{"title":"Overview of C-NAT and Its Reinforcement for IoT Data Exchange Platform","authors":"Atsuko Yokotani;Horoshi Mineno;Masaki Mitsuuchi;Koichi Ishibashi;Tetsuya Yokotani","doi":"10.23919/comex.2024COL0012","DOIUrl":"https://doi.org/10.23919/comex.2024COL0012","url":null,"abstract":"IoT platforms have been actively discussed for deploying various IoT services using a horizontal approach. The IoT Data Exchange Platform (IoT-DEP) is one of these platforms, standardized as ISO/IEC 30161 series in ISO/IEC JTC 1/SC 41. These standardized documents specify the requirements, architecture, and functional blocks of the communication components. However, detailed communication sequences among the communication components are considered an implementation issue. This paper proposes a content-centric network with Network initiative And Traffic control (C-NAT) applied to the IoT-DEP as a promising candidate for communication sequences. Moreover, it proposes the reinforcement of C-NAT for low-latency and reliable industrial services when applied to IoT-DEP. Specifically, although the original C-NAT is intended to provide cyclic communication, this study proposes support for non-cyclic communication in reinforced C-NAT.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 12","pages":"492-495"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713855","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"2-Step Robust DNN Model for RSSI-Based Indoor Localization","authors":"Taisei Kosaka;Steven Wandale;Koichi Ichige","doi":"10.23919/comex.2024XBL0165","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0165","url":null,"abstract":"In this paper, we introduce a novel approach called the 2-Step Robust Deep Neural Network (DNN), designed specifically for indoor localization utilizing received signal strength indicator (RSSI) data. This method represents an advancement over the previously proposed 2-Step Extreme Gradient Boosting (XGBoost), aiming to enhance estimation precision by leveraging a single coordinate (\u0000<tex>$x$</tex>\u0000 or \u0000<tex>$y$</tex>\u0000) as a feature. The pivotal alterations involve transitioning from XGBoost to DNN and refining the training data to develop a resilient learning model for positional coordinates. Through comprehensive simulations, we demonstrate that the proposed 2-Step Robust DNN attains superior estimation accuracy while preserving the absence of constraints on the dataset.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 12","pages":"513-516"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713854","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Study of MACKEY for Multi Band with Asymmetric Structure","authors":"Hayato Ide;Toru Fukasawa;Shimpei Akimoto;Shigeru Makino","doi":"10.23919/comex.2024ATL0008","DOIUrl":"https://doi.org/10.23919/comex.2024ATL0008","url":null,"abstract":"MACKEY (Meta-surface inspired Antenna Chip developed by KIT EOE Laboratory) has been proposed as a functional compact antenna that is not affected by surrounding metals. Parallel placement of two MACKEYs has also been proposed for Wi-Fi 2GHz and Wi-Fi 5GHz bands. However, the MACKEY parallel arrangement type has a large width Land requires two feeding points to excite each patch. In this report, we present the analysis and measurements results of the miniaturized multi frequency MACKEY, which is a modification of the conventional type for Wi-Fi 2GHz and Wi-Fi 5GHz bands.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"14 2","pages":"43-46"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713512","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optimal Power Allocation for Secure Transmission in Untrusted Relay Networks with Alamouti Space-Time Block Coding","authors":"Shen Qian","doi":"10.23919/comex.2024XBL0140","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0140","url":null,"abstract":"This work explores the impact of optimal power allocation on the physical layer security of lossy decode-and-forward untrusted relay networks using Alamouti Space-Time Block Code (STBC). We introduce the reliable-and-secure probability (RSP) metric to measure the likelihood of successful message recovery at the destination while ensuring the message remains unintelligible to the relays. In high spectral efficiency scenarios, allocating more power to the untrusted relay significantly enhances the RSP, surpassing low spectral efficiency results. A balanced power allocation between the source and the relay, with Alamouti STBC, achieves a high RSP. However, the peak RSP is achieved when the power contributions from the source and the relay are balanced.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 12","pages":"496-499"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713858","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yukio Toyoshima;Tomoya Hatano;Tatsuya Shimada;Tomoaki Yoshida
{"title":"Dynamic Hardware Accelerator Selection Achieving Optimal Utilization of Resources","authors":"Yukio Toyoshima;Tomoya Hatano;Tatsuya Shimada;Tomoaki Yoshida","doi":"10.23919/comex.2024XBL0152","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0152","url":null,"abstract":"Edge computing with offloading over a network is being considered for enabling users to use advanced applications such as autonomous control applications. When network transmission time and/or task-processing time change, the total offloading time also varies. To guarantee low latency of offloading service in this case, over-performance hardware accelerator (HWA) must be assigned on edge computing, which leads to inefficient HWA resource allocation. To address this issue, we propose a method of selecting a HWA corresponding to change of the network transmission time and/or task-processing time. The proposed method refers past transmission times and input data size for the offload, enabling the prediction of changes in network transmission time and/or task-processing time. We evaluated the time for offloading through simulation and found that our method achieves a high percentage of offloads requested by users while efficiently using HWAs.