Faculty Profiles - MATSUMOTO Takahiro

Papers - MATSUMOTO Takahiro

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Takahiro Matsumoto, Shinya Matsufuji . Construction of Optical ZCZ Code Generators With the Smallest Zero Correlation Zone . Proc. of the 10th International Conference on Applied Informatics and Communications (AIC'10) 216 - + 2010.8Construction of Optical ZCZ Code Generators With the Smallest Zero Correlation ZoneReviewed

Language：English Publishing type：Research paper (international conference proceedings) Publisher：WORLD SCIENTIFIC AND ENGINEERING ACAD AND SOC

In this paper, we propose the construction of two code generators for an optical ZCZ code of length N = 2(n), family size M = N/2-2 and zero correlation zone 1, which are called ROM-type and non ROM-type code generators. The optical ZCZ code is a set of pairs of binary and bi-phase sequences with zero correlation zone. An optical code division multiple access (CDMA) system using this code can remove co-channel interference and influence of multi-path. This ROM-type code generator can be constructed by a ROM and an up-counter. Similarly, this non ROM-type code generator can be constructed by an up-counter and logic gates. The ROM-type and non ROM-type code generators are implemented on a field programmable gate array (FPGA) corresponding to 400,000 logic gates, and the non ROM-type code generator can reduce logic elements than the ROM-type code generator.

Shinya Matsufuji, Takahiro Matsumoto . On Logic Functions of Complementary Arrays of Length 2(n) . Proc. of the 10th International Conference on Applied Informatics and Communications (AIC'10) 208 - + 2010.8On Logic Functions of Complementary Arrays of Length 2(n)Reviewed

Publisher：WORLD SCIENTIFIC AND ENGINEERING ACAD AND SOC

Complementary arrays means genaralization of a pair of sequences to multi-dimension, that at the same phase-shift the sum of these aperiodic auto-correlation functions takes zero except zero-shift. This paper considers logic functions of complementary arrays with length 2(n) including polyphase arrays whose elements consist of unit magnitude. The functions can show that these number is huge and relates to the phase number and length, but not dimension.

Takahiro MATSUMOTO, Shinya MATSUFUJI . Compact Bank of Matched Filters for Optical ZCZ Codes Using Fast Algorithm for M-sequence Type Hadamard Matrix . Proc. of the 2010 RISP International Workshop on Nonlinear Circuits, Communications and Signal Processing (NCSP'10) 628 - 631 2010.3Compact Bank of Matched Filters for Optical ZCZ Codes Using Fast Algorithm for M-sequence Type Hadamard MatrixReviewed

Takahiro Matsumoto, Shinya Matsufuji . BER Performance of M-ary/ASK-SS System Using Compact Matched Filter Bank for Optical ZCZ Code . Proc. of the 12th International Conference on Advanced Communication Technology (ICACT2010) 617 - 622 2010.2BER Performance of M-ary/ASK-SS System Using Compact Matched Filter Bank for Optical ZCZ CodeReviewed

Publisher：IEEE

The optical ZCZ code, which is a set of pairs of binary and bi-phase sequences with zero correlation zone, can provide code division multiple access (CDMA) communication system without co-channel interference. And M-ary amplitude shift keying spread spectrum (M-ary/ASK-SS) system using this code can detect a desired sequence without interference of undesired sequences. We proposed the compact construction of a bank of matched filters for this code, which is called tree-type bank of matched filters. However, M-ary/ASK-SS system using this filters might go down the bit error rate (BER) performance because input-output characteristics of this filters for zero correlation zone 4n-2 is nonlinear characteristics.
In this paper, we clarify that BER performance in ASK-SS and M-ary/ASK-SS system under the additive white Gaussian noise (AWGN) and the frequency nonselective fading environments are not influenced by nonlinear characteristics of this filters by the computer simulation. The BER performance of ASK-SS system using tree-type bank of matched filters under the AWGN and frequency nonselective fading environments go down compared to BER performance of parallel-type filters as expected. But the BER performance of M-ary/ASK-SS system using this compact filters under the AWGN and frequency nonselective fading environment are almost equal compared to BER performance of parallel-type filters. In fact, the BER performance in M-ary/ASK-SS are not influenced by nonlinear characteristics of tree-type bank of matched filters.

