Summary of Publications

Quantum Speedups for Wireless Communications

Post-Quantum Physical Layer Security

High-Mobility Wireless Communications

Index Modulation

Other Topics

Preprints

Journal

  1. Kein Yukiyoshi and Naoki Ishikawa, “Quantum search algorithm for binary constant weight codes,” Quantum Information Processing, vol. 23, pp. 360, October 2024. (arXiv)
  2. Kein Yukiyoshi, Taku Mikuriya, Hyeon Seok Rou, Giuseppe Thadeu Freitas de Abreu, and Naoki Ishikawa, “Quantum speedup of the dispersion and codebook design problems,” IEEE Transactions on Quantum Engineering, vol. 5, pp. 1–16, August 2024. (arXiv)
  3. Naoki Endo, Hiroki Iimori, Chandan Pradhan, Szabolcs Malomsoky, and Naoki Ishikawa, “Boosting spectral efficiency with data-carrying reference signals on the Grassmann manifold,” IEEE Transactions on Wireless Communications, vol. 23, no. 8, pp. 10137–10149, August 2024. (arXiv)
  4. Masaya Norimoto, Taku Mikuriya, and Naoki Ishikawa, “Quantum speedup for multiuser detection with optimized parameters in Grover adaptive search,” IEEE Access, vol. 12, pp. 83810–83821, June 2024.
  5. Yuki Sano, Kosuke Mitarai, Naoki Yamamoto, and Naoki Ishikawa, “Accelerating Grover adaptive search: Qubit and gate count reduction strategies with higher-order formulations,” IEEE Transactions on Quantum Engineering, vol. 5, April 2024. (arXiv)
  6. Kein Yukiyoshi and Naoki Ishikawa, “On the capacity of generalized quadrature spatial modulation,” IEEE Wireless Communications Letters, vol. 12, no. 12, pp. 2158–2162, December 2023. (arXiv)
  7. Yuki Sano, Masaya Norimoto, and Naoki Ishikawa, “Qubit reduction and quantum speedup for wireless channel assignment problem,” IEEE Transactions on Quantum Engineering, vol. 4, July 2023. (arXiv)
  8. Yuma Katsuki, Giuseppe Thadeu Freitas de Abreu, Koji Ishibashi, and Naoki Ishikawa, “Noncoherent massive MIMO with embedded one-way function physical layer security,” IEEE Transactions on Information Forensics and Security, vol. 18, pp. 3158–3170, May 2023. (arXiv)
  9. Yu Mizuno, Yasuhiro Ohishi, and Naoki Ishikawa, “A simple metric that correlates with public Wi-Fi throughput,” Electronics Letters, vol. 59, no. 8, pp. 1926–1939, April 2023.
  10. Masaya Norimoto, Ryuhei Mori, and Naoki Ishikawa, “Quantum algorithm for higher-order unconstrained binary optimization and MIMO maximum likelihood detection,” IEEE Transactions on Communications, vol. 71, no. 4, pp. 1926–1939, April 2023. (arXiv)
  11. Yuma Katsuki, Giuseppe Thadeu Freitas de Abreu, Koji Ishibashi, and Naoki Ishikawa, “A new noncoherent Gaussian signaling scheme for low probability of detection communications,” IEEE Wireless Communications Letters, vol. 12, no. 3, pp. 545–549, March 2023. (arXiv)
  12. Xiaodan Zhai, Guochao Song, Lixia Xiao, Guanghua Liu, Naoki Ishikawa, and Tao Jiang, “Error probability analysis for time-varying chaos unitary matrix based differential MIMO system,” IEEE Wireless Communications Letters, vol. 11, no. 7, pp. 1399–1403, July 2022.
  13. Naoki Ishikawa, Jehad M. Hamamreh, Eiji Okamoto, Chao Xu, and Lixia Xiao, “Artificially time-varying differential MIMO for achieving practical physical layer security,” IEEE Open Journal of the Communications Society, vol. 2, pp. 2180–2194, September 2021.
  14. Naoki Ishikawa, “Quantum speedup for index modulation,” IEEE Access, vol. 9, pp. 111114–111124, August 2021.
  15. Chao Xu, Yifeng Xiong, Naoki Ishikawa, Rakshith Rajashekar, Shinya Sugiura, Zhaocheng Wang, Soon Ng, Lie-Liang Yang, and Lajos Hanzo, “Space-, time- and frequency-domain index modulation for next-generation wireless: A unified single-/multi-carrier and single-/multi-RF MIMO framework,” IEEE Transactions on Wireless Communications, vol. 20, no. 6, pp. 3847–3864, February 2021.
  16. Lixia Xiao, Pei Xiao, Hang Ruan, Naoki Ishikawa, Lei Lu, Yue Xiao, and Lajos Hanzo, “Differentially-encoded rectangular spatial modulation approaches the performance of its coherent counterpart,” IEEE Transactions on Communications, vol. 68, no. 12, pp. 7593–7607, December 2020.
  17. Chao Xu, Naoki Ishikawa, Rakshith Rajashekar, Shinya Sugiura, Robert G. Maunder, Zhaocheng Wang, Lie-Liang Yang, and Lajos Hanzo, “Sixty years of coherent versus non-coherent tradeoffs and the road from 5G to wireless futures,” IEEE Access, vol. 7, pp. 178246–178299, December 2019.
