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Ph.D. Thesis

Space-, time-, and frequency-domain permutation modulation designed for microwave and optical wireless communications

Authors: Naoki Ishikawa
Published in: Tokyo University of Agriculture and Technology Ph.D. Thesis, February 2017.

First-Authored IEEE Journal (Refereed)

2. Differential space-time coding dispensing with channel-estimation approaches the performance of its coherent counterpart in the open-loop massive MIMO-OFDM downlink

Authors: Naoki Ishikawa, Rakshith Rajashekar, Chao Xu, Shinya Sugiura, and Lajos Hanzo
Published in: IEEE Transactions on Communications, vol. 66, no. 12, pp. 6190—6204, December 2018.

3. 50 years of permutation, spatial and index modulation: From classic RF to visible light communications and data storage

Authors: Naoki Ishikawa, Shinya Sugiura, and Lajos Hanzo
Published in: IEEE Communications Surveys and Tutorials, vol. 20, no. 3, pp. 1905—1938, March 2018.

4. Rectangular differential spatial modulation for open-loop noncoherent massive-MIMO downlink

Authors: Naoki Ishikawa and Shinya Sugiura
Published in: IEEE Transactions on Wireless Communications, vol. 16, no. 3, pp. 1908—1920, March 2017.

5. Generalized spatial modulation based reduced-RF-chain millimeter-wave communications

Authors: Naoki Ishikawa, Rakshith Rajashekar, Shinya Sugiura, and Lajos Hanzo
Published in: IEEE Transactions on Vehicular Technology, vol. 66, no. 1, pp. 879—883, January 2017.

6. Subcarrier-index modulation aided OFDM — will it work?

Authors: Naoki Ishikawa, Shinya Sugiura, and Lajos Hanzo
Published in: IEEE Access, vol. 4, pp. 2580—2593, May 2016.

7. Maximizing constrained capacity of power-imbalanced optical wireless MIMO communications using spatial modulation

Authors: Naoki Ishikawa and Shinya Sugiura
Published in: Journal of Lightwave Technology, vol. 33, no. 2, pp. 519—527, January 2015.

8. Unified differential spatial modulation

Authors: Naoki Ishikawa and Shinya Sugiura
Published in: IEEE Wireless Communications Letters, vol. 3, no. 4, pp. 337—340, August 2014.

Co-Authored IEEE Journal (Refereed)

9. Finite-cardinality single-RF differential space-time modulation for improving the diversity-throughput tradeoff

Authors: Chao Xu, Peichang Zhang, Rakshith Rajashekar, Naoki Ishikawa, Shinya Sugiura, Li Wang, and Lajos Hanzo
Published in: IEEE Transactions on Communications, vol. 67, no. 1, pp. 318—335, January 2019.

10. Single-RF index shift keying aided differential space-time block coding

Authors: Chao Xu, Rakshith Rajashekar, Naoki Ishikawa, Shinya Sugiura, and Lajos Hanzo
Published in: IEEE Transactions on Signal Processing, vol. 66, no. 3, pp. 773—788, February 2018.

11. Algebraic differential spatial modulation is capable of approaching the performance of its coherent counterpart

Authors: Rakshith Rajashekar, Chao Xu, Naoki Ishikawa, Shinya Sugiura, K. V. S. Hari, and Lajos Hanzo
Published in: IEEE Transactions on Communications, vol. 65, no. 10, pp. 4260—4273, October 2017.

12. Full-diversity dispersion matrices from algebraic field extensions for differential spatial modulation

Authors: Rakshith Rajashekar, Naoki Ishikawa, Shinya Sugiura, K. V. S. Hari, and Lajos Hanzo
Published in: IEEE Transactions on Vehicular Technology, vol. 66, no. 1, pp. 385—394, January 2017.

IEEE Conference (Oral / Refereed)

1. Exit-chart-based design of irregular-precoded power-imbalanced optical spatial modulation

Authors: Naoki Ishikawa and Shinya Sugiura
Presented in: IEEE 82nd Vehicular Technology Conference (VTC Fall), Boston, USA, September 2015.
Acceptance rate: not yet public

2. Single- and multiple-RF aided non-coherent generalized spatial modulation

Authors: Naoki Ishikawa and Shinya Sugiura
Presented in: IEEE 79th Vehicular Technology Conference (VTC Spring), Seoul, Korea, May 2014.
Acceptance rate: 62%