Takahiro Matsumoto, Yu Suwaki, Shinya Matsufuji . Indoor Experiment of BER Performance of Optical CDMA System Using Optical ZCZ Code . Proc. of the 12th International Conference on Advanced Communication Technology (ICACT2010) 890 - 893 2010.2Indoor Experiment of BER Performance of Optical CDMA System Using Optical ZCZ CodeReviewed

Publisher：IEEE

The optical ZCZ code, which is a set of pairs of binary and bi-phase sequences with zero correlation zone, can provide optical code division multiple access (COMA) communication system without co-channel interference. We proposed the compact construction of a code generator and a bank of matched filters for this code.
In this paper, we verified that this system can suppress co-channel interference and interference by shifting of optical axis by data multiplex transmission experiment of optical COMA system using optical ZCZ codes which is called ZCZ-COMA system, consisting of a infrared light emitting diode(LEO), an avalanche photo diode(APO) module and field programmable gate array(FPGA) boards corresponding to 400,000 logic gates.
As a result of data transmission experiment, optical ZCZCOMA system can suppress co-channel interference, but can't remove completely co-channel interference, and interference by shifting of optical axis is suppressed from about -30 to 30 degrees.

Jincheng Huang, Shinya Matsufuji, Takahiro Matsumoto, Noriyoshi Kuroyanagi . A Study on ZCZ-CDMA Systems in Short-Range Wireless Communications . Proc. of the Ninth IEEE Malaysia International Conference on Communications (MICC 2009) 565 - 569 2009.12A Study on ZCZ-CDMA Systems in Short-Range Wireless CommunicationsReviewed

Publisher：IEEE

ZCZ-CDMA systems, which can remove co-channel interference by means of synchronization control and use of ZCZ codes, are useful for Short-Range Wireless communications. This paper investigates BER performance on ZCZ-CDMA systems using ASK, PSK, and BFSK modulations. This paper proposes a ZCZ-CDMA demodulation using signals which result from the combination of the preceding signal and the delayed signal. Because the preceding signal and delayed signal contain the same information, the path diversity gain is obtained by combining them. Computer simulations confirm that the BER performance is improved by combining the desired signals over Multipath fading channels.

DOI： 10.1109/MICC.2009.5431434

DOI： 10.1109/MICC.2009.5431434

Takayuki Hirano, Shinya Matsufuji, Takahiro Matsumoto, Koichi Takimoto, Fusanori Miura . On Lattice Wireless Network for Autonomous Distributed System . Proc. of the Ninth IEEE Malaysia International Conference on Communications (MICC 2009) 725 - 729 2009.12On Lattice Wireless Network for Autonomous Distributed SystemReviewed

Publisher：IEEE

A lattice wireless network consisting of plural units, which possess sensor devices, communication devices, control devices, and processors, will be flexibly adapted for autonomous distributed sensor network systems.
This paper clarifies the transmission characteristics of lattice wireless networks when a lot of communications happen at the same time between plural units and gives an approximation of data transmission time.

DOI： 10.1109/MICC.2009.5431402

DOI： 10.1109/MICC.2009.5431402

Takahiro Matsumoto, Yu Suwaki, Shinya Matsufuji . Experimental Evaluation of Parallel Transmission Using Optical ZCZ-CDMA System . Proc. of the Fourth International Workshop on Signal Design and Its Applications in Communications (IWSDA'09) 118 - 121 2009.10Experimental Evaluation of Parallel Transmission Using Optical ZCZ-CDMA SystemReviewed

