Location History:
- Suita, JP (2005 - 2008)
- Osaka, JP (1996 - 2014)
Company Filing History:
6 out of 16,453 
6 out of 27,375 
Years Active: 1996-2014
Title: Haruhiko Koizumi: Innovator in High Frequency Technology
Introduction
Haruhiko Koizumi is a prominent inventor based in Osaka, Japan. He has made significant contributions to the field of high frequency technology, holding a total of 12 patents. His work has been instrumental in advancing the capabilities of power amplifiers and wireless communication systems.
Latest Patents
One of Koizumi's latest patents is a high frequency power amplifier. This invention provides a compact design with a high degree of freedom regarding gain fluctuations immediately after the amplifier starts up. The amplifier includes a speed-up circuit that transiently increases a reference voltage during the rise of a control voltage, enhancing the bias supplied to an amplification transistor. The speed-up circuit consists of a capacitor and an overshoot control circuit, which determines the increasing amount of the reference voltage based on the charge amount in the capacitor.
Another notable patent is a detector circuit and system for wireless communication. This circuit features a simple configuration that accurately indicates power according to load fluctuations of a radio frequency power amplifier. It can be easily integrated into the radio frequency power amplifier. The detector circuit includes a detecting resistor for measuring a portion of the current flowing from a bias circuit and a current-voltage conversion circuit that transforms the detected current into a voltage. This allows the output current from the amplifying transistor to fluctuate in response to load changes, ensuring that the detection voltage follows these fluctuations.
Career Highlights
Throughout his career, Haruhiko Koizumi has worked with notable companies such as Panasonic Corporation and Matsushita Electric Industrial Co., Ltd. His experience in these organizations has contributed to his expertise in high frequency technology and innovation.
Collaborations
Koizumi has collaborated with talented individuals in his field, including Kazuki Tateoka and Masahiko Inamori. These collaborations have further enriched his work and led to advancements in technology.
Conclusion
Haruhiko Koizumi's contributions to high frequency technology and wireless communication systems have made a lasting impact in the industry. His innovative patents and collaborations highlight his role as a leading inventor in this field.