  18. Rakshith Rajashekar, Chao Xu, Naoki Ishikawa, Lie-Liang Yang, and Lajos Hanzo, “Subcarrier subset selection-aided transmit precoding achieves full-diversity in index modulation,” IEEE Transactions on Vehicular Technology, vol. 68, no. 11, pp. 11031–11041, November 2019.
  19. Naoki Ishikawa, Rakshith Rajashekar, Chao Xu, Mohammed El-Hajjar, Shinya Sugiura, Lie-Liang Yang, and Lajos Hanzo, “Differential-detection aided large-scale generalized spatial modulation is capable of operating in high-mobility millimeter-wave channels,” IEEE Journal of Selected Topics in Signal Processing, vol. 13, no. 6, pp. 1360–1374, October 2019.
  20. Chao Xu, Peichang Zhang, Rakshith Rajashekar, Naoki Ishikawa, Shinya Sugiura, Zhaocheng Wang, and Lajos Hanzo, “``Near-perfect'' finite-cardinality generalized space-time shift keying,” IEEE Journal on Selected Areas in Communications, vol. 37, no. 9, pp. 2146–2164, September 2019.
  21. Rakshith Rajashekar, Chao Xu, Naoki Ishikawa, Lie-Liang Yang, and Lajos Hanzo, “Multicarrier division duplex aided millimeter wave communications,” IEEE Access, vol. 7, pp. 100719–100732, July 2019.
  22. Naoki Ishikawa, “IMToolkit: An open-source index modulation toolkit for reproducible research based on massively parallel algorithms,” IEEE Access, vol. 7, pp. 93830–93846, July 2019.
  23. Naoki Ishikawa, Yasuhiro Ohishi, and Kaori Maeda, “Nulls in the air: Passive and low-complexity QoS estimation method for a large-scale Wi-Fi network based on null function data frames,” IEEE Access, vol. 7, pp. 28581–28591, February 2019.
  24. Chao Xu, Peichang Zhang, Rakshith Rajashekar, Naoki Ishikawa, Shinya Sugiura, Li Wang, and Lajos Hanzo, “Finite-cardinality single-RF differential space-time modulation for improving the diversity-throughput tradeoff,” IEEE Transactions on Communications, vol. 67, no. 1, pp. 318–335, January 2019.
  25. Naoki Ishikawa, Rakshith Rajashekar, Chao Xu, Shinya Sugiura, and Lajos Hanzo, “Differential space-time coding dispensing with channel-estimation approaches the performance of its coherent counterpart in the open-loop massive MIMO-OFDM downlink,” IEEE Transactions on Communications, vol. 66, no. 12, pp. 6190–6204, December 2018.
  26. Naoki Ishikawa, Shinya Sugiura, and Lajos Hanzo, “50 years of permutation, spatial and index modulation: From classic RF to visible light communications and data storage,” IEEE Communications Surveys and Tutorials, vol. 20, no. 3, pp. 1905–1938, March 2018.
  27. Chao Xu, Rakshith Rajashekar, Naoki Ishikawa, Shinya Sugiura, and Lajos Hanzo, “Single-RF index shift keying aided differential space-time block coding,” IEEE Transactions on Signal Processing, vol. 66, no. 3, pp. 773–788, February 2018.
  28. Rakshith Rajashekar, Chao Xu, Naoki Ishikawa, Shinya Sugiura, K. V. S. Hari, and Lajos Hanzo, “Algebraic differential spatial modulation is capable of approaching the performance of its coherent counterpart,” IEEE Transactions on Communications, vol. 65, no. 10, pp. 4260–4273, October 2017.
  29. Naoki Ishikawa and Shinya Sugiura, “Rectangular differential spatial modulation for open-loop noncoherent massive-MIMO downlink,” IEEE Transactions on Wireless Communications, vol. 16, no. 3, pp. 1908–1920, March 2017.
  30. Rakshith Rajashekar, Naoki Ishikawa, Shinya Sugiura, K. V. S. Hari, and Lajos Hanzo, “Full-diversity dispersion matrices from algebraic field extensions for differential spatial modulation,” IEEE Transactions on Vehicular Technology, vol. 66, no. 1, pp. 385–394, January 2017.
  31. Naoki Ishikawa, Rakshith Rajashekar, Shinya Sugiura, and Lajos Hanzo, “Generalized spatial modulation based reduced-RF-chain millimeter-wave communications,” IEEE Transactions on Vehicular Technology, vol. 66, no. 1, pp. 879–883, January 2017.
  32. Naoki Ishikawa, Shinya Sugiura, and Lajos Hanzo, “Subcarrier-index modulation aided OFDM – will it work?,” IEEE Access, vol. 4, pp. 2580–2593, May 2016.
  33. Naoki Ishikawa and Shinya Sugiura, “Maximizing constrained capacity of power-imbalanced optical wireless MIMO communications using spatial modulation,” Journal of Lightwave Technology, vol. 33, no. 2, pp. 519–527, January 2015.
  34. Naoki Ishikawa and Shinya Sugiura, “Unified differential spatial modulation,” IEEE Wireless Communications Letters, vol. 3, no. 4, pp. 337–340, August 2014.