Publications

H. So, K. Yoshizawa, T. Fujita, and Y. Asai, ``Experimental evaluation of multi-link operations for wireless LAN with different link characteristics,'' IEICE Transaction on Communications, (2026.2.24 Accepted)

H. Soya, D. Iijima, and H. So, “AGV path selection method considering communication information,” EURASIP Journal on Wireless Communications and Networking (JWCN), (2026.2.19 Accepted)

H. So, “Field measurement of UAV radio propagation in continuously changing construction site environments,” IEICE Transaction on Communications, Vol.E109-B, No.4, pp., Apr. 2026. (2025.10.10 Accepted) doi: 10.23919/transcom.2025WWP0006

G.K. Tran, J. Nakazato, K. Suto, H. So, and H. Iwamoto, “Research on smart wireless aerial networks facilitating digital twin construction,” IEICE Transaction on Communications, Vol. E109-B, No. 4, pp.–, Apr. 2026.(2025.10.6 Accepted) doi: 10.23919/transcom.2025SCI0001

H. So, K. Maruta, and T. Kaho, “Joint fast beam search and synchronization using fast switching phased array,” IEEE Transactions on Vehicular Technology (TVT), vol. 75, no. 3, pp. 4278–4288, Mar. 2026. doi: 10.1109/TVT.2025.3609286

H. Soya, K. Inagaki, and H. So, “A flight route design method considering multi-hop communication using delivery UAVs,” Drones, vol. 9, no. 11, p. 751, pp. 1–15, Oct. 2025. doi: 10.3390/drones9110751

H. So, K. Maruta, and Y. Nakayama, “Adaptive C-RAN architecture using crowdsourced radio units for smart city,” IEEE Access, vol. 11, pp. 81124–81133, Aug. 2023. doi: 10.1109/ACCESS.2023.3301143

H. So, T. Kaho, Y. Yamamoto, M. Suga, Y. Takahashi, Y. Shirato, and N. Kita, “Staircase array antenna with stacked butler matrix for concurrent multi-beams,” IEEE Access, vol. 11, pp. 76638–76646, Aug. 2023. doi: 10.1109/ACCESS.2023.3297659

H. So and H. Soya, “Excluded channel selection scheme for dynamic spectrum sharing in various interference environments,” IEEE Access, vol. 11, pp. 69798–69806, July 2023. doi: 10.1109/ACCESS.2023.3292837

H. So, “Migratory unmanned aerial vehicle system (MiUAV) for automated infrastructure inspection,” IEEE Access, vol. 11, pp. 56392–56399, June 2023. doi: 10.1109/ACCESS.2023.3282995

Y. Nakayama, H. So, E. Takeshita, and K. Maruta, “Gamified participatory D2D communication for encouraging user participation toward future mobile communication,” IEEE Access, vol. 10, pp. 81269–81280, Aug. 2022. doi: 10.1109/ACCESS.2022.3195341

H. So and H. Soya, “Two-step channel observation scheme considering spread of observation results in dynamic spectrum sharing,” IEEE Open Journal of Vehicular Technology (OJVT), vol. 3, pp. 367–374, July 2022. doi: 10.1109/OJVT.2022.3192737

H. So and K. Maruta, “Sector design using multiband antenna with metamaterial reflector for cellular UAV system,” IEEE Access, vol. 10, pp. 4924–4933, Jan. 2022. doi: 10.1109/ACCESS.2022.3140780

H. So and D. Murayama, “Efficient immediate-transmission scheme for emergency packets in closed area wireless access networks,” IEEE Access, vol. 9, pp. 168236–168244, Dec. 2021. doi: 10.1109/ACCESS.2021.3137303

H. So, K. Fukawa, H. Soya, and Y. Chang, “Metric-combining multiuser detection using replica cancellation with RTS and enhanced CTS for high-reliable and low-latency wireless communications,” IEICE Transaction on Communications, vol. E104-B, no. 11, pp. 1441–1453, Nov. 2021. doi: 10.1587/transcom.2020EBP3150

