Faculty Profiles - MIYAMOTO Shinichi

Published Papers - MIYAMOTO Shinichi

Division display >> ／ All the affair displays1 - 89 of about 89

A Proposal of WLAN Systems Using a Virtual Dedicated Channel Scheme to Enhance High-throughput Transmission Opportunities

Shunsuke TSUTSUMI, Yusuke HIRANO, Shinichi MIYAMOTO （Part： Corresponding author )

The transactions of the Institute of Electronics, Information and Communication Engineers. B 108-B ( 3 ) 136 - 146 2025.03 [Refereed]

DOI

A study of secure communication with secret sharing method in MIMO eigen stream parallel channels

Masaaki Yamanaka, Shigenori Kinjo, Shinichi Miyamoto

IEICE Communications Express ( Institute of Electrical and Electronics Engineers (IEEE) ) 13 ( 3 ) 72 - 75 2024.03 [Refereed]

DOI

Distributed Transmission for Secure Wireless Links Based on a Secret-sharing Method

Masaaki Yamanaka, Wei Shencong, Zou Jingbo, Shuichi Ohno, Shinichi Miyamoto, Seiichi Sampei

IEICE Trans. on Commun. E102-B ( 12 ) 2286 - 2296 2019.12 [Refereed]

Dynamically Controlled Transmission Standby in WLAN Systems

Yukio Kojima, Shinichi Miyamoto

IEICE Communications Express 8 ( 6 ) 213 - 218 2019.03 [Refereed]

Transmission Standby based on Channel Conditions for Efficient Use of Radio Resources in WLAN Systems

Yukio Kojima, Shinichi Miyamoto

2018 Asia-Pacific Microwave Conference (APMC 2018) 165 - 167 2018.11 [Refereed]

Study on Secure Distributed Transmission in Two-way Wireless Communication Links

Masaaki Yamanaka, Zou Jingbo, Shuichi Ohno, Shinichi Miyamoto, Seiichi Sampei

5th IEEE GLOBECOM Workshop on Trusted Communications with Physical Layer Security 978 2017.12 [Refereed]

Millimeter-Wave Wireless LAN and Its Extension toward 5G Heterogeneous Networks

Kei Sakaguchi, Ehab Mahmoud Mohamed, Hideyuki Kusano, Makoto Mizukami, Shinichi Miyamoto, Roya E. Rezagah, Koji Takinami, Kazuaki Takahashi, Naganori Shirakata, Hailan Peng, Toshiaki Yamamoto, Shinobu Nanba

IEICE TRANSACTIONS ON COMMUNICATIONS ( IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG ) E98B ( 10 ) 1932 - 1948 2015.10 [Refereed] [Invited]

Millimeter-wave (mmw) frequency bands, especially 60 GHz unlicensed band, are considered as a promising solution for giga-bit short range wireless communication systems. IEEE standard 802.11ad, also known as WiGig, is standardized for the usage of the 60 GHz unlicensed band for wireless local area networks (WLANs). By using this mmw WLAN, multi-Gbps rate can be achieved to support bandwidth-intensive multimedia applications. Exhaustive search along with beamforming (BF) is usually used to overcome 60 GHz channel propagation loss and accomplish data transmissions in such mmw WLANs. Because of its short range transmission with a high susceptibility to path blocking, multiple number of mmw access points (APs) should be used to fully cover a typical target environment for future high capacity multi-Gbps WLANs. Therefore, coordination among mmw APs is highly needed to overcome packet collisions resulting from un-coordinated exhaustive search BF and to increase total capacity of mmw WLANs. In this paper, we firstly give the current status of mmw WLANs with our developed WiGig AP prototype. Then, we highlight the great need for coordinated transmissions among mmw APs as a key enabler for future high capacity mmw WLANs. Two different types of coordinated mmw WLAN architecture are introduced. One is distributed antenna type architecture to realize centralized coordination, while the other is autonomous coordination with the assistance of legacy Wi-Fi signaling. Moreover, two heterogeneous network (HetNet) architectures are also introduced to efficiently extend the coordinated mmw WLANs to be used for future 5th Generation (5G) cellular networks.

DOI

Wide Coverage Area Creation with Radiation-constraint Nodes Based on Distributed Radiation Suppression Using a Secret Sharing Method

Masaaki Yamanaka, Shinichi Miyamoto, Seiichi Sampei

情報処理学会論文誌 ( Information Processing Society of Japan (IPSJ) ) 56 ( 2 ) 460 - 469 2015.02 [Refereed]

The authors will propose a wide coverage area creation method in an indoor wireless communication environment with radiation-constraint wireless nodes within a condition that the transmitted information can only be conveyed in an indoor wireless space. The authors have proposed a radiation suppression technique to create such a highly secured indoor communication environment. However due to the strict limitation of the radiation constraint, the coverage area will be deeply shrunken when decent radio suppression cannot be attained at the node. This paper will propose a distributed radiation suppression technique using a secret sharing method to widen the coverage area of the indoor wireless network by relaxing the radiation constraint imposed on the wireless nodes. Computer simulation confirms that a wide coverage area can be created in an indoor wireless space while suppressing information leakage to the outside of the network.

Multi-Stage DCF-Based Channel Access Scheme for Throughput Enhancement of OFDMA WLAN Systems

Shinichi Miyamoto, Naoya Ikeshita, Seiichi Sampei, Wenjie Jiang

IEICE TRANSACTIONS ON COMMUNICATIONS ( IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG ) E97B ( 10 ) 2230 - 2242 2014.10 [Refereed]

To enhance the throughput of wireless local area networks (WLANs) by efficiently utilizing the radio resource, a distributed coordination function-based (DCF-based) orthogonal frequency division multiple access (OFDMA) WLAN system has been proposed. In the system, since each OFDMA sub-channel is assigned to the associated station with the highest channel gain, the transmission rate of DATA frames can be enhanced thanks to multi-user diversity. However, the optimum allocation of OFDMA sub-channels requires the estimation of channel state information (CSI) of all associated stations, and this incurs excessive signaling overhead. As the number of associated stations increases, the signaling overhead severely degrades the throughput of DCF-based OFDMA WLAN. To reduce the signaling overhead while obtaining a sufficient diversity gain, this paper proposes a channel access scheme that performs multiple DCF-based channel access. The key idea of the proposed scheme is to introduce additional DCF-based prioritized access along with the traditional DCF-based random access. lathe additional DCF-based prioritized access, by dynamically adjusting contention window size according to the CSI of each station, only the stations with better channel state inform their CSI to the access point (AP), and the signaling overhead can be reduced while maintaining high multi-user diversity gain. Numerical results confirm that the proposed channel access scheme enhances the throughput of OFDMA WLAN.

DOI

Group-based Centralized Radio Resource Management Strategies in Wireless Local Area Networks

Shinichi Miyamoto, Seiichi Sampei

2014 XXXITH URSI GENERAL ASSEMBLY AND SCIENTIFIC SYMPOSIUM (URSI GASS) ( IEEE ) 2014 [Refereed] [Invited]

To improve the transmission performance of wireless local area networks (WLANs), this paper proposes a distributed coordination function-based (DCF-based) medium access control (MAC) protocol that enables centralized radio resource management (RRM). In the protocol, AP and associated stations form a cooperative group, and the central controller acts as a master to organize the access of associated stations. Once the cooperative group reserves the radio resource in a traditional DCF-manner, the central controller allocates the reserved radio resources to the stations by an orthogonal frequency division multiple access (OFDMA) scheme. Since the central controller dynamically allocates the fine-grained resource blocks (RBs) to the stations through the opportunistic two-dimensional scheduling based on the channel and traffic conditions of each station, the transmission opportunities can be granted to the appropriate stations. Numerical results confirm that the proposed protocol enhance the throughput while satisfying QoS requirements.