Publisher：IEEE

In the high speed parallel transmission of optical wireless communication, shifting of optical axis is important problem. An optical CDMA system using the optical ZCZ code is proposed as a method with the possibility that this problem can be solved without complicating hardware. The optical ZCZ code, which is a set of pairs of binary and bi-phase sequences with zero correlation zone, can provide optical code division multiple access (CDMA) communication system without co-channel interference. We proposed the compact construction of a code generator and a bank of matched filters for this code.
In this paper, we verified that this system can remove co-channel interference even if an optical axis is shifted, by experiment of parallel transmission using an optical ZCZ-CDMA wireless communication system, consisting of a infrared light emitting diode(LED), an avalanche photo diode(APD) module and field programmable gate array(FPGA) boards corresponding to 400, 000 logic gates. Desired to undesired signal ratio (DU ratio) in correlation output whose shiftings of optical axis are 0 degrees and 45 degrees are improved about 61.9dB and 39.1dB, respectively. As a result of experiment on the optical parallel transmission, it was proved that this system was able to suppress interference by shifting of optical axis.

DOI： 10.1109/IWSDA.2009.5346407

DOI： 10.1109/IWSDA.2009.5346407

Takayuki Hirano, Shinya Matsufuji, Takahiro Matsumoto, Koichi Takimoto, Fusanori Miura . On Transmission Characteristics of Lattice Wireless Networks . Proc. of the Fourth International Workshop on Signal Design and Its Applications in Communications (IWSDA'09) 177 - 180 2009.10On Transmission Characteristics of Lattice Wireless NetworksReviewed

Publisher：IEEE

A lattice wireless network consisting of plural units, which possess sensor devices, communication devices, control devices, and processors, will be flexibly adapted for autonomous distributed sensor network systems. This paper clarifies its transmission characteristics for lattice shape and the number of units transmitting data, simultaneously.

DOI： 10.1109/IWSDA.2009.5346424

DOI： 10.1109/IWSDA.2009.5346424

Jincheng Huang, Shinya Matsufuji, Takahiro Matsumoto, Noriyoshi Kuroyanagi, Pingzhi Fan . On BFSK-ZCZ-CDMA Systems . Proc. of the Fourth International Workshop on Signal Design and Its Applications in Communications (IWSDA'09) 32 - + 2009.10On BFSK-ZCZ-CDMA SystemsReviewed

Publisher：IEEE

Quasi-synchronous CDMA systems, which can remove co-channel interference by means of synchronization control and use of a ZCZ code, are useful for Short-Range Wireless communications. This paper proposes a BFSK-ZCZ-CDMA modulation system which appears more advantageous in bit-error-rate performance over multi-path fading channels than ASK or PSK modulation scheme. In this system, a balanced ZCZ code and a quasi-coherent detection with IQ separation are used. The bit-error-rate performances over AWGN and fading channels are simulated.

DOI： 10.1109/IWSDA.2009.5346430

DOI： 10.1109/IWSDA.2009.5346430

Shinya Matsufuji, Takahiro Matsumoto, Tomohiro Hayashida, Takafumi Hayshi, Noriyoshi Kuroyanagi, Pingzhi Fan . On a ZCZ Code Including a Sequence Useful for Synchronization . Proc. of the Fourth International Workshop on Signal Design and Its Applications in Communications(IWSDA'09) 28 - + 2009.10On a ZCZ Code Including a Sequence Useful for SynchronizationReviewed

Takahiro Matsumoto, Shinya Matsufuji . Matched Filter Implementation on FPGA for Integrand Code Using a Real-Valued Shift-Orthogonal Finite-Length Sequence . Proc. of the 11th International Conference on Advanced Communication Technology (ICACT2009) 179 - 183 2009.2Matched Filter Implementation on FPGA for Integrand Code Using a Real-Valued Shift-Orthogonal Finite-Length SequenceReviewed

Publisher：ELECTRONICS TELECOMMUNICATIONS RESEARCH INST

In this paper, we proposed the compact construction of a matched filter for integrand code, which do not require the high-rate clock pulse in two-valued PWM (pulse width modulation) code, using a real-valued shift-orthogonal finite-length sequence, which has a sharp aperiodic autocorrelation function with zero sidelobes except at left and right shift-ends. This matched filters is implemented on a field programmable gate array (FPGA) corresponding to 400, 000 gates. A proposed matched filter for the sequence of length 129 can be constructed by the circuit scale of about 47% compared with conventional filter.