H. So, H. Soya, and K. Fukawa, “Spectrum sensing scheme measuring packet lengths of interfering systems for dynamic spectrum sharing,” IEEE Access, vol. 9, pp. 135160–135166, Oct. 2021. doi: 10.1109/ACCESS.2021.3116951

H. So and K. Maruta, “Directional antenna with lightweight metamaterial reflector for UAV-based networks,” IEEE Access, vol. 9, pp. 78735–78741, June 2021. doi: 10.1109/ACCESS.2021.3084235

H. So, T. Fujita, K. Yoshizawa, M. Naya, and T. Shimizu, “Highly reliable radio access scheme by duplicate transmissions via multiple frequency channels and suppressed useless transmission under interference from other systems,” IEICE Transaction on Communications, vol. E104-B, no. 6, pp. 696–704, June 2021. doi: 10.1587/transcom.2020EBP3046

H. So, K. Suzaki, and D. Goto, “Undesired radiation suppression technique with adaptive control for distributed array antenna systems in mobile environment,” Journal of Communications Software and Systems (JCOMSS), vol. 16, no. 2, pp. 163–169, June 2020. doi: 10.24138/jcomss.v16i2.1044

H. So, K. Maruta, and K. Suzaki, “Laboratory experiment of blind adaptive array with subcarrier transmission power assignment in spectrum superposing scenarios,” Electronics, vol. 7, no. 1, Jan. 2018. doi: 10.3390/electronics7010007

D. Goto, F. Yamashita, K. Suzaki, H. So, Y. Suzuki, K. Kobayashi, and N. Kita, “Evaluations for estimation method of the distributed array antenna (DAA) radiation pattern by experimental analysis,” IEICE Transactions on Communications, vol. E101-B, no. 6, pp. 1494–1502, June 2018. doi: 10.1587/transcom.2017EBP3154

K. Suzaki, H. So, D. Goto, Y. Suzuki, F. Yamashita, K. Nakahira, K. Kobayashi, and T. Sugiyama, “Undesired radiation suppression technique for distributed array antenna by antenna positioning and delay signal processing,” IEICE Transactions on Communications, vol. E100-B, no. 10, pp. 1959–1967, Oct. 2017. doi: 10.1587/transcom.2016EBP3374

H. So, A. Ando, T. Seki, M. Kawashima, and T. Sugiyama, “Multiband sector antenna with the same beamwidth employing multiple woodpile metamaterial reflectors,” IEICE Transaction on Electronics, vol. E97-C, no. 10, pp. 976–985, Oct. 2014. doi: 10.1587/transele.E97.C.976

H. So, “Optimal relay positions in cooperative UAV relay networks,” IEICE Communications Express (ComEX), vol. 14, no.7, pp. 287–291, July 2025. doi: 10.23919/comex.2025XBT0001

H. So and H. Soya, “Evaluation of shadowing effect on channel observation for spectrum sharing access,” IEICE Commun. Express, vol. 13, no. 9, pp. 379–383, Sep. 2024. doi: 10.23919/comex.2024XBL0106

S. Ozawa, T. Ikuta, Y. Sasaki, R. Iwaki, J. Nakazato, M. Tsukada, H. So, and K. Maruta, “Location-aided fast beam tracking algorithm for millimeter-wave V2I,” IEICE Communications Express (ComEX), vol. 13, no. 5, pp. 146–150, May 2024. doi: 10.23919/comex.2024XBL0001

H. So, T. Kaho, Y. Yamamoto, Y. Takahashi, M. Suga, Y. Shirato, and N. Kita, “A proposal on V-shape staircase array antenna with stacked Butler matrix,” IEICE Communications Express (ComEX), vol. 12, no. 4, pp. 114–119, Apr. 2023. doi: 10.1587/comex.2022XBL0172

