T. Ishihara and S. Sugiura, "Differential Multi-Carrier Faster-Than-Nyquist Signaling in Doubly Selective Fading Channel," IEEE Transactions on Vehicular Technology, vol. 73, no. 1, pp. 1424-1429, Jan. 2024. IEEE Xplore
P. Chaki, T. Ishihara, and S. Sugiura, "Precoded Filterbank Multicarrier Index Modulation With Non-Orthogonal Subcarrier Spacing," IEEE Transactions on Communications, vol. 71, no. 2, pp. 700-713, Feb. 2023. IEEE Xplore
J. Zhou, T. Ishihara, and S. Sugiura, "Precoded Faster-Than-Nyquist Signaling for Doubly Selective Underwater Acoustic Communication Channel," IEEE Wireless Communications Letters, vol. 11, no. 10, pp. 2041-2045, Oct. 2022. IEEE Xplore
P. Chaki, T. Ishihara,and S. Sugiura, "Eigendecomposition-Precoded Faster-Than-Nyquist Signaling With Index Modulation," IEEE Transactions on Communications, vol. 70, no. 7, pp. 4822-4836, July 2022. IEEE Xplore
T. Ishihara and S. Sugiura, "Reduced-complexity FFT-spread multi-carrier faster-than-Nyquist signaling in frequency-selective fading channel," IEEE Open Journal of the Communications Society, vol. 3, pp. 530-542, 2022. IEEE Xplore
T. Ishihara and S. Sugiura, "Eigendecomposition-precoded faster-than-Nyquist signaling with optimal power allocation in frequency-selective fading channel," IEEE Transactions on Wireless Communications, vol. 21, no. 3, pp. 1681-1693, Mar. 2022. IEEE Xplore
T. Ishihara, S. Sugiura, and L. Hanzo "The evolution of faster-than-Nyquist signaling," IEEE Access, vol. 9, pp. 86535-86564, June 2021. IEEE Xplore
K. Masaki, T. Ishihara, and S. Sugiura, "Tradeoff Between Calculation Precision and Information Rate in Eigendecomposition-Based Faster-than-Nyquist Signaling," IEEE Access, vol. 8, pp. 223461-223471, Dec. 2020. IEEE Xplore
S. Osaki, T. Ishihara, and S. Sugiura, "Eigenvalue-decomposition-precoded ultra-dense non-orthogonal frequency-division multiplexing," IEEE Transactions on Wireless Communications, vol. 19, no. 12, pp. 8165-8178, Dec. 2020. IEEE Xplore
Y. Akiba, T. Ishihara, and S. Sugiura, "Variable-block-length joint channel estimation and data detection for spatial modulation over time-varying channels," IEEE Transactions on Vehicular Technology, vol. 69, no. 11, pp. 13964-13969, Nov. 2020. IEEE Xplore
T. Ishihara and S. Sugiura, "SVD-precoded faster-than-Nyquist signaling with optimal and truncated power allocation," IEEE Transactions on Wireless Communications, vol. 18, no. 12, pp. 5909-5923, Dec. 2019. IEEE Xplore (Corrections)
S. Osaki, M. Nakao, T. Ishihara, and S. Sugiura, "Differentially modulated spectrally efficient frequency-division multiplexing," IEEE Signal Processing Letters, vol. 26, no. 7, pp. 1046-1050, July 2019. IEEE Xplore
C. Sagayama, T. Ishihara, and S. Sugiura, "Performance analysis and constellation optimization of star-QAM-aided differential faster-than-Nyquist signaling," IEEE Signal Processing Letters, vol. 26, no. 1, pp. 144-148, Jan. 2019. IEEE Xplore
T. Ishihara and S. Sugiura, "Differential faster-than-Nyquist signaling," IEEE Access, vol. 6, pp. 4199-4206, Jan. 2018. IEEE Xplore
M. Nakao, T. Ishihara, and S. Sugiura, "Dual-mode time-domain index modulation for Nyquist-criterion and faster-than-Nyquist single-carrier transmissions," IEEE Access, vol. 5, pp. 27659-27667, Nov. 2017. IEEE Xplore
