Jun'ichi Nakagawa

Title: Jun'ichi Nakagawa: Innovator in Radio Technology

Introduction

Jun'ichi Nakagawa is a notable inventor based in Tokorozawa, Japan. He has made significant contributions to the field of radio technology, holding a total of 5 patents. His work has focused on enhancing the performance and reliability of radio receivers and frequency synthesizers.

Latest Patents

One of Nakagawa's latest patents is a radio receiver with an amplitude limiter prior to the mixer and band limiting. This invention discloses a radio receiver that amplifies an arbitrary receive signal through an input amplifier. The amplified signal is then converted into a predetermined frequency by a mixer. Following this, the signal is shaped in waveform by a band-limiting filter and further amplified and amplitude-limited by a limiting amplifier. To prevent distortion in the mixer circuit due to excessive input, an additional amplitude-limiting circuit is arranged before the mixer circuit.

Another significant patent is a frequency synthesizer that includes a voltage-controlled oscillator. This synthesizer outputs a value corresponding to a differential phase of a reference signal at a predetermined frequency. It samples the oscillating signal corresponding to the output of the voltage-controlled oscillator multiple times per period of a repeating frequency. The synthesizer generates phase information in a saw-tooth-like wave and calculates the difference between adjacent phase information. A comparator then calculates the difference between the first and second differential phases, leading to a signal processing unit that integrates the output and converts it to a voltage to control the voltage-controlled oscillator.

Career Highlights

Throughout his career, Jun'ichi Nakagawa has worked with prominent companies such as Hitachi, Ltd. and Hitachi Video Engineering, Incorporated. His experience in these organizations has allowed him to develop and refine his innovative ideas in radio technology.

Collaborations

Nakagawa has collaborated with notable coworkers, including Yoshitaka Takasaki and Kohei Ishizuka. Their combined expertise has contributed to the advancement of technology in their respective fields.

Conclusion

Jun'ichi Nakagawa's contributions to radio technology through his patents and collaborations highlight his role as an influential inventor. His work continues to impact the industry, showcasing the importance of innovation in technology.