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 12","pages":"504-508"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713510","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dynamic Mobile X-Haul Reconfiguration by Fast Network Switching for Low-Latency MEC Service","authors":"Takumi Harada;Tatsuya Shimada;Tomoaki Yoshida","doi":"10.23919/comex.2024XBL0135","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0135","url":null,"abstract":"The architectural flexibility of the Radio Access Network (RAN) is expected to be enhanced by applying Network Function Virtualization (NFV) to realize low-latency Multi-access Edge Computing (MEC). In order to provide on-demand MEC service tailored to the user's demands, RAN and the optical network should be constructed quickly without service interruption. In this paper, we propose a network and RAN control method that ensures cooperation of the network controller and RAN controller. It can switch network and RAN at the same time by simple reconfiguration. We evaluate the service interruption time by using the proposed method in some experimental setups in a comparison with the existing method. Finally, we confirm the proposed method enables faster reconfiguration than the network operator method.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 12","pages":"500-503"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713511","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Three-Dimensional Balun with a Bent Non-Contact Connector","authors":"Ryunosuke Murofushi;Nobuhiro Kuga;Eiji Hanayama","doi":"10.23919/comex.2024ATL0011","DOIUrl":"https://doi.org/10.23919/comex.2024ATL0011","url":null,"abstract":"We propose a three-dimensional balun with a balanced non-contact connector in this letter. Both measurement and simulation results show that the proposed connector has good reflection below −20 dB and transmission of almost 0 dB over a 14.6% fractional bandwidth in the 2 GHz band.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"14 2","pages":"51-54"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713857","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improvement of Angular Dependence of Angular Profile in DOA Measurement Method using Rotating Reflector Antenna","authors":"Toshiki Hozen;Kazuma Tomimoto;Tomonori Ikeda;Ryo Yamaguchi","doi":"10.23919/comex.2024ATL0012","DOIUrl":"https://doi.org/10.23919/comex.2024ATL0012","url":null,"abstract":"In next-generation mobile communications, the proactive use of millimeter-wave and terahertz-wave frequencies, which can secure a wide frequency bandwidth, is anticipated. The authors reported a measurement method using a rotating reflector antenna to realize high-speed direction-of-arrival (DOA) measurement by rotating a large-aperture antenna at these frequencies. The authors previous method adopted a circularly polarized antenna as the primary radiator to accommodate the polarization rotation of the antenna. However, this method had the issue of angular dependence in the angular profile. To solve this problem, this paper proposes a measurement method that uses an orthogonally polarized antenna as the primary radiator of a rotating reflector antenna for rotational measurements, and processes the acquired data offline. To confirm the effectiveness of the proposed method, a demonstration experiment is conducted in an anechoic chamber, and it is shown that an angular profile with less angular dependence can be obtained than using a circularly polarized antenna as the primary radiator. We also show that the proposed method is capable of fast DOA measurement.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"14 2","pages":"47-50"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713509","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"QRD-Based Precoding Design for Multiuser Massive MIMO Null-Space Expansion","authors":"Yuki Sasaki;Kabuto Arai;Kazuki Maruta","doi":"10.23919/comex.2024XBL0150","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0150","url":null,"abstract":"This article proposes a precoding weight suitable for null-space expansion (NSE) in multi-user massive multiple-input multiple-output (MU-mMIMO). NSE improves inter-user interference (IUI) suppression performance by steering multiple nulls for interfering user terminals (UTs). However, NSE faces challenges in effectively forming beams and nulls for IUI suppression, as well as in managing the computational complexity for precoding. We employ QR decomposition-based Gram-Schmidt orthogonalization (QRGSO) as a precoding algorithm suitable for NSE. Computer simulation demonstrates the superiority of the proposed scheme in terms of IUI suppression performance and computation complexity.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 12","pages":"509-512"},"PeriodicalIF":0.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10713513","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Preamble Detection Method for RSS Data Synchronization in WLAN Monitoring","authors":"Morihiko Tamai;Akio Hasegawa;Hiroyuki Yokoyama","doi":"10.23919/comex.2024XBL0134","DOIUrl":"https://doi.org/10.23919/comex.2024XBL0134","url":null,"abstract":"Received signal strength (RSS) data is one of the useful data types for understanding wireless link quality. To perform WLAN monitoring over a wide area of the target environment, it is necessary to use multiple sensor nodes to observe RSS data at various positions. In this situation, achieving synchronization among sensor nodes is challenging. In this paper, we propose a synchronization method for different sets of RSS data. In our method, by analyzing In-phase and Quadrature (IQ) samples, the preamble, which is part of a wireless frame, is detected, and the reception start timing of each preamble is used as a synchronization timing point. Through experiments in an actual indoor environment, we confirmed that our method can achieve the synchronization accuracy of less than 1 µs between different sets of RSS data.","PeriodicalId":54101,"journal":{"name":"IEICE Communications Express","volume":"13 11","pages":"435-439"},"PeriodicalIF":0.3,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10675420","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142600160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}