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Koriyama, Japan

Hitachi Telecom Technologies, Ltd

USPTO Granted Patents = 61

% Expired Patents = 18.0

Forward Citations = 202

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71 inventors (with patents filed for the assignee):

Tatsuo Yamauchi (9 out of 9 patents)

Kimitoshi Takeuchi (8 out of 8 patents)

Kazumasa Azuma (6 out of 8 patents)

4. Sakae Watanabe (6 out of 6 patents)

5. Ikuo Aso (6 out of 6 patents)

6. Kazuo Sanpei (6 out of 6 patents)

7. Shinya Suzuki (5 out of 6 patents)

8. Toru Yoshihara (5 out of 6 patents)

9. Fumiyoshi Oono (5 out of 5 patents)

10. Tomonobu Watanabe (5 out of 5 patents)

11. Makoto Oohashi (4 out of 4 patents)

12. Toshie Takahashi (4 out of 4 patents)

13. Kaoru Suzuki (4 out of 4 patents)

14. Yoshihisa Domoto (4 out of 4 patents)

15. Junichi Tanji (4 out of 4 patents)

Core Competencies:

DTMF Transmission

Packet Data Processing

Communication Systems

ATM Equipment

Multiplexing

Line Switching

Speech Systems

Digital Telephone

Dealing Communication

ISDN Circuits

Remote Trading

Electric Appliances

61 patents: Sort by Forward Citations

1. 7532606 - DTMF signal transmission method and communication apparatus (2009-05-12),

2. 7120171 - Packet data processing apparatus and packet data processing method (2006-10-10),

3. 7103036 - Voice data relay apparatus (2006-09-05),

4. 7099456 - Call center system (2006-08-29),

5. 7062033 - DTMF signal transmission method and communication apparatus (2006-06-13),

6. 7058060 - ATM apparatus, IP apparatus and bus system (2006-06-06),

7. 7050570 - DTMF signal transmission method and communication apparatus (2006-05-23),

8. 7050438 - Cell creation method for control line signals of ATM Network and multiplexing equipment (2006-05-23),

9. 7035265 - Multiplexer and priority control method for packet data transmissions (2006-04-25),

10. 6970460 - Multiplexing apparatus (2005-11-29),

11. 6912220 - ATM equipment (2005-06-28),

12. 6898178 - ATM device, subscriber system, communication system and backup method (2005-05-24),

13. 6892232 - Local networking system for registering unregistered terminals (2005-05-10),

14. 6862290 - Line switching system and line switching unit of dynamic band variation unit (2005-03-01),

15. 6836545 - Communication system, exchange and communication holding control method (2004-12-28),

Company Overview

Hitachi Telecom Technologies, Ltd, based in Koriyama, Japan, specializes in advanced telecommunication systems. The company focuses on developing and manufacturing technologies related to DTMF transmission, packet data processing, and communication systems. Its expertise extends to ATM equipment, multiplexing, line switching, and speech systems, contributing significantly to the evolution of digital telephone technologies. Hitachi Telecom is committed to enhancing connectivity and communication efficiency across various platforms.

Profile summary synthesized from public USPTO records and patent filings.

Company Badge

USPTO Data Jan 1 1976 - Oct 13 2026

61 Patents

#1 in Koriyama

#1,512 in Japan

#11,923 in the World

Koriyama, Japan

Hitachi Telecom Technologies, Ltd

Forward Citations = 202

71 inventors:

Tatsuo Yamauchi (9 out of 9 patents)

Kimitoshi Takeuchi (8 out of 8 patents)

Kazumasa Azuma (6 out of 8 patents)

4. Sakae Watanabe (6 out of 6 patents)

5. Ikuo Aso (6 out of 6 patents)

IDiyas Innovation Intelligence. (2026). Company Patent Portfolio: Hitachi Telecom Technologies, Ltd. Retrieved from https://idiyas.com/company/hitachi-telecom-technologies

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

Data Sources: USPTO Patent Grant XML, Patent Center, EPO & CIPO • Normalized by IDiyas Innovation Graph. Methodology & provenance architecturePlease report any incorrect information to [email protected]

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