Wide-area Centralized Radio Resource Management for DCF-based Multi-hop Ad hoc Wireless Networks

Shinichi Miyamoto, Naoki Hayata, Seiichi Sampei, Wenjie Jiang

2014 INTERNATIONAL CONFERENCE ON COMPUTING, NETWORKING AND COMMUNICATIONS (ICNC) ( IEEE ) 710 - 715 2014 [Refereed]

This paper proposes a novel medium access control (MAC) protocol that enables a wide area centralized radio resource management (RRM) in a distributed coordination function (DCF)-based multi-hop wireless network. In the proposed protocol, after the acquisition of transmission opportunity in a DCF-manner, a source station (STA) attempts to forward a medium reservation advertisement (MRA) frame to a destination STA. MRA forwarding enables multiple STAs constituting a multi-hop network to reserve the radio resource for their exclusive use throughout multi-hop wide area. MRA forwarding is also utilized to gather channel state information (CSI) and traffic state information (TSI) of STAs at the central controller that is adaptively selected from the STAs. After the MRA forwarding, based on the CSI and TSI of each STA, the central controller dynamically allocates the resource blocks (RBs) to the appropriate STAs through the opportunistic two-dimensional scheduling using OFDMA scheme. Assigned RB information is notified to STAs by relaying transmission schedule advertisement (TSA) frame, and the STAs send DATA frames on the allocated RBs. Numerical simulation confirms that the proposed scheme enhances the end-to-end throughput of multi-hop network.

Realization of Secure Ambient Wireless Network System Based on Spatially Distributed Ciphering Function

Masashi Okada, Masahide Hatanaka, Keiichiro Kagawa, Shinichi Miyamoto

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES ( IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG ) E96A ( 11 ) 2182 - 2184 2013.11 [Refereed]

This paper proposes a secure wireless network system required for an ambient information society; it forms a privacy zone wherein terminals can securely communicate secret information using an arbitrary general radio channel. For this system, we introduce a scheme using a side-information from a special node. The information is used as an encryption key so that the detectable region of the key defines a privacy zone. We implement the scheme on the basis of IEEE 802.15.4 and realize the world's first ambient network platform with the above functionality. An experiment and demonstration show the effectiveness of the proposed system.

DOI

Station clustering strategy for DCF-based centralized OFDMA WLAN systems

Takuya Endo, Shinichi Miyamoto, Seiichi Sampei, Wenjie Jiang

2013 International Conference on Connected Vehicles and Expo, ICCVE 2013 - Proceedings ( IEEE Computer Society ) 343 - 349 2013 [Refereed]

To enhance the throughput of orthogonal frequency division multiple access (OFDMA) wireless local area network (WLAN) systems, this paper proposes a stations-clustering strategy in which stations in the basic service set (BSS) are grouped into clusters. In the proposed scheme, initially, to obtain statistics required for calculating the expected throughput achieved by OFDMA WLAN when the stations are grouped into a certain clustered-pattern, the access point (AP) and all stations belong to the same cluster and transmit DATA frames for a certain period. After that, the AP calculates the expected throughput for all clustered-patterns and chooses a clustered-pattern that maximizes the expected throughput. Then, the stations are grouped into clusters in accordance with the selected clustered-pattern, and the stations within the same cluster share the radio resource by OFDMA WLAN scheme. Numerical simulation confirms that the proposed scheme can maximize throughput performance by introduction of dynamic station clustering in the single BSS environment and it is also effective in preventing channel state information (CSI) feedback blocking due to station exposition in the overlapping BSS environment. © 2013 IEEE.

DOI

Novel DCF-based Multi-User MAC Protocol and Dynamic Resource Allocation for OFDMA WLAN Systems

Takuya Mishima, Shinichi Miyamoto, Seiichi Sampei, Wenjie Jiang

2013 INTERNATIONAL CONFERENCE ON COMPUTING, NETWORKING AND COMMUNICATIONS (ICNC) ( IEEE ) 616 - 620 2013 [Refereed]

To enhance the throughput of wireless local area networks (WLANs) while satisfying the quality of service (QoS) requirements, this paper proposes a novel DCF-based multi-user MAC protocol employing orthogonal frequency division multiple access (OFDMA) scheme. In the proposed protocol, an access point (AP) acts as a master to organize all the stations within the basic service set (BSS) and reserves the radio resource by the conventional distributed coordination function (DCF). In the resource reservation period, the AP performs a flexible access control utilizing the fine-grained resource block and the opportunistic scheduling based on the QoS requirements and the channel condition of each station. With the objective to increase the spectrum efficiency as well as to satisfy the QoS requirements, this paper also proposes a dynamic resource allocation algorithm. Numerical results confirm that the proposed multi-user MAC protocol ensures the QoS requirement with a high probability and enhances the throughput performance.

Distributed transmission for secure wireless links in non-line-of-sight environment by joint transmitter-receiver beamforming

Masaaki Yamanaka, Shinichi Miyamoto, Seiichi Sampei

IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 724 - 728 2013 [Refereed]

The authors have proposed a distributed-transmission-based secure wireless link creation scheme by providing multiple transmission routes to a destination. In the proposed scheme, the transmitted information is divided into pieces of "shared information" by a secret-sharing method, and the pieces of information are separately transmitted to the destination through different transmission routes with individually controlled antenna directivities. In this paper, we focus on the performance of the proposed scheme in a non-line-of-sight (NLOS) propagation environment and propose a joint receiver beamforming in accordance with the controlled transmitter antenna directivity. The computer simulations clarify that the degree of spatial distribution of the transmission routes is enhanced by the joint beamforming. Therefore, it can improve the secrecy of the transmitted information by the distributed transmission in the wireless space. © 2013 IEEE.

DOI

Novel DCF-based multi-user MAC protocol for centralized radio resource management in OFDMA WLAN systems

Shinichi Miyamoto, Seiichi Sampei, Wenjie Jiang

IEICE Transactions on Communications ( Institute of Electronics, Information and Communication, Engineers, IEICE ) E96-B ( 9 ) 2301 - 2312 2013 [Refereed]

To enhance the throughput while satisfying the quality of service (QoS) requirements of wireless local area networks (WLANs), this paper proposes a distributed coordination function-based (DCF-based) medium access control (MAC) protocol that realizes centralized radio resource management (RRM) for a basic service set. In the proposed protocol, an access point (AP) acts as a master to organize the associated stations and attempts to reserve the radio resource in a conventional DCF-manner. Once the radio resource is successfully reserved, the AP controls the access of each station by an orthogonal frequency division multiple access (OFDMA) scheme. Because the AP assigns radio resources to the stations through the opportunistic two-dimensional scheduling based on the QoS requirements and the channel condition of each station, the transmission opportunities can be granted to the appropriate stations. In order to reduce the signaling overhead caused by centralized RRM, the proposed protocol introduces a station-grouping scheme which groups the associated stations into clusters. Moreover, this paper proposes a heuristic resource allocation algorithm designed for the DCF-based MAC protocol. Numerical results confirm that the proposed protocol enhances the throughput of WLANs while satisfying the QoS requirements with high probability. Copyright © 2013 The Institute of Electronics, Information and Communication Engineers.