Yu SUWAKI, Takahiro MATSUMOTO, Shinya MATSUFUJI . Experimental Evaluation of Optical ZCZ-CDMA System . Proc. of the 23rd International Technical Conference on Circuits/Systems, Computers and Communications (ITC-CSCC2008) 1809 - 1812 2008.7Experimental Evaluation of Optical ZCZ-CDMA SystemReviewed

Yukari TSUCHIYAMA, Shinya MATSUFUJI, Takahiro MATSUMOTO . Generalization of Even-Shift Orthogonal Sequences to Multi-Dimension . Proc. of the 23rd International Technical Conference on Circuits/Systems, Computers and Communications (ITC-CSCC2008) 1425 - 1428 2008.7Generalization of Even-Shift Orthogonal Sequences to Multi-DimensionReviewed

Takahiro Matsumoto, Yoshihiro Tanada . A Real-Valued Periodic Orthogonal Sequence Derived from A Real-Valued Shift-Orthogonal Finite-Length Sequence and Its Fast Periodic Correlation Algorithm . Electronics and Communications in Japan，Part 390 ( 10 ) 18 - 28 2007.10A Real-Valued Periodic Orthogonal Sequence Derived from A Real-Valued Shift-Orthogonal Finite-Length Sequence and Its Fast Periodic Correlation AlgorithmReviewed

Publisher：SCRIPTA TECHNICA-JOHN WILEY & SONS

This paper proposes a real-valued orthogonal periodic sequence of a period N = 2(nu) derived from a real-valued shift-orthogonal finite-length sequence of length M = 2(nu) + 1. This paper also explains the principle of a fast correlation algorithm that efficiently executes periodic correlation processing for this real-valued orthogonal periodic sequence. The sidelobe of an aperiodic autocorrelation function for a real-valued shift-orthogonal finite-length sequence (length of M) is 0 except for the right and left ends of the shift. If the subsequent sequence of first values repeatedly overlap the final values of this sequence, a real-valued orthogonal periodic sequence of a period N = M - 1 can be obtained. A real-valued orthogonal periodic sequence of a period N = 2(nu) generated from real-valued shift-orthogonal finite-length sequence of length M = 2(nu) + I is obtained by convoluting partial sequences and based on that controls the number of multiplications and the number of additions to increment on the order of Nlog(2)N without using fast Fourier trans formation. (C) 2007 Wiley Periodicals, Inc.

DOI： 10.1002/ecjc.20294

DOI： 10.1002/ecjc.20294

Takahiro Matsumoto, Shinya Matsufuji . Code generator implementation on FPGA for an optical ZCZ code using a Sylvester type Hadamard matrix . Proc. of 2007 International Workshop on Signal Design and Its Applications in Communications (IWSDA'07) 228 - 232 2007.9Code generator implementation on FPGA for an optical ZCZ code using a Sylvester type Hadamard matrixReviewed

Publisher：IEEE

The optical ZCZ code is a set of pairs of binary and bi-phase sequences with zero correlation zone. An optical code division multiple access (CDMA) system using this code can remove co-channel interference and influence of multi-path. We proposed the compact construction of a bank of matched filters for this code in a receiver. But we have not proposed the construction of a code generator for this code in a transmitter yet.
In this paper, we propose the construction of two code generators for an optical ZCZ code using a Sylvester-type Hadamard matrix, which are called ROM-type and non ROM-type code generators. This ROM-type code generator can be constructed by a ROM and a up-counter. Similarly, this non ROM-type code generator can be constructed by a up-counter, flip-flops and logic gates. The ROM-type and non ROM-type code generators are implemented on a field programmable gate array (FPGA) corresponding to 400, 000 logic gates, and the non ROM-type code generator can reduce logic elements than the ROM-type code generator.