H. So, A. Matsumoto, and K. Haruta, “Concept of migratory unmanned aerial vehicle system (MiUAV) for automated infrastructure inspection,” IEICE Communications Express (ComEX), vol. X11-B, no. 12, pp. 805–810, Dec. 2022. doi: 10.1587/comex.2022COL0022

H. So, T. Kaho, M. Suga, T. Arai, Y. Shirato, H. Toshinaga, D. Uchida, and N. Kita, “Novel staircase array antenna configuration using stacked Butler matrix for low profile base station,” IEICE Communications Express (ComEX), vol. X11-B, no. 6, pp. 279–283, Jun. 2022. doi: 10.1587/comex.2022SPL0009

H. So, “Symmetrical small trapezoid dipole antenna for broadband wireless communications,” IEICE Communications Express (ComEX), vol. X11-B, no. 6, pp. 252–256, Jun. 2022. doi: 10.1587/comex.2022SPL0001

K. Cho, H. So, and A. Ando, “HPBW control of dipole antenna with frequency selective reflector using different size elements,” IEICE Communications Express (ComEX), vol. 5, no. 3, pp. 90–94, Feb. 2016. doi: 10.1587/comex.2015XBL0184

H. So, A. Ando, T. Seki, M. Kawashima, and T. Sugiyama, “Directional multi-band antenna employing frequency selective surfaces,” Electronics Letters, vol. 49, no. 4, pp. 243–245, Feb. 2013. doi: 10.1049/el.2012.4263

T. Kazama, K. Fukue, H. So, and K. Maruta, “Software Radio-based Laboratory Experiment of Blind Adaptive Array Interference Suppression for LTE-WLAN Spectrum Superposing,” in Proc. IEEE International Conference on Computer Communications 2026 (INFOCOM 2026), Apr. 2026.

K. Inagaki, H. Soya, and H. So, “Flight path determination method for building a communication platform using delivery UAVs,” in Proc. The 40th International Conference on Information Networking (ICOIN2026), Jan. 2026.

D. Iijima, H. Soya, and H. So, “A study on AGV path determination method considering communication information,” in Proc. The 40th International Conference on Information Networking (ICOIN2026), Jan. 2026.

Wembo Xu, J. Nakazato, H. So, and M. Hasegawa, “Multi-agent reinforcement learning for UAV relay deployment in 3D space,” in Proc. The 40th International Conference on Information Networking (ICOIN2026), Jan. 2026.

K. Fukue, T. Kazama, H. So, S. Kojima, and K. Maruta, “Adaptive BAA Switching by CNN-Based Spectrogram Learning in LTE/WLAN Coexistence,” in Proc. 2026 IEEE 23rd Consumer Communications & Networking Conference (IEEE CCNC 2026), Jan. 2026.

T. Kazama, K. Fukue, H. So, and K. Maruta, “Demonstration of blind adaptive array signal processing for LTE-WLAN spectrum superposing,” in Proc. 2026 IEEE 23rd Consumer Communications & Networking Conference (IEEE CCNC 2026), Jan. 2026.

H. So and K. Maruta, “Evaluation of cell ID detection by phase rotation with fast beam steering,” in Proc. 2026 IEEE 23rd Consumer Communications & Networking Conference (IEEE CCNC 2026), Jan. 2026.

S. Umeda, K. Nakayama, K. Ishioka, H. So, N. Yoneda, A. Taira, S. Yoshima, and T. Suehiro, “Spatial extraction technology using terahertz-wave imaging,” in Proc. The 6th IEICE-CS International Conference on Emerging Technologies for Communications (ICETC2025), P2-08, Nov. 2025.

H. So, T. Yoshida, S. Umeda, K. Ishioka, N. Yoneda, and A. Taira, “Performance evaluation of terahertz-based posture detection using skeletal detection for slip-and-fall risk monitoring,” in Proc. The 6th IEICE-CS International Conference on Emerging Technologies for Communications (ICETC2025), P2-06, Nov. 2025.