DOI

Two-Stage DCF-based Access Scheme for Throughput Enhancement of OFDMA WLAN Systems

Kodai Shimamoto, Shinichi Miyamoto, Seiichi Sampei, Wenjie Jiang

15th International Conference on Wireless Personal Multimedia Communications (WPMC 2012) 584 - 588 2012.09 [Refereed]

A Novel Secure Wireless Communication Using Side Information from Spatially Distributed Nodes in Private Wireless Network

Kodai Shimamoto, Shinichi Miyamoto, Seiichi Sampei, Wenjie Jiang

15th International Conference on Wireless Personal Multimedia Communications (WPMC 2012) 453 - 457 2012.09 [Refereed]

DCF-based MAC Protocol for Centralized Radio Resource Management in OFDMA WLAN Systems

Takuya Mishima, Shinichi Miyamoto, Seiichi Sampei, Wenjie Jiang

9th IEEE Vehicular Technology Society Asia Pacific Wireless Communications Symposium (APWCS 2012) 2012.09 [Refereed]

A Study on a Transmit Antenna Directivity Control of Adaptive Array for Secure Wireless Transmission Based on the Multi-Path Routing

Masaaki Yamanaka, Norihiko Morinaga, Shinichi Miyamoto, Seiichi Sampei

2012 IEEE 75TH VEHICULAR TECHNOLOGY CONFERENCE (VTC SPRING) ( IEEE ) 1 - 5 2012 [Refereed]

This paper proposes an antenna directivity control method of adaptive array antenna for secure wireless transmission by dividing the transmitted information into pieces of divided-information and sending each pieces of information in a spatially distributed manner along multiple paths in a wireless space. Based on the DCMP weight control algorithm, the authors propose an antenna directivity control method not only to steer its main lobe to one targeted path but also to suppress other side lobes to suppress unnecessary signal radiation. Computer simulation confirms that by suppressing the side lobes of the antenna directivity, the transmitted signal power can be concentrated along the targeted path. It is effective to provide multiple transmission routes for signal delivery in the wireless space. Therefore better performance in regard with the secrecy of the transmitted information can be achieved in the wireless space by sending the transmitted information in a spatially distributed manner along the selected paths between the sender and the destination.

A study on a secure wireless link creation based on multi-path routing combined with transmit antenna directivity control

Masaaki Yamanaka, Norihiko Morinaga, Shinichi Miyamoto, Seiichi Sampei

Proceedings - 3rd IEEE International Conference on Intelligent Networking and Collaborative Systems, INCoS 2011 526 - 531 2011 [Refereed]

This paper proposes a secure wireless link creation scheme based on a multi-path routing in a single-hop wireless transmission environment, where multiple paths are created by directive transmission using the multipath component of wireless link which the link possesses naturally on its own. Moreover a secret sharing method is employed to divide the transmitted information into pieces of shared information and sending each pieces of information separately through the multiple paths. Computer simulation clarifies that with the proposed scheme, information recovery of the transmitted information can be confined to a limited area in the wireless space, i.e., the transmitted information is less exposed to the adversary around the legitimate terminals. © 2011 IEEE.

DOI

Intensity distribution based space and time division multiple access technique for hybrid-LOS indoor optical wireless communication

Shinichi Miyamoto, Kenji Kawamoto, Seiichi Sampei

FREE-SPACE LASER COMMUNICATION TECHNOLOGIES XXII ( SPIE-INT SOC OPTICAL ENGINEERING ) 7587 7587-31 2010 [Refereed]

This paper proposes a space division and time division multiple access (SD/TDMA) technique based on intensity distributions for hybrid line-of-sight (hybrid-LOS) indoor optical wireless communication system. At first, a novel signal discrimination scheme for the spatially multiplexed optical signals is proposed and it is applied to a space division multiple access (SDMA) in hybrid-LOS system. In the proposed scheme, multiple terminals simultaneously transmit their optical signals to access point (AP) using on-off-keying (OOK) modulation, and the spatially multiplexed optical signals are received by a photodetectors array (PD-array), where multiple PDs are disposed to observe the spatial intensity distribution of optical signals. Because the terminals transmit their data using OOK modulation, the spatial intensity distribution observed by the AP equipped with PD-array is subject to the data transmitted from individual terminals, and the AP can identify the terminals transmitting the optical signal by determining the transmitted intensity distribution. Of course, the transmitted intensity distributions are not orthogonal signal and the discriminability of transmitted intensity distributions is much related to the differences of intensity distributions. This implies that the number of terminals that can simultaneously access to the AP will be limited and it is determined by the differences of the candidate intensity distributions. In order to enhance the discriminability of the transmitted intensity distributions, the proposed signal discrimination scheme is further applied to the SD/TDMA. In the SD/TDMA, the discriminability required to enable SDMA is ensured by introducing a scheduling algorithm in which terminals with higher discriminatory of transmitted intensity distributions are allocated to the same time slot. Numerical results show that SD/TDMA using proposed signal discrimination scheme increases the throughput and the number of terminals that can access to the AP.

DOI

VLSI design of OFDM baseband transceiver with dynamic spectrum access

Masahide Hatanaka, Ryoji Hashimoto, Toshimitsu Tatsuka, Takao Onoye, Hironobu Hatamoto, Shinsuke Ibi, Shinichi Miyamoto, Seiichi Sampei

ISPACS 2010 - 2010 International Symposium on Intelligent Signal Processing and Communication Systems, Proceedings 329 - 332 2010 [Refereed]

The VLSI design of OFDM baseband transceiver is described, which is dedicated to cognitive radio systems. To facilitate dynamic spectrum accessing, this receiver architecture employs a specialized FFT module and a mapping/demapping module. Efficient mechanisms to omit input/output of unused subcarriers are introduced. Also, calculation of spectrum intensity for subcarrier level carrier sensing is successfully integrated to the FFT module. Whole transmitter/receiver modules are implemented by maintaining compatibility with IEEE 802.11g. Implementation results show that the proposed architecture can process OFDM symbols in 60 MHz operation. © 2010 IEEE.

DOI

Dynamic Subcarrier Selection Technique for Cognitive Wireless Mesh Networks Using CSMA/CA

Shinichi Miyamoto, Yuichi Goda, Seiichi Sampei

2008 International Workshop on Smart Info-Media Systems in Bangkok (SISB 2008) 81 - 86 2009.03 [Refereed]

Implementation of OFDM baseband transceiver with dynamic spectrum access for cognitive radio systems

Ryoji Hashimoto, Toshimitsu Tatsuka, Masahide Hatanaka, Takao Onoye, Hironobu Hatamoto, Shinsuke Ibi, Shinichi Miyamoto, Seiichi Sampei

2009 9th International Symposium on Communications and Information Technology, ISCIT 2009 658 - 663 2009 [Refereed]

VLSI architecture for OFDM base-band transceiver is developed, which is dedicated to cognitive radio systems. To facilitate dynamic spectrum access, this transceiver architecture employs a specialized FFT/IFFT module and a mapping/demapping module. Efficient mechanisms to omit input/output of unused subcarriers are introduced. Also, calculation of spectrum intensity for subcarrier level carrier sensing is successfully integrated to the FFT module. Whole transmitter/receiver modules are implemented by keeping compatibility with IEEE 802.11g. A prototype system is constructed by using Xilinx Virtex-II FPGA, which can transmit video sequence in real time. ©2009 IEEE.

