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Effect of the Interference Canceler on the Nonorthogonal CSK/CDMA ALOHA
Nobuyoshi KOMURO,Hiromasa HABUCHI,Toshinori TSUBOI 대한전자공학회 2008 ITC-CSCC :International Technical Conference on Ci Vol.2008 No.7
Nonorthogonal Code Shift Keying Code Division Multiple Access (CSK/CDMA) ALOHA is expected to improve the throughput in advanced wireless network, such as sensor networks and ad-hoc networks. The throughput of the nonorthogonal CSK/CDMA ALOHA is expected to get better by introducing interference cancellation technique. It is not clear how much the throughput improved by introducing interference canceler. This paper presents the throughput performance of the nonorthogonal CSK/CDMA ALOHA with interference canceler by theoretical analysis. Consequently, it is found that the throughput performance of our system is over 1.0. It is also found that the throughput performance shows more than 295 % increase by using the interference canceler when Eb/No is high.
Design and Analysis of Multi-Channel MAC Protocol with Channel Grouping in Wireless Ad-Hoc Networks
KOMURO, Nobuyoshi,MANZOKU, Ryo,SANADA, Kosuke,MA, Jing,LI, Zhetao,PEI, Tingrui,CHOI, Young-June,SEKIYA, Hiroo 'Institute of Electronics, Information and Communi 2016 IEICE TRANSACTIONS ON COMMUNICATIONS - Vol.eb99 No.11
Nonorthogonal CSK/SS ALOHA System under MANET Environment
Nobuyoshi Komuro,Hiromasa Habuchi 한국통신학회 2021 ICT Express Vol.7 No.4
Spread ALOHA systems that combine the spread spectrum techniques with the ALOHA system (a simple random access protocol without carrier sensing function) have been investigated as Mobile Ad-hoc Network (MANET) protocols. This paper presents the effect of the nonorthogonal Code Shift Keying Spread Spectrum (CSK/SS) ALOHA system on improving the throughput and delay performances of the spread ALOHA system under the MANET environment. The nonorthogonal CSK/SS system, which uses systematically-constructed nonorthogonal sequences, is one of the multilevel modulation systems for the spread spectrum technique with increasing the number of bits per frame. Optimum parameters can be used to obtain the best system performance; thus, this paper gives analytical expressions of the data transmission efficiency and delay property of the proposed scheme as a function of the system parameters under the assumption of no power control. Numerical results show that the nonorthogonal CSK/SS ALOHA system is useful in the MANET environment, compared with the conventional spread ALOHA systems.
Sanada, Kosuke,Komuro, Nobuyoshi,Li, Zhetao,Pei, Tingrui,Choi, Young-June,Sekiya, Hiroo Elsevier 2018 AD HOC NETWORKS Vol.70 No.-
<P><B>Abstract</B></P> <P>It is an effective approach for comprehending network performance is to develop a mathematical model because complex relationship between system parameters and performance can be obtained explicitly. This paper presents generalized analytical expressions for end-to-end throughput of IEEE 802.11 string-topology multi-hop networks. For obtaining expressions, a relationship between the durations of the backoff-timer (BT) decrements and frame transmission is expressed by integrating modified Bianchi’s Markov-chain model and airtime expression. Additionally, the buffer queueing of each node is expressed by applying the queueing theory. The analytical expressions obtained in this paper provide end-to-end throughput for any hop number, any frame length, and any offered load, including most of analytical expressions presented in previous papers. The analytical results agree with simulation results quantitatively, which shows the verifications of the analytical expressions.</P>
Multiple-Packet Reception MAC Protocol Applying Pulse/Tone Exchange in MIMO Ad-Hoc Networks
Yoshida, Yuto,Komuro, Nobuyoshi,Ma, Jing,Sekiya, Hiroo Korea Multimedia Society 2016 The journal of multimedia information system Vol.3 No.4
This paper proposes a medium access control (MAC) protocol for multiple-input multiple-output (MIMO) ad-hoc networks. Multiple-packet receptions in MIMO systems have attracted as a key technique to achieve a high transmission rate. In the conventional protocols for multiple-packet receptions, timing offsets among multiple-frame transmissions cause frame collisions induced by hidden nodes, which degrades network performance. In the proposed protocol, transmission synchronization among hidden nodes can be achieved by applying pulse/tone exchanges. By applying the pulse/tone exchanges, multiple-packet receptions among hidden nodes can be achieved, which enhances network throughputs compared with the conventional protocol. Simulation results show effectiveness of the proposed protocol.
Indoor Human Positioning Tracking Technique to Support High-Quality Life
Toshinori Tsuboi,Takehiro Shiraishi,Nobuyoshi Komuro 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8
Information Communication Technology (ICT) is expected to assist the activities of senior persons for raising their quality of life. This paper proposes an indoor human position tracking technique using UHF-band RFID(radio frequency identification). Seniors are liable to forget where they put items, such as a wallet or watch in the house. They could find the lost item if they could recall their movement history. The proposed technique is well satisfies this goal. This paper proposes a new simple positioning technique based on RFID. Simulations and experiments are conducted to confirm the basic performance of the proposed positioning algorithm.