Inventor
KAWAKAMI HIROTO
JP20 patents
⚠️ This page may combine multiple inventors who share the name “KAWAKAMI HIROTO”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
NIPPON TELEGRAPH & TELEPHONE
15 patentsUS6263139B1Jul 17, 2001
Optical transmission system with group velocity dispersion compensation
NIPPON TELEGRAPH & TELEPHONE90 citations97
US11397363B2Jul 26, 2022
Automatic bias control circuit
NIPPON TELEGRAPH & TELEPHONE9 citations85
US11159242B2Oct 26, 2021
Optical transmitter
NIPPON TELEGRAPH & TELEPHONE9 citations85
US10090921B2Oct 2, 2018
Light modulation device and light modulation method
NIPPON TELEGRAPH & TELEPHONE7 citations81
US10823989B2Nov 3, 2020
Bias control circuit and bias control method
NIPPON TELEGRAPH & TELEPHONE4 citations72
US10536238B2Jan 14, 2020
Optical transmission system, optical transmission apparatus, and optical reception apparatus
NIPPON TELEGRAPH & TELEPHONE3 citations72
US10313015B2Jun 4, 2019
Optical transmitter and bias voltage control method
NIPPON TELEGRAPH & TELEPHONE6 citations72
US10243664B2Mar 26, 2019
Optical modulator driver circuit and optical transmitter
NIPPON TELEGRAPH & TELEPHONE5 citations71
US11711198B2Jul 25, 2023
Synchronous detection apparatus, synchronous detection method, and program
NIPPON TELEGRAPH & TELEPHONE0 citations62
US7379236B2May 27, 2008
Optical fiber communication system using remote pumping
NIPPON TELEGRAPH & TELEPHONE2 citations62
US12170542B2Dec 17, 2024
Optical transmitter
NIPPON TELEGRAPH & TELEPHONE0 citations52
US11194219B2Dec 7, 2021
Optical modulator
NIPPON TELEGRAPH & TELEPHONE0 citations52
US12372721B2Jul 29, 2025
Depolarizer and optical amplifier excitation apparatus
NIPPON TELEGRAPH & TELEPHONE0 citations51
US11822161B2Nov 21, 2023
Bias voltage adjustment apparatus and IQ optical modulation system
NIPPON TELEGRAPH & TELEPHONE0 citations51
US11646800B2May 9, 2023
Optical transmitter and method for controller optical transmitter
NIPPON TELEGRAPH & TELEPHONE0 citations51