DOI： 10.1109/IWSDA.2007.4408365

DOI： 10.1109/IWSDA.2007.4408365

Yoshihiro Tanada, Takahiro Matsumoto . Fast Aperiodic Correlation Algorithm for Real-Valued Shift-Orthogonal Finite-Length Sequence of Length 2^ν+1 . Electronics and Communications in Japan90 ( 9 ) 18 - 30 2007.9Fast Aperiodic Correlation Algorithm for Real-Valued Shift-Orthogonal Finite-Length Sequence of Length 2^ν+1Reviewed

Publisher：SCRIPTA TECHNICA-JOHN WILEY & SONS

Real-valued shift-orthogonal finite-length sequences are sequences in which the side lobes of the aperiodic autocorrelation function become 0, except for the end points of the shift to both sides, and can be applied in pulse compression radar and spread spectrum communications. In this paper, a fast correlation algorithm for efficiently calculating the periodic correlation function is discussed for real-valued shift-orthogonal finite-length sequences with length M = 2 nu + 1. For input data, including a real-valued shift-orthogonal finite-length sequence over a certain range, the value of the aperiodic correlation function is found in a certain shift range. Based on the synthesis of this sequence by the convolution of nu + I partial sequences, the correlation processing is broken down into correlation processing of the nu + I stages of partial sequences. As a result, the number of multiplications and the number of additions can be suppressed on the order M 1092 M. (C) 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(9): 18-30,2007; Published online in Wiley InterScience (www.interscience.wiley.com).

DOI： 10.1002/ecjc.20301

DOI： 10.1002/ecjc.20301

Shinya Matsufuji, Takahiro Matsumoto, Kouki Funakoshi . Properties of Even-Shift Orthogonal Sequences . Proc. of 2007 International Workshop on Signal Design and Its Applications in Communications (IWSDA'07) 181 - + 2007.9Properties of Even-Shift Orthogonal SequencesReviewed

Publisher：IEEE

This paper investigates properties of the even-shift orthogonal sequence of length 2(n), whose out-of-phase aperiodic auto-correlation function takes zero at any even shift. It is shown that the halves of all E-sequences with odd n produced by logic functions are balanced sequences, whose elements 1 and -1 appear half, and there is not any balanced E-sequence for even n. Furthermore it is also shown that the aperiodic auto-correlation function possesses low values at odd shifts.

DOI： 10.1109/IWSDA.2007.4408353

DOI： 10.1109/IWSDA.2007.4408353

Takahiro Matsumoto, Shigeo Tsukiashi, Shinya Matsufuji, Yoshihiro Tanada . The bank of matched filters for an optical ZCZ code using a sylvester type hadamard matrix . IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCESE89A ( 9 ) 2292 - 2298 2006.9The bank of matched filters for an optical ZCZ code using a sylvester type hadamard matrixReviewed

Publisher：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG

The optical ZCZ code is a set of pairs of binary and biphase sequences with zero correlation zone. An optical M-ary direct sequence spread spectrum (M-ary/DS-SS) system using this code can detect a desired sequence without interference of undesired sequences. However, the bank of matched filters in a receiver circuit may fall into large scale. In this paper, we propose the compact construction of a bank of matched filters for an M-ary/DS-SS system using an optical ZCZ code. This filter bank can decrease the number of 2-input adders from O(N-2) to O(N) and delay circuits from O(N-2) to O(N log(2) N), respectively, and is implemented on a field programmable gate array (FPGA) corresponding to 400, 000 logic gates.

DOI： 10.1093/ietfec/e89-a.9.2292

Shinya Matsufuji, Takahiro Matsumoto, Yoshihiro Tanada, Noriyoshi Kuroyanagi . ZCZ codes for ASK-CDMA system . IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCESE89A ( 9 ) 2268 - 2274 2006.9ZCZ codes for ASK-CDMA systemReviewed

Publisher：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG

This paper presents two kinds of new ZCZ codes consisting of trios of two binary sequences and a bi-phase sequence, which can reach the upper bound on the ZCZ codes. From the viewpoint of sequence design, it is shown that they can provide the most effective ASK-CDMA system, which can remove co-channel interference.

DOI： 10.1093/ietfec/e89-a.9.2268

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