H. Soya and H. So, “A study on improving user throughput using cell clustering method in dynamic TDD system,” in Proc. The 6th IEICE-CS International Conference on Emerging Technologies for Communications (ICETC2025), P1-03, Nov. 2025.

K. Fukue, T. Kazama, H. So, S. Kojima, and K. Maruta, “CNN-based SIR estimation using spectrogram in LTE-WLAN coexistence environment,” in Proc. The 30th Asia-Pacific Conference on Communications (APCC2025), W3-2.3, Nov. 2025.

H. So, N. Kuno, S. Saito, T. Murakami, and S. Suyama, “Technical overview and trend for integrated sensing and communications (ISAC),” in Proc. 21st IEEE VTS Asia Pacific Wireless Communications Symposium (APWCS 2025), pp. 1–5, Aug. 2025. doi: 10.1109/APWCS67981.2025.11151911.

H. So and J. Nakazato, “Evaluation of radio interference considering actual user distribution in urban UAV delivery,” in Proc. IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW2025), July 2025. doi: 10.1109/ICCE-Taiwan66881.2025.11207772

H. So, K. Maruta, and Y. Nakayama, “Throughput evaluation in actual user distribution for adaptive C-RAN with crowdsourced radio unit,” 2025 IEEE 101st Vehicular Technology Conference (VTC2025-Spring), pp. 1–5, June 2025. doi: 10.1109/VTC2025-Spring65109.2025.11174431

T. Kazama, H. Ikeda, H. So, and K. Maruta, “Blind adaptive array interference suppression in LTE-WLAN coexistence environment,” 2025 IEEE 101st Vehicular Technology Conference (VTC2025-Spring), pp. 1–5, June 2025. doi: 10.1109/VTC2025-Spring65109.2025.11174608

Y. Murakami, Y. Sugimoto, H. So, and T. Murakami, “Detection and identification of overlapping cards using terahertz imaging,” in Proc. 19th European Conference on Antennas and Propagation (EuCAP) 2025, pp. 1–4, Mar. 2025. doi: 10.23919/EuCAP63536.2025.10999644

H. So and J. Nakazato, “[WIP] UAV autonomous control using multi-agent reinforcement learning in a cooperative control UAV network,” in Proc. 2024 International Conference on Intelligent Computing and ITS Emerging Application (ICEA2024), pp. 109–110, Nov. 2024. doi: 10.1145/3732437.3732739

K. Inagaki, H. Soya, and H. So, “A study on multi-hop data transmission using drones in disaster situations,”, in Proc. The 5th IEICE-CS International Conference on Emerging Technologies for Communications (ICETC2024), vol. 85, P3-05, Nov. 2024.

D. Iijima, H. Soya, and H. So, “Throughput evaluation by estimating the number of effective interfering STAs in tight-lattice environment,”, in Proc. The 5th IEICE-CS International Conference on Emerging Technologies for Communications (ICETC2024), vol. 85, P3-04, Nov. 2024.

H. So, “Evaluation of radio interference areas by flight path and antenna directivity of UAV in urban area,” in Proc. 2024 IEEE 100th Vehicular Technology Conference (VTC2024-Fall), pp. 1–5, Oct. 2024. doi: 10.1109/VTC2024-Fall63153.2024.10757864.

K. Maruta, J. Nakazato, K. Suzuki, H. Dou, R. Iwaki, S. Ozawa, Y. Sasaki, H. So, and M. Tsukada, “Millimeter-wave fast beam tracking enabled by RAN/V2X cooperation,” in Proc. The Sixth International Conference on AI in information and communication (ICAIIC 2024), pp. 388–392, Feb. 2024. doi: 10.1109/ICAIIC60209.2024.10463482.