S. Sugiura, T. Ishihara, and M. Nakao, "State-of-the-art design of index modulation in the space, time, and frequency domains: benefits and fundamental limitations," IEEE Access, vol. 5, pp. 21774-21790, Oct. 2017. IEEE Xplore
T. Ishihara and S. Sugiura, "Faster-than-Nyquist signaling with index modulation," IEEE Wireless Communications Letters, vol. 6, no. 5, pp. 630-633, Oct. 2017. (presented in WCL presentation session at IEEE International Conference on Communications 2018, Kansas City, USA.) IEEE Xplore
T. Ishihara and S. Sugiura, "Iterative frequency-domain joint channel estimation and data detection of faster-than-Nyquist signaling," IEEE Transactions on Wireless Communications, vol. 16, no. 9, pp. 6221-6231, Sep. 2017. IEEE Xplore (Telecom System Technology Award Incentive Award) (Yasujiro Niwa Outstanding Paper Award)
M. Nakao, T. Ishihara, and S. Sugiura, "Single-carrier frequency-domain equalization with index modulation," IEEE Communications Letters, vol. 21, no. 2, pp. 298-301, Feb. 2017. IEEE Xplore
T.Ishihara, H. Fukumoto, and Y. Fujino, "Closed-Form near-Optimal Signal Detection for Underwater Acoustic Communication Using Student's t-Distribution Approximation," in IEEE Global Communications Conference (GLOBECOM), Taipei, Taiwan, 8-12 Dec. 2025, in press.
P. Chaki, T. Ishihara, and S. Sugiura, "Precoded Non-Orthogonal Frequency Division Multiplexing with Subcarrier Index Modulation," in IEEE 95th Vehicular Technology Conference (VTC2022-Spring), Helsinki, Finland, 2022.
T. Ishihara and S. Sugiura, "FFT-spread faster-than-Nyquist signaling in frequency-selective fading channel," in IEEE International Conference on Communications (ICC), Virtual Conference, 16-20 May 2022.
P. Chaki, T. Ishihara, and S. Sugiura, "Eigenvalue decomposition precoded faster-than-Nyquist transmission of index modulated symbols," in IEEE International Symposium on Information Theory (ISIT), Virtual Conference, 12-20 July 2021.
T. Ishihara and S. Sugiura, "Precoded faster-than-Nyquist signaling with optimal power allocation in frequency-selective channel," in IEEE International Conference on Communications (ICC) Workshop, Virtual Conference, 14-23 June 2021.
S. Osaki, T. Ishihara, and S. Sugiura, "Non-orthogonal frequency-division multiplexing based on eigenvalue decomposition," in IEEE 92th Vehicular Technology Conference, Victoria, B.C., Canada, 4-7 Oct. 2020.
K. Masaki, T. Ishihara, and S. Sugiura, "Effects of eigenvalue distribution on precoded faster-than-Nyquist signaling with power allocation," in IEEE 92th Vehicular Technology Conference, Victoria, B.C., Canada, 4-7 Oct. 2020.
T. Ishihara and S. Sugiura, "Optimal and suboptimal power allocation for SVD-precoded faster-than-Nyquist signaling," in IEEE 90th Vehicular Technology Conference, Honolulu, Hawaii, USA, 22-25 Sep. 2019. (IEEE VTS Tokyo Chapter 2019 Young Researcher's Encouragement Award)
T. Ishihara and S. Sugiura, "Faster-than-Nyquist signaling with differential encoding and non coherent detection," in IEEE International Conference on Acoustics, Speech and Signal Processing, Calgary, Alberta, Canada, 15-20 Apr. 2018.
T. Ishihara and S. Sugiura, "Frequency-domain equalization aided iterative detection of faster-than-Nyquist signaling with noise whitening," in IEEE International Conference on Communications, Kuala Lumpur, Malaysia, 23-27 May 2016.