DOI

Proposal of dynamic subcarrier selection technique using CSMA/CA for cognitive wireless mesh networks

Shinichi Miyamoto, Yuichi Goda, Seiichi Sampei

BROADBAND ACCESS COMMUNICATION TECHNOLOGIES III ( SPIE-INT SOC OPTICAL ENGINEERING ) 7234 7234-5 2009 [Refereed] [Invited]

In wireless mesh networks using unlicensed radio frequency band, how to adaptively and efficiently allocate spectrum among multiple wireless nodes according to the surrounding environment is an important issue. Cognitive radio that includes functionalities of radio environmental awareness and intelligent radio resource management in an opportunistic way is regarded as the great candidate to enable the efficient utilization of radio resource. In order to fully exploit radio resources and enhance spectrum efficiency based on cognitive radio to wireless mesh networks, this paper proposes dynamic subcarrier selection technique and CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) based MAC layer protocol for wireless mesh networks. In the proposed technique, based on the detection of available spot-wise subcarriers using the subcarrier-level carrier sense and the estimation of channel conditions, data packet is transmitted using unused discrete subcarriers having good channel conditions. Numerical results confirm that the proposed dynamic subcarrier selection technique is effective in utilizing radio resources and enhance spectrum efficiency. Moreover, because multiple nodes can get the transmission opportunity at the same time, the degradation in transmission performance due to the contention between multiple nodes can be solved.

DOI

Performances of 2.4GHz-band Wireless LAN Systems using Adaptive Multi-code Transmission Technique

Kazuhiro Watanabe, Shinichi Miyamoto, Norihiko Morinaga

電子情報通信学会論文誌 J85-B ( 12 ) 2209 - 2222 2008.11 [Refereed]

A Transmit Antenna Directivity Control Technique for Secure Data Transmission in Ubiquitous Communication Environments

Masaaki Yamanaka, Norihiko Morinaga, Seiichi Sampei, Shinichi Miyamoto

11th International Symposium on Wireless Personal Multimedia Communication (WPMC’08) 2008.09 [Refereed]

Spectrum loading type dynamic spectrum allocation technique for cognitive radio systems

Seiichi Sampei, Shinichi Miyamoto, Shinsuke Fbi

2007 2ND INTERNATIONAL CONFERENCE ON COGNITIVE RADIO ORIENTED WIRELESS NETWORKS AND COMMUNICATIONS ( IEEE ) 535 - 539 2007 [Refereed]

This paper proposes a spectrum loading type dynamic spectrum control technique for broadband cognitive radio systems. In the proposed scheme, based on the detection of available spot-wise spectra, discrete spectrum components of a framed symbol sequence are mapped onto the spot-wise spectra. Two spectrum mapping schemes are proposed; single-RF scheme in which available spot-wise spectra are located so close that the entire spot-wise spectra can be covered by an FFT/IFFT with a reasonable number of FFT points, and multi-RF scheme in which the spot-wise spectra are located far away so that the entire spectra cannot be covered by an FFT/IFFT processor. Computer simulation confirms that the proposed scheme is effective in utilizing spot-wise spectra. Moreover, the proposed scheme is confirmed to be effective in enhancement of co-channel and inter-symbol interference immunity when the number of opportunistically available spot-wise spectra is increased.

Unnecessary power radiation suppression technique using a transmit antenna directivity control in ubiquitous communication environments

Masaaki Yamanaka, Norihiko Morinaga, Seiichi Sampei, Shinichi Miyamoto

2007 IEEE 18TH INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR AND MOBILE RADIO COMMUNICATIONS, VOLS 1-9 ( IEEE ) 1643 - + 2007 [Refereed]

This paper will propose an unnecessary radiation power suppressing technique to electromagnetically restricted areas in ubiquitous communication environments. An adaptive array antenna is employed in each terminal to control a directivity of transmit antenna not to radiate unnecessary power to the electromagnetically restricted areas while keeping sufficient gain to a target terminal. To identify angle of departures to the electromagnetically restricted areas, a radio power sensor network is assumed. Moreover, channel sounding based delay profile estimation is conducted to identify the strongest path direction for the desired signal. Based on the identified strongest path for the desired signal and the direction of the unwanted radiation detected using the radio power sensor network, artificial delay profile for a transmitted signal is created, and antenna directivity for the transmitted signal is created using a deep and wide null creation technique based on the artificial delay profile. Computer simulation confirms that the unnecessary radiation to the electromagnetically restricted areas is sufficiently suppressed while keeping throughput at a satisfactory level.

Proposal of electromagnetic environment-aware wireless network using multi-hop wireless network system

Takashi Tamura, Shinichi Miyamoto, Seiichi Sampei

2006 IEEE INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY, VOLS 1-3, PROCEEDINGS ( IEEE ) 53 - 57 2006

This paper proposes an electromagnetic environment-aware multi-hop wireless network system to achieve a good balance between electromagnetic environment and communications environment. In the proposed system, adaptive transmission route selection and transmission power control are employed to satisfy the requirements concerning the electromagnetic environment-aware. To fuerther enhance throughput, we have introduced transmission rate control in addition to the adaptive route selection and transmission power control. Comuputer simulation confirms that the proposed system is effective to achieve a good balance between electromagnetic environment and communications environment.

Adaptive Channel Selection Technique for Dual-band Wireless LAN System

Proceedings of 2005 Wireless Personal Multimedia Communications 2005

Performance of 2.4GHz-band wireless LAN system using orthogonal frequency division multiplexing scheme under microwave oven noise environment

S Miyamoto, S Harada, N Morinaga

EMC 2005: IEEE International Symposium on Electromagnetic Compatibility, Vols 1-3, Proceedings ( IEEE ) 157 - 162 2005

2.4GHz-band wireless LAN system based on IEEE 802.11g standard has been taking a great attention as it provides the attractive features such as low cost and high speed transmission rate up to 54 Mbps using Orthogonal Frequency Division Multiplexing (OFDM) transmission scheme. However, 2.4GHz radio frequency band is also used for Industrial, Scientific and Medical (ISM) devices, and the man-made noise leaked from ISM devices will degrade the performance of 2.4GHz-band wireless LAN system. In this paper, we investigate the performances of 2.4GHz-band Wireless LAN system based on IEEE 802.11g standard (IEEE 802.11g WLAN system) under microwave oven noise environment. Numerical results show that the performances of IEEE 802.11g WLAN system are much degraded by the influence of man-made noise emitted from microwave oven.

