Takahiro Chihara

Title: Takahiro Chihara: Innovator in Frequency Control Circuits

Introduction

Takahiro Chihara is a notable inventor based in Nara, Japan. He has made significant contributions to the field of electronic engineering, particularly in the development of frequency control circuits. With a total of 2 patents to his name, Chihara's work has had a substantial impact on the technology used in communication systems.

Latest Patents

Chihara's latest patents include an Automatic Frequency Control (AFC) circuit and an MSK demodulator using one synchronous detector. The AFC circuit stabilizes the frequency of an intermediate frequency signal applied to a demodulation circuit. It utilizes a frequency conversion circuit that responds to a local oscillation signal generated from a voltage-controlled oscillation circuit. This innovation allows for the conversion of a digital modulation signal's frequency, which is then applied to the demodulation circuit. The carrier reproduction circuit within the demodulation circuit reproduces the carrier of the intermediate frequency signal, outputting a synchronizing detection signal. The frequency of the reproduced carrier is frequency-divided by a frequency dividing circuit, and the output is counted by a counter for a specific period. Data is then outputted from a microprocessor in response to the count output and the synchronizing detection signal, ultimately converting into an AFC voltage by a D/A converter. This process ensures a stable intermediate frequency signal through frequency division and counting.

The MSK demodulator includes a carrier reproducing circuit that synchronizes with the mark and space frequencies of an MSK signal. It features a detector for synchronous detection of the MSK signal using the reproduced carrier. Additionally, an identification circuit converts the analog output from the detector into serial digital data, which is then transformed into I, Q parallel data by a serial-parallel conversion circuit.

Career Highlights

Takahiro Chihara is currently employed at Sharp Kabushiki Kaisha Corporation, where he continues to innovate in the field of electronic circuits. His work has been instrumental in advancing technologies that enhance communication systems.

Collaborations

Chihara has collaborated with notable colleagues such as Masao Miyazaki and Tomozo Ohta, contributing to various projects that push the boundaries of electronic engineering.

Conclusion

Takahiro Chihara's contributions to frequency control circuits exemplify his