H. So, K. Maruta, and T. Kaho, “Concept of Joint Fast Beam Search and Synchronization Scheme using Fast Beam Steering,” in Proc. The Sixth International Conference on AI in information and communication (ICAIIC 2024), pp. 7–10, Feb. 2024. doi: 10.1109/ICAIIC60209.2024.10463342.

M. Mizuto, H. So, K. Maruta, and Y. Nakayama, “Penalized approach for wide coverage in gamifed participatory D2D communication,” in Proc. The 36th International Conference on Information Networking (ICOIN 2022), A-6-3, Jan. 2022.

Y. Kakizaki, T. Ohtsuki, P. Kam, K. Suzaki, H. Sasaki, and H. So, “Joint SDA-MAP estimation of channel and interference power in superposed OFDM transmission,” in Proc. 2017 IEEE Global Communications Conference (GLOBECOM 2017), pp. 1–6, Dec. 2017. doi: 10.1109/GLOCOM.2017.8254794

A. B. Al-Shaikh, F. H. Panahi, T. Ohtsuki, K. Suzaki, H. Sasaki, H. So, and T. Nakagawa, “Q-learning based superposed band detection in multicarrier transmission,” in Proc 2017 IEEE International Conference on Communications (ICC 2017), pp. 1–6, May 2017. doi: 10.1109/ICC.2017.7997432

H. So, K. Maruta, J. Mashino, and K. Suzaki, “Experimental verification of spectrum superposing in two different systems by blind adaptive array with subcarrier transmission power assignment,” in Proc. 2016 IEEE 84th Vehicular Technology Conference (VTC2016-Fall), Sept. 2016. doi: 10.1109/VTCFall.2016.7881007

Y. Tanizawa, K. Cho, H. So, and A. Ando, “[Invited] Radiation characteristics of corner reflector antenna employing frequency selective surface,” in Proc. 2016 URSI Asia-Pacific Radio Science Conference (URSI AP-RASC 2016), S-B1-6, Aug. 2016.

Y. Tanizawa, K. Cho, H. So, and A. Ando, “Element shape of FSR backed dipole antenna suitable for obtaining sector radiation pattern,” in Proc. 2015 International Workshop on Electromagnetics: Applications and Student Innovation Competition (iWEM 2015), PO2.3, Nov. 2015. doi: 10.1109/iWEM.2015.7365058

H. So, A. Ando, T. Sugiyama, and K. Cho, “Design for suppressing undesired reflections from frequency-selective surfaces employed in multiband sector antenna,” in Proc. 2015 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (AP-S/URSI 2015), pp. 824–825, July 2015. doi: 10.1109/APS.2015.7304799

K. Cho, Y. Tanizawa, H. So, A. Ando, and T. Sugiyama, “Influence of FSR element shape on FSR backed dipole antenna applied to mobile base station antenna,” in Proc. 2015 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (AP-S/URSI 2015), July 2015.

K. Cho, H. So, A. Ando, and T. Sugiyama, “Consideration of FSR element shape for use in FSR backed dipole antenna,” in Proc. 2014 IEEE Asia-Pacific Conference on Applied Electromagnetics (APACE 2014), pp. 4–7, Dec. 2014. doi: 10.1109/APACE.2014.7043806

H. So, A. Ando, and T. Sugiyama, “Dual-band nested waveguide antenna employing frequency-selective surfaces,” in Proc. 2014 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (AP-S/URSI 2014), pp. 2080–2081, July 2014. doi: 10.1109/APS.2014.6905367

H. So, K. Fukawa, S. Suyama, and H. Suzuki, “Channel estimation for MIMO-OFDM systems employing minimum BER-based precoding under co-channel interference,” in Proc. The International Workshop on Millimeter Wave Wireless Technology and Applications, P-1, Dec. 2010.

H. So, K. Fukawa, S. Suyama, and H. Suzuki, “Channel estimation for MIMO-OFDM systems employing minimum BER precoding under co-channel interference,” in Proc. 15th International OFDM Workshop (InOWo 2010), pp. 36–40, Sept. 2010.