DOI

Performance of 2.4GHz-band Wireless LAN System with IEEE 802.11e Polling Based Channel Access under Man-made Noise Environment

Proceeding of Pan-Pacific EMC Joint Meeting 2005 2005

Adaptive Packet Transmission Technique for 2.4GHz-band Wireless LAN System under Bluetooth Coexistence Environment

2004 Korea-Japan AP/EMC/EMT Joint Conference 2004

Dynamic Band Selection Technique for Dual-band Wireless LAN System

2004 Korea-Japan AP/EMC/EMT Joint Conference 2004

Adaptive multi-code transmission with adaptive multilevel modulation for 2.4 GHz-band wireless LAN systems

K Watanabe, S Miyamoto, N Morinaga

ELECTRONICS LETTERS ( IEE-INST ELEC ENG ) 39 ( 1 ) 168 - 169 2003.01 [Refereed]

DOI

Parameter estimation and bit error rate of optimum receiver in a class-A impulsive radio noise environment

H Kanemoto, S Miyamoto, N Morinaga

ELECTRONICS AND COMMUNICATIONS IN JAPAN PART I-COMMUNICATIONS ( SCRIPTA TECHNICA-JOHN WILEY & SONS ) 86 ( 8 ) 68 - 78 2003 [Refereed]

Since most of the noise generated by electronic equipment using high-frequency devices has statistical properties that are quite different from Gaussian noise, the bit error rate of conventional receivers is greatly degraded in a man-made noise environment, because they are designed with the presumption of Gaussian noise. One of the methods of providing a better bit error rate in such a noise environment is the use of an optimum receiver. This optimum receiver attains a high bit error rate by using maximum likelihood symbol detection based on the statistical properties of the noise, and the statistical properties of the noise must be known a priori for optimum reception. In this paper, we use the Middleton class-A impulsive radio noise model as the statistical model of the noise and study the parameter estimation and bit error rate of an optimum receiver in a class-A impulsive radio noise environment. First, we evaluate the effect of errors in parameter estimation on the bit error rate of the optimum receiver in a class-A impulsive radio noise environment, and show that to improve the performance of the optimum receiver in this noise environment, we should use parameters that express the statistics of the noise. Next we study the relationship between the number of noise samples used in estimation and the parameter estimation accuracy, and demonstrate that large numbers of noise samples are needed for highly accurate parameter estimation. However, it is shown that a quite good bit error rate can be obtained by the optimum receiver in the noise environment even if parameter estimation is based on a somewhat smaller number of noise samples (for example, about 700 samples for an impulsive index A = 0.05 and a Gaussian component ratio Gamma' = 0.05). (C) 2003 Wiley Periodicals, Inc.

DOI

A Proposal of the Indoor Infrared Wireless LAN System using Infrared Wireless Repeater

MIYAOKA Katsuya, MIYAMOTO Shinichi, MORINAGA Norihiko

ITE Technical Report ( The Institute of Image Information and Television Engineers ) 26 45 - 50 2002

A directed line-of-sight (LOS) system achives the highest speed communication by directional control of transmitter and receiver in the indoor infrared wireless LAN system. However, for utilizing a LOS chanel between transmitter and receiver, the performance is affected by the partition. In this paper, we discuss the probability of terminal accommodation and the transmission power in the environment with the partition and propose the system using some infrared wireless repeaters in order to reduce a loss with the partition. These results lead to validity of the proposed system by decreasing effect of a loss with the partition.

DOI

Adaptive Immunity Control of 2.4GHz-band DS-SS Wireless LAN System under Man-made Noise and Multipath Fading Environment

Shinichi Miyamoto, Norihiko Morinaga

2001 Asia-Pacific Radio Science Conference (AP-RASC'01) E6-05 2001.08 [Refereed] [Invited]

Performance of 2.4GHz-band DS-SS Wireless LAN System using Adaptive Multicode Transmission under Man-made Noise Environment

Kazuhiro Watanabe, Shinichi Miyamoto, Norihiko Morinaga

Progress In Electromagnetic Research Symposium (PIERS 2001) 601 2001.07 [Refereed]

Adaptive Multicode Transmission Technique in 2.4GHz-band DS-SS Wireless LAN System

Shinichi Miyamoto, Norihiko Morinaga

5th World Multi Conference on Systemics, Cybernetics and Informatics (SCI 2001) IS00305-5 2001.07 [Refereed]

Performance of 2.4GHz-band DS-SS Wireless LAN System using Adaptive Multicode Transmission

Kazuhiro Watanabe, Shinichi Miyamoto, Norihiko Morinaga

11th Virginia Tech MPRG Symposium on Wireless Personal Communications 43 - 48 2001.06 [Refereed]

A Study on the Performance of 2.4 GHz Band DS-SS Wireless LAN System using Adaptive Multicode Transmission

Proceedings of the 2001 IEICE General Conference 69 - 70 2001

Multiple-beams Transmission and Multiple-detectors Reception for PPM/CDMA based Non-directed Diffuse Indoor Infrared Wireless Communication System

Takahiro Yamane, Shinichi Miyamoto, Kazutoshi Hirohashi, Norihiko Morinaga

Fifth Optoelectronics and Communications Conference (OECC 2000) 238 - 239 2000.07 [Refereed]

EMI suppression technique for ISM-band WLANs using multicode transmission and EMI observation channel

S Unawong, S Miyamoto, N Morinaga

IEICE TRANSACTIONS ON COMMUNICATIONS ( IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG ) E83B ( 3 ) 532 - 540 2000.03 [Refereed]

It is well known that the electromagnetic interference (EMI) radiated from industrial, scientific and medical (ISM) apparatus seriously degrades the performance of wireless communication systems. In this paper, an ISM-band wireless local area network (WLAN) which employs a direct sequence spread spectrum (DS-SS) system is designed to be sufficiently robust and reliable to operate in the presence of this EMI. To satisfy this goal, a technique to suppress EMI in the DS-SS system using a multicode transmission and an EMI observation channel is proposed. In the study, thf EMI radiated from switching-type microwave ovens (MWO interference) which are ISM apparatus is concerned, and for a tractable investigation, a statistical model to represent MWO interference based on experimental measure ment results is employed. As well known that MWO interference exhibits a bursty impulsive characteristic in time, a technique to transmit multiple long spreading codes (multicode transmission) is introduced for the DS-SS system to overcome the burstness of the interference. Moreover, inspired by the broadband in frequency of MWO interference, a technique to estimate the channel MWO interference by means of observing its levels in an adjacent channel is proposed, and this technique is applied to construct a multicode DS-SS receiver which can suppress the channel MWO interference. An evaluation of the Lit error rate performance of the proposed multicode DS-SS system is conducted bg computer simulation, and the numerical results demonstrate that the proposed DS-SS system can operate effectively even in the presence of MWO interference.

Angle Diversity Reception technique with CNR Estimation under Man-made Noise and Multipath Fading Environments

TOU S.

