Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Naoto Okumura is active.

Publication


Featured researches published by Naoto Okumura.


IEEE Journal of Solid-state Circuits | 2009

Heterogeneous Multicore SoC With SiP for Secure Multimedia Applications

Hiroyuki Kondo; Sugako Otani; Masami Nakajima; Osamu Yamamoto; Norio Masui; Naoto Okumura; Mamoru Sakugawa; Masaya Kitao; Koichi Ishimi; Masayuki Sato; Fumitaka Fukuzawa; Satoshi Imasu; Nobuhiro Kinoshita; Yusuke Ota; Kazutami Arimoto; Toru Shimizu

A heterogeneous multicore system-on-chip (SoC) has been developed for high-definition (HD) multimedia applications that require secure DRM (digital rights management). The SoC integrates three types of processors: two specific-purpose accelerators for cipher and high-resolution video decoding; one general-purpose accelerator (MX); and three CPUs. This is how our SoC achieves high performance and low power consumption with hardware customized for video processing applications that process a large amount of data. To achieve secure data control, hardware memory management and software system virtualization are adopted. The security of the system is the result of the cooperation between the hardware and software on the system. Furthermore, a highly tamper-resistant system is provided on our SiP (System in a package), through DDR2 SDRAMs and a flash memory that contain confidential information in one package. This secure multimedia processor provides a solution to protect contents and to safely deliver secure sensitive information when processing billing transactions that involve digital content delivery. The SoC was implemented in a 90 nm generic CMOS technology.


symposium on vlsi circuits | 2007

Design of a Multi-Core SoC with Configurable Heterogeneous 9 CPUs and 2 Matrix Processors

Masami Nakajima; Hiroyuki Kondo; Naoto Okumura; Norio Masui; Yukari Takata; Takashi Nasu; Hirokazu Takata; Takashi Higuchi; Mamoru Sakugawa; Hirokazu Yoneda; Hayato Fujiwara; Kazuya Ishida; Koichi Ishimi; Satoshi Kaneko; Teruyuki Itoh; Masayuki Sato; Osamu Yamamoto; Kazutami Arimoto

A multi-core SoC for multi-application (recognition, inference, measurement, control, and security) is developed. The configurable heterogeneous architecture with 9 CPUs and 2 matrix processors reduced 45% power consumption. The performance-oriented multi-bank matrix processor with 2-read-1-write calculation and background I/O operation is adopted. The 1 GHz CPU is realized by the delay management network applied for any kinds of applications and process technologies.


custom integrated circuits conference | 2008

Heterogeneous multicore SoC for secure multimedia applications

Hiroyuki Kondo; Masami Nakajima; Sugako Otani; Osamu Yamamoto; Norio Masui; Naoto Okumura; Mamoru Sakugawa; Masaya Kitao; Koichi Ishimi; Masayuki Sato; Fumitaka Fukuzawa; Kazuhiro Inaoka; Yoshihiro Saito; Kazutami Arimoto; Toru Shimizu

A heterogeneous multicore SoC (System on a Chip) has been developed for HD (high-definition) multimedia applications that require secure DRM (digital rights management). The SoC integrates three types of processors: two specific-purpose accelerators for a cipher and a high-resolution video decoding; one general-purpose accelerator (MX: Matrix processor); and three CPUs. This is how our SoC achieves high performance and low power consumption with hardware customized for video processing applications that process a large amount of data. To achieve secure data control, hardware memory management and software system virtualization are adopted. The security of the system is the result of the cooperation between the hardware and software on the system. Furthermore, a highly tamper-resistant system is provided on our SiP (system in a package), through DDR memories and Flash ROM that contain confidential information in one package. This secure multimedia processor provides a solution to protect contents and to safely deliver secure sensitive information when processing billing transactions that involve digital content delivery. The SoC was implemented in the 90 nm generic CMOS technology.


Archive | 2003

Cache system and cache memory control device controlling cache memory having two access modes

Teruyuki Itoh; Naoto Okumura


Archive | 1997

Microprocessor having a CPU and at least two memory cell arrays on the same semiconductor chip, including a shared sense amplifier

Takashi Higuchi; Naoto Okumura; Hideo Tsubota


Technical report of IEICE. ICD | 2008

Design and Evaluation of a Heterogeneous Multicore SoC with 9 CPUs and 2 Matrix Processors

Masami Nakajima; Koichi Ishimi; Naoto Okumura; Norio Masui; Osamu Yamamoto; Hiroyuki Kondo


Archive | 1996

Microcomputer with memory and processor provided on the same chip

Jun Ohtani; Naoto Okumura; Akira Yamazaki


symposium on vlsi circuits | 2008

Design and Implementation of a Configurable Heterogeneous Multicore SoC With Nine CPUs and Two Matrix Processors

Hiroyuki Kondo; Masami Nakajima; Norio Masui; Sugako Otani; Naoto Okumura; Yukari Takata; Takashi Nasu; Hirokazu Takata; Takashi Higuchi; Mamoru Sakugawa; Hayato Fujiwara; Kazuya Ishida; Koichi Ishimi; Satoshi Kaneko; Teruyuki Itoh; Masayuki Sato; Osamu Yamamoto; Kazutami Arimoto


Technical report of IEICE. SDM | 2007

Development of a Multi-Core SoC with 9 CPUs and 2 Matrix Processors

Masami Nakajima; Koichi Ishimi; Hayato Fujiwara; Kazuya Ishida; Naoto Okumura; Norio Masui; Hiroyuki Kondo


Archive | 2000

Microcomputer having memory and processor formed on the same chip

Ohtani Jun; Naoto Okumura; Akira Yamazaki

Collaboration


Dive into the Naoto Okumura's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge