Fumikazu Ohkubo

Title: Fumikazu Ohkubo: Innovator in Voltage-Controlled Oscillator Technology

Introduction

Fumikazu Ohkubo is a notable inventor based in Kanagawa, Japan. He has made significant contributions to the field of electronics, particularly in the development of voltage-controlled oscillators. With a total of 2 patents to his name, Ohkubo's work has had a lasting impact on the industry.

Latest Patents

Ohkubo's latest patents include innovative designs for voltage-controlled oscillator systems. The first patent describes a voltage-controlled oscillator system that incorporates a ceramic resonator, a variable reactance circuit, and a limiter circuit. This system connects to the output of an amplifier, with feedback to the positive phase-sequence input. The frequency of oscillation is controlled by varying the equivalent capacitance of the reactance circuit using a control voltage. The limiter circuit enhances the variable frequency range on the high-frequency side and improves the symmetry of the capture range when applied to a phase-locked loop (PLL).

The second patent presents a voltage-controlled oscillator that is free from the need for free-run oscillating frequency adjustment. This design features an amplifier with a positive feedback loop, a resonator connected to the amplifier's output, and a variable reactance circuit. The reactance circuit allows for a variable reactance value controlled by a voltage, which in turn controls the oscillation frequency. Additionally, a low-pass filter is connected in cascade to the variable reactance circuit, and a high-pass filter is preferably included in the positive feedback loop.

Career Highlights

Throughout his career, Fumikazu Ohkubo has worked with prominent companies such as NEC Corporation and Pioneer Electronic Corporation. His experience in these organizations has contributed to his expertise in electronic innovations.

Collaborations

Ohkubo has collaborated with notable individuals in the field, including Naotoshi Higashiyama and Tetsuo Nakamura. These collaborations have further enriched his work and contributions to technology.

Conclusion

Fumikazu Ohkubo is a distinguished inventor whose work in voltage-controlled oscillators has advanced electronic technology. His patents reflect a deep understanding of complex electronic systems and their applications. His contributions continue to influence the industry and inspire future innovations.