Proceedings of ISAP2000 1565 - 1568 2000

Indoor Optical Wireless Local Area Network Systems

Optics ( 5 ) 139 - 143 2000

Overlapped Zone Construction for Hybrid Line-of-Sight Indoor Infrared Wireless Communication System

Fifth Optoelectronics and Communication Conference(OECC2000)Technical Digest 240 - 241 2000

A Proposal of Adaptive Multicode Transmission for DS-SS System under ISM Interference Environments

Sakda Unawong, Shinichi Miyamoto, Norihiko Morinaga

1999 Asia-Pacific Microwave Conference 186 - 189 1999.12 [Refereed]

CNR Estimation under Man-made Noise Environment and Its Application to Noise Reduction Technique using Sector Antenna

Shinichi Miyamoto, Kensuke Yoshizawa, Norihiko Morinaga

1999 Asia-Pacific Microwave Conference 190 - 193 1999.12 [Refereed]

Indoor Wireless Local Area Network System using Infrared and Radio Communications

Shinichi Miyamoto, Yoshiyasu Hirayama, Norihiko Morinaga

1999 Asia-Pacific Conference on Communications 790 - 793 1999.10 [Refereed]

Zone Construction for PPM/CDMA-Based Non-Directed Line-of-Sight Indoor Infrared Wireless Communication System

Makoto Funabiki, Shinichi Miyamoto, Kazutoshi Hirohashi, Norihiko Morinaga

10th International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'99) 726 - 730 1999.09 [Refereed]

Multiple Zone Construction and Countermeasure against Shadowing for Non-Directed Line-of-Sight Indoor Infrared Wireless Communication System

Yoshiyasu Hirayama, Shinichi Miyamoto, Masahisa Sakai, Norihiko Morinaga

10th International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'99) 831 - 835 1999.09 [Refereed]

Angle Diversity Reception in ISM-band Wireless LAN Systems under Man-made Noise Environment

Kensuke Yoshizawa, Shinichi Miyamoto, Norihiko Morinaga

10th International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'99) 731 - 735 1999.09 [Refereed]

A novel receiver design for DS-CDMA systems under impulsive radio noise environments

S Unawong, S Miyamoto, N Morinaga

IEICE TRANSACTIONS ON COMMUNICATIONS ( IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG ) E82B ( 6 ) 936 - 943 1999.06

In this paper, we investigate the bit error rate (BER) performance of Direct Sequence-Code Division Multiple Access (DS-CDMA) systems under impulsive radio noise environments, and propose a novel DS-CDMA receiver which is designed to be robust against impulsive noise. At first, employing the Middleton's Class-A impulsive noise model as a typical model of impulsive radio noise, we discuss the statistical characteristics of impulsive radio noise and demonstrate that the quadrature components of impulsive noise are statistically dependent. Next, based on the computer simulation, we evaluate the BER performance of a conventional DS-CDMA system under a Class-A impulsive noise environment, and illustrate that the performance of the conventional DS-CDMA system is drastically degraded by the effects of the impulsive noise. To deal with this problem, motivated by the statistical dependence between the quadrature components of impulsive radio noise, we propose a new DS-CDNA receiver which can eliminate the effects of the channel impulsive noise. The numerical result shows that the performance of the DS-CDMA system under the impulsive noise environment is significantly improved by using this proposed receiver. Finally to confirm the effectiveness of this proposed receiver against actual impulsive radio noise, we evaluate the BER performance of the DS-CDMA system employing the proposed receiver under a microwave oven (MWO) noise environment and discuss the robustness of the proposed receiver against MWO noise.

Man-made Noise Reduction Scheme Using Sector Antenna in Digital Radio Communication System

Kensuke Yoshizawa, Shinichi Miyamoto, Norihiko Morinaga

International Symposium on Electromagnetic Compatibility (EMC'99/Tokyo) 670 670 - 673 1999.05 [Refereed]

The BCH Coded Digital Radio Communication System under Man-made Noise Environments

Sakda Unawong, Shinichi Miyamoto, Norihiko Morinaga

International Symposium on Electromagnetic Compatibility (EMC'99/Tokyo) 321 - 324 1999.05 [Refereed]

Application of chip-interleaving and blanker for DS-SS system under microwave oven interference environment

S Unawong, S Miyamoto, N Morinaga

ELECTRONICS LETTERS ( IEE-INST ELEC ENG ) 35 ( 9 ) 695 - 696 1999.04

DOI

A Study on Parameter Estimation and Error Rate Performance of Optimum Receiver under Class-A Impulsive Radio Noise Environment

KANEMOTO Hideki, MIYAMOTO Shinichi, MORINAGA Norihiko

ITE Technical Report ( The Institute of Image Information and Television Engineers ) 23 ( 24 ) 79 - 86 1999.03

In order to improve true error rate performance under radio frequency man-made noise enviroment, optimum reception based on the statistical characteristics of man-made noise has been proposed. In this optimum reception, the statistical characteristics of mam-made noise have to be estimated in advance. In this paper, we employ Middleton's class-A impulsive noise model as a statistical model of man-made noise, and discuss the parameter estimation of class-A model and the performance of optimum receiver constructed with estimated parameters. Numerical results show that, although the enormous amount of noise sample is required to obtain precise estimated parameters, a good error performance of optimum receiver can be obtained with parameters estimated by a certain amount of noise sample.

DOI

Performance of digital radio communication system with BCH coding under microwave oven interference

H Kanemoto, S Miyamoto, N Morinaga

ELECTRONICS LETTERS ( IEE-INST ELEC ENG ) 34 ( 15 ) 1465 - 1466 1998.07

DOI

A Study on the Performance of Non-directed Line-of Sight Indoor Optical Wireless Communication System using PPM/CDMA

FUNABIKI Makoto, MIYAMOTO Shinichi, MORINAGA Norihiko

ITE Technical Report ( The Institute of Image Information and Television Engineers ) 22 ( 11 ) 7 - 12 1998.02

Code division multiple access (CDMA) scheme is a current subject of great interest as a multiple access scheme for indoor optical wireless communication system. In this paper, we discuss the performance of line-of-sight indoor optical wireless communication system using PPM/CDMA scheme. At first, we evaluate the downlink and uplink performances and show that, because of multiple access interference, the number of accommodated terminals and the coverage area are much restricted. In order to obtain the large number of accommodated terminals and large coverage area, we propose a new zone construction method which divides the communication channels spatially. Numerical results conclude that the number of accommodated terminals and coverage area can be much improved by using proposed zone construction.

DOI

Statistical model of microwave oven interference and optimum reception

H Kanemoto, S Miyamoto, N Morinaga

ICC 98 - 1998 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS VOLS 1-3 ( IEEE ) 1660 - 1664 1998 [Refereed]

Microwave oven interference seriously degrades the performance of digital radio communication systems, therefore, in order to obtain a good error performance under microwave oven interference environment, the digital radio communication systems should be newly designed for this environment. In this paper, using the Middleton's canonical class-A impulsive noise model, we propose a statistical model of microwave oven interference and discuss the performance improvement achieved by an optimum reception based on this statistical model. Numerical results conclude that the first order statistic of microwave oven interference can be modeled by class-A impulsive radio noise, and the great performance improvement is obtained by using the optimum receiver designed against microwave oven interference with sample interleave scheme.

A study on modeling of microwave oven interference and optimum reception

H Kanemoto, S Miyamoto, N Morinaga

1998 IEEE INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY - SYMPOSIUM RECORD, VOLS 1 AND 2 ( IEEE ) 1 57 - 62 1998

The performance of digital radio communication systems is much degraded by the effect of microwave, oven interference, therefore, in order to obtain a good error performance under microwave oven interference environment, the digital radio communication systems should be newly designed for this environment. In this paper; using the Midleton's canonical class-A impulsive noise model, we propose a statistical model of microwave oven interference and discuss the performance improvement achieved hv rut optimum reception based on this statistical model. As the results. the first order statistic of microwave oven interference call he modeled by class-A impulsive radio noise, and the great performance improvement is obtained hy using: the optimum receiver designed against microwave oven interference with sample interleave scheme.

