Photonics in Switching and Computing 2019 (OECC/PSC 2019), Paper. TuE2-3, Fukuoka, Japan, July 7-11, 2019.

[] K. Nishimura, T. Sato, T. Fujisawa, Y. Amma, K. Takenaga, K. Aikawa, and K. Saitoh, “Cladding diameter dependence of inter-core crosstalk in heterogeneous multicore fibers,” 24th Optoelectronics and Communications Conference / International Conference on Photonics in Switching and Computing 2019 (OECC/PSC 2019), Paper. ThG3-2, Fukuoka, Japan, July 7-11, 2019.

[] Y. Yasui, K. Yoshida, T. Sato, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Simple GDS estimation method for coupled multicore fibers with various core layouts,” International Symposium on Extremely Advanced Transmission Technologies (EXAT 2019), Paper P-19, Ise, Japan, May 29-31, 2019.

[] Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “First experimental demonstration of wavefront-matching-method-designed silicon mode converters,” Optical Fiber Communication Conference (OFC 2019), Paper W3B.4, San Diego, USA, Mar. 3-7, 2019.

[] J. Takano, T. Fujisawa, T. Sato, Y. Sawada, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Low-loss and fabrication-tolerant Si four-wavelength multiplexer using higher-order mode for 100/400GbE,” Optical Fiber Communication Conference (OFC), Paper Tu2J.2, San Diego, USA, Mar. 3-7, 2019.

[] T. Sato, K. Yoshida, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Suppression of group-delay spread in coupled two-LP-mode four-core fiber,” IEEE Photonics Conference (IPC 2018), Paper MA4.2, Reston, USA, Sept. 30-Oct. 4, 2018. [

[] T. Sato, T. Fujisawa, and K. Saitoh, “Novel all-optical diode based on single-port and four-port photonic crystal cavities,” OptoElectronics and Communications Conference (OECC 2018), Paper 4D2-2, Jeju, Korea, July 2-6, 2018.

[] J. Takano, T. Sato, Y. Sawada, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Proposal of Si four-wavelength multiplexer using higher-order mode for 100GbE,” OptoElectronics and Communications Conference (OECC 2018), Paper 4E2-4, Jeju, Korea, July 2-6, 2018.

[] Y. Sawada, T. Sato, T. Fujisawa, and K. Saitoh, “A broadband silicon two-mode multiplexer designed by wavefront matching method,” OptoElectronics and Communications Conference (OECC 2018), Paper 5E4-4, Jeju, Korea, July 2-6, 2018.

[] S. Nakano, T. Fujisawa, T. Sato, and K. Saitoh, “Beam propagation analysis of optical activity and circular dichroism in helically twisted photonic crystal fiber,” The 22nd Microoptics Conference (MOC 2017), Paper P-16, Tokyo, Japan, Nov. 19-22, 2017.

[] K. Yoshida, T. Fujisawa, T. Sato, and K. Saitoh, “Group delay spread analysis of few-mode, coupled 3-core fibres: Optimum index profile and maximum transmission distance for strong coupling regime,” European Conference on Optical Communications (ECOC 2017), Paper P1.SC1.8, Gothenburg, Sweden, Sept. 17-21, 2017.

[] T. Sato, T. Fujisawa, and K. Saitoh, “High-forward-transmission all-optical diode based on cascaded L3 photonic crystal cavities,” The 24th Congress of International Commission for Optics (ICO-24), Paper Th3E-03, Tokyo, Japan, Aug. 21-25, 2017.

[] M. Akie, T. Sato, M. Arai, T. Fujisawa, and K. Saitoh, “A compact and low-loss GeSn electroabsorption modulator using vertical multimode interference for mid-infrared Ge-on-Si platform,” 2017 Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR 2017), Singapore, Jul. 31-Aug. 4, 2017.

[] (invited) K. Saitoh, T. Fujisawa, and T. Sato, “Design and analysis of weakly- and strongly-coupled multicore fibers,” Photonic Networks and Devices in Proceedings Advanced Photonics 2017 (IPR, NOMA, Sensors, Networks, SPPCom, PS), Paper NeTu2B.5, New Orleans, USA, Jul. 24-27, 2017.

[] T. Sato, M. Akie, M. Arai, T. Fujisawa, and K. Saitoh, “Highly efficient GeSn electroabsorprtion modulator using higher-order-mode for mid-infrared Ge-on-Si platform,” Conference on Lasers and Electro-Optics (CLEO 2017), Paper JW2A.110, San Jose, USA, May 14-19, 2017.

[] S. Makino, M. Suga, T. Sato, T. Fujisawa, and K. Saitoh, “Ultimately low-loss and compact Si wire 90° waveguide bend composed of clothoid and normal curves for dense optical interconnect PICs,” Optical Fiber Communication Conference (OFC 2017), Paper Th3E.2, Los Angeles, USA, Mar. 19-23, 2017.

[] T. Sato, S. Makino, T. Fujisawa, and K. Saitoh, “A simple design method of reflection-suppressed photonic crystal cavity with asymmetric waveguides,” IEEE Photonics Conference (IPC 2016), pp. 91–92, Hawaii, USA, Oct. 2-6, 2016.

[] T. Sato, S. Makino, Y. Ishizaka, and K. Saitoh, “Investigation of nonlinear characteristics in a 1-D slotted photonic crystal coupled resonator optical waveguide with modulated mode-gap,” in Optical Fibre Technology, 2014 OptoElectronics and Communication Conference and Australian Conference on (OECC/ACOFT 2014), pp. 673–675, Melbourne, Australia, Jul. 6-10, 2014.