Performance Improvement of Digital Radio Communication System against Man-made Noise by Sector Antenna

Proceedings of the 1998 Asia-Pacific Microwave Conference 3 1215 - 1218 1998

Effects of microwave oven interference on the performance of ISM-band DS/SS system

S Unawong, S Miyamoto, N Morinaga

1998 IEEE INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY - SYMPOSIUM RECORD, VOLS 1 AND 2 ( IEEE ) 1 51 - 56 1998

In this paper, we investigate the effects of microwave oven (MWO) interference on the performance of ISM-band Direct-Sequence/Spread-Spectrum(DS/SS) system: and propose the techniques for improving the system performance. The computer simulation results show that in the presence of MWO interference, the performance of the conventional DS/SS system is severely degraded by the effects of the interference. To deal with this problem, motivated by the statistical characteristics of the interference, we propose a chips-interleaving method and a new receiver, designing for DS/SS system under MWO interference environment. It is demonstrated that an improvement in performance can be obtained by using the interleaving together with this proposed receiver.

Zone Construction of Non-directed Line-of-Sight Indoor Optical Wireless Communication System for High Spectrum Efficiency

Proceedings of the OECC'98 222 - 223 1998

Performance of Digital Radio Communication System with BCH Coding under Man-made Noise Environment

Proceedings of the 1998 Asia-Pacific Microwave Conference 3 1219 - 1222 1998

Techniques to improve the performance of wireless LAN under ISM interference environments

S. Unawong, S. Miyamoto, N. Morinaga

5th Asia-Pacific Conference Communications and 4th Optoloelectronics Communications Conference: The Conference-Vitality to New Century, APCC/OECC 1999 ( Institute of Electrical and Electronics Engineers Inc. ) 1 802 - 805 1998

It is well known that wireless local area networks (WLANs), operating in industrial, scientific and medical bands (900 MHz, 2400 MHz, and 5700 MHz ), can be seriously affected by electromagnetic interference radiated from ISM apparatus. In this paper, to improve the bit error performance of a direct-sequence spread-spectrum (DS-SS) system which is employed, in an ISM-band WLAN under ISM interference environments, we propose a multicode transmission technique and a method to observe ISM interference. Computer simulation results demonstrate that the DS-SS system employing the proposed techniques can obtain a good performance even in the presence of ISM interference.

DOI

Study of the effect of microwave oven interference on the performance of digital radio communications systems

Shinichi Miyamoto, Yukio Yamanaka, Takashi Shinozuka, Norihiko Morinaga

Electronics and Communications in Japan, Part I: Communications (English translation of Denshi Tsushin Gakkai Ronbunshi) ( Scripta Technica Inc ) 80 ( 12 ) 58 - 68 1997.12

With increasing use of wireless communication systems and electronic equipment using high-frequency devices, a poor electromagnetic environment for wireless communication systems is expected. This paper discusses the microwave oven, which is a widely used ISM apparatus. The effect of the interference waves generated by a microwave oven on the bit error characteristics of various wireless communication systems (PDC, PHS, ISM band wireless LAN) is studied. First, based on the measured interference waves generated from various microwave ovens, the statistical nature of the interference waves is discussed. It is found that a high level interference wave with periodicity is generated from microwave ovens and that the level and duration of the interference wave increase as the oscillation frequency of the magnetron is approached. Next, the bit error rates of π/4 shift QDPSK and DS/CDMA systems are simulated on a computer. It is found that the bit error rate is changed substantially by the effect of the interference wave. Further, for the case where the TDMA system is used as a multiple access system, a channel assignment method based on the periodicity of the interference wave is proposed. It is clear that the bit error rate can be improved significantly by using the proposed channel assignment method.

DOI

Proposal of Non-directed Diffuse Indoor Optical Wireless Communication System with Multi-beam Repeater

Kimihiko Imamura, Shinichi Miyamoto, Norihiko Morinaga

1997 Pacific Rim Conference on Lasers and Electro-Optics (CLEO/Pacific Rim '97) 104 1997.07 [Refereed]

Modeling of microwave oven interference using class-A impulsive noise and optimum reception

H Kanemoto, S Miyamoto, N Morinaga

IEICE TRANSACTIONS ON COMMUNICATIONS ( IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG ) E80B ( 5 ) 670 - 677 1997.05 [Refereed]

Microwave oven interference much degrades the performance of digital radio communication systems, and, in order to obtain a good error performance under microwave oven interference environment, the digital radio communication systems should be newly designed for microwave oven interference environment. In this paper, using the Middleton`s canonical class-A impulsive noise model, Lye propose a statistical model of microwave oven interference and discuss the performance improvement achieved by an optimum reception based on this statistical model. As the results, although the first order statistic of microwave oven interference can be modeled by class-A impulsive noise. because of the burst high level interference, the performance of optimum receiver designed for class-A noise cannot achieve a good error performance under microwave oven interference environment. In order to eliminate the effect of burst high level interference, we introduce sample interleave scheme and show that the performance of optimum receiver can be much improved by using sample interleave scheme.

A Study on Non-directed Line-of-Sight Optical Wireless Communication System

MIYANAGA Kenji, MIYAMOTO Shinichi, MORINAGA Norihiko

ITE Technical Report ( The Institute of Image Information and Television Engineers ) 21 ( 12 ) 47 - 52 1997.02

As an indoor wireless communication system, a line-of-sight (LOS) optical communication system has been taking a great attention. In the conventional LOS system, the communication area is covered only one transmitter and then the conventional LOS system is mainly used as the point-to-point or broadcast communication system. In this paper, by using the narrowness of optical beam width, we propose a zone construction method and discuss the increase of capacity by dividing communication channel spatially. Numerical results conclude that the capacity of LOS system with proposed zone construction is much increased compared to that of conventional one.

DOI

A Study on Non-directed Diffuse Optical Wireless Communication System with Transmitter-Receiver Diversity

MORIOKA Souhei, MIYAMOTO Shinichi, MORINAGA Norihiko

ITE Technical Report ( The Institute of Image Information and Television Engineers ) 21 ( 12 ) 41 - 46 1997.02

As an indoor wireless communication system, a non-directional diffuse optical wireless communication system has been taking a great attention. In this system, however, to achive a large cavarage transmission, we have to use a transmitter with wide beams and a receiver with wide field-of-views (FOV's). Therefor, when we communicate with multi transmitter-receiver pairs in a room, the transmitter-receiver pairs interfere with each other. In this paper, to achive communication with multi transmitter-receiver pairs, we propose transmitter-receiver diversity system, and discuss the performance of the proposed system. This paper indicates the probability of communication with multi transmitter-receiver pairs.

DOI

Receiver design of CDMA system for impulsive radio noise environment

S Unawong, S Miyamoto, N Morinaga

1997 INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY, PROCEEDINGS ( I E E E ) 316 - 319 1997

This paper is devoted to the investigation on the performance of DS/CDMA system under impulsive radio noise environment. At first, by using the Middleton's class-A impulsive noise model, we evaluate the performance of conventional DS/CDMA system under impulsive radio noise and it is shown that the performance of conventional DS/CDMA system is much degraded by the effect of impulsive noise. Next using the dependence between quadrature components of impulsive radio noise, we propose the receiver designed for impulsive noise and evaluate the performance improvement achieved by this receiver. Moreover, in order to confirm the effectiveness of proposed receiver for actual impulsive radio noise, Re evaluate the performance of proposed receiver under microwave oven interference environment. Numerical results conclude that the performance of DS/CDMA system is much improved by using proposed receiver.

Performance of radio communication systems under microwave oven interference environment

S Miyamoto, N Morinaga

1997 INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC COMPATIBILITY, PROCEEDINGS ( I E E E ) 308 - 311 1997

In this paper, the effect of microwave oven interferences to the performance of several digital radio communications systems (PDC, PHS, ISM-band Wireless LAN) is investigated. At first, Re measure the interferences emitted from microwave ovens and it is shown that high level interferences are emitted from microwave ovens and its emission interval is matched with a cycle of powerline. By using the measurement results. the performance of pi/4-shift QDPSK and DS/CDMA systems are evaluated. Numerical results show that the performance of pi/4-shift QDPSK is much degraded by the effect of microwave oven interference. Moreover. it is shown that, for the case of TDMA multiple access scheme, since the high level interferences are emitted periodically, a specified channel suffers from the high level interferences.

Effect of microwave oven interference on the performance of digital radio communications systems

S Miyamoto, N Morinaga

ICC'97: 1997 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS - TOWARDS THE KNOWLEDGE MILLENNIUM, CONFERENCE RECORD - VOLS 1-3 ( I E E E ) 51 - 55 1997

In this paper, we investigate the effects of microwave ovens interference on the performance of digital radio communications systems (PDC, PHS, ISM-band wireless LAN). At first, we experimentally measure the interference radiated from microwave ovens and discuss the statistical characteristics of interference. Then, by using the measurements results, the effects of interference on the performance of pi/4-shift QDPSK and DS/CDMA systems are evaluated. Numerical results conclude that the performance of digital radio communication systems are significantly degraded by the effect of interference. Moreover, ave propose a new TDMA channel assign method for microwave oven interference and investigate the performance improvement achieved by proposed channel assign.

A Study on the Effect of Microwave Oven Interference to the Performance of Digital Radio Communications Systems

Shinichi Miyamoto, Yukio Yamanaka, Takashi Shinozuka, Norihiko Morinaga

電子情報通信学会論文誌 J79-B-II ( 2 ) 140 - 145 1996.02 [Refereed]

Effect of microwave oven interferences to the performance of personal handy-phone system

S Miyamoto, Y Yamanaka, T Shinozuka, N Morinaga

1996 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS - CONVERGING TECHNOLOGIES FOR TOMORROW'S APPLICATIONS, VOLS. 1-3 ( I E E E ) 3 1457 - 1461 1996

A proposal of multi beam transmitter for non-directed diffuse indoor optical wireless communication system

K Nishida, S Miyamoto, K Tsukamoto, N Morinaga

PIMRC'96 - THE SEVENTH IEEE INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR AND MOBILE RADIO COMMUNICATIONS, PROCEEDINGS, VOLS 1-3 ( I E E E ) 242 - 246 1996

For future high speed indoor wireless communication, a non-directed diffuse optical wireless communication system attracts a great attention. In this paper, in order to obtain enough received signal power for nondirected diffuse optical wireless communication system, a multi beam transmitter system is proposed and the performance improvement achieved by proposed system is evaluated. Numerical results show that high received signal power can be obtained by using the multi beam transmitter and the performance of proposed system is much better than that of conventional non-directed diffuse system. Moreover, we evaluate the effect of delay spread to the performance of proposed system and it is confirmed that the great performance improvement is achieved by suppressing the delay spread.

Characteristics of Electromagnetic Disturbance from Microwave Ovens and the Interference with Digital Radio Communication Systems

Takashi Shinozuka, Yukio Yamanaka, Shinichi Miyamoto, Norihiko Morinaga

1995 International Symposium on Communications (ISCOM'95) 2 769 - 776 1995.12 [Refereed]

PERFORMANCE ANALYSIS OF QAM SYSTEMS UNDER CLASS-A IMPULSIVE NOISE ENVIRONMENT

S MIYAMOTO, M KATAYAMA, N MORINAGA

IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY ( IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC ) 37 ( 2 ) 260 - 267 1995.05 [Refereed]

This paper describes the performance of QAM (Quadrature Amplitude Modulation) systems under impulsive noise environment. In the analysis, we employ, as a model of the impulsive noise, Middleton's model labeled class A. First, the statistical characteristics of the in-phase and quadrature components of the impulsive noise are investigated, and it is proved that, in contrast to Gaussian noise, these components are dependent especially for the impulsive noise with small impulsive indices. Nest, with consideration of the dependence between the in-phase and quadrature components of the noise, the performance of QAM systems with the conventional receiver designed for Gaussian noise is analyzed, The numerical results show that the performance is much worse than that achieved under Gaussian noise, Moreover, we show the design of the maximum Likelihood receiver for class A impulsive noise and the great performance improvement by this receiver is confirmed.

DOI

DESIGN OF TCM SIGNALS FOR CLASS-A IMPULSIVE NOISE ENVIRONMENT

S MIYAMOTO, M KATAYAMA, N MORINAGA

IEICE TRANSACTIONS ON COMMUNICATIONS ( IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG ) E78B ( 2 ) 253 - 259 1995.02

In this paper, a design of TCM signals for Middleton's class-A impulsive noise environment is investigated. The error event characteristics under the impulsive noise is investigated, and it is shown that the length of the signal sequence is more important than Euclidean distance between the signal sequences. Following this fact, we introduce the shortest error event path length as a measure of the signal design. In order to make this value large, increasing of states of convolutional codes is employed, and the performance improvement achieved by this method is evaluated. Numerical results show the great improvement of the error performance and conclude that the shortest error event path length is a good measure in the design of TCM signals under impulsive noise environment. Moreover, the capacity of class-A impulsive noise channel is evaluated, and the required signal sets expansion rates to obtain the achievable coding gain is discussed.

Design of TCM Signals for Class-A Impulsiev Noise Environment

Shinichi Miyamoto, Norihiko Morinaga （Part： Lead author )

Proceedings of the 11th International Zurich Symposium and Technical Exhibition on Electromagnetic Compatibility 143 - 148 1995

Electromagnetic Disturbance above 1GHz and its effect to the Performanceof Digital Radio Communications Systems

Vol.8, No.92, pp.50-60 1995

Performance of CDMA System under Class-A Impulsive Noise Environment

Proceeding of 2nd Asia-Pacific Conference on Communications 331 - 335 1995

Receiver design using the dependence between quadrature components of impulsive radio noise

S MIYAMOTO, M KATAYAMA, N MORINAGA

ICC '95 - 1995 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, CONFERENCE RECORD, VOLS 1-3 ( I E E E ) ( 3 ) 1784 - 1789 1995

A Design of BPSK Receiver Using the Dependence between Quadrature Components of Class-A Impulsive Noise

Proceedings of the 1994 International Symposium on Electromagnetic Compatibility 513 - 516 1994

OPTIMUM DETECTION AND DESIGN OF TCM SIGNALS UNDER IMPULSIVE NOISE ENVIRONMENT

S MIYAMOTO, M KATAYAMA, N MORINAGA

IEEE INTERNATIONAL CONFERENCE ON SYSTEMS ENGINEERING ( I E E E ) 473-478 473 - 478 1992

　PREV-NEXT　

<MIYAMOTO Shinichi>

Published Papers - MIYAMOTO Shinichi