Tomozo Ohta

Compact microwave remote recognition system with newly developed SSB modulation

A compact microwave remote recognition system (2.45 GHz) built with a new type of SSB (single-sideband) modulation is presented. The system is composed of an interrogator and a responder. The interrogator is able to read and write the data that are stored in the responder by remote control. The SSB modulation makes microwave circuits simpler. By using a microwave PLO, radio interference to neighboring systems is eliminated. This system is widely applicable to factory automation, personnel management, security management, etc. Key technologies to construct this system are described.<<ETX>>

Very Small and Light Ku-Band Low Noise Converter with Low Noise FET Mixer

The very small sized and light weighted satellite receiving converter with excellent characteristics has been developed for the Ku-band. The very low noise FET mixer is newly developed and used for the converter. Because of the realization of the low noise FET mixer, the excellent characteristics of the converter with two-stage low noise amplifier which is composed of the HEMT and the FET are obtained. In addition, the special strip-line corner is developed and applied in order to make the converter size smaller. The characteristics of the converter with these technologies are the noise figure of 1.7dB max, the conversion gain of 55dB min and the image rejection ratio of 50db min. Total power consumption of the converter is 1.7w. The converter are particulary very small volume of 100cc and light weight of 180g.

New Ku-Band Low Noise Converter Directly Coupled with Helical Antenna

This paper describes the constitution, characteristics, and technically unique key points on the design of the newly developed Ku-band converter. The converter is composed of a FET low noise amplifier directly coupled with a helical antenna and a new finline mixer.

10GHz Band Compact Phase Locked Oscillator with Low Phase Noise

The small-sized and light-weighted 10GHz band Phase Locked Oscillator(PLO) with superior characteristics, cost effectiveness and high productivity have been newly developed for satellite communication systems such as VSAT. The PLO is composed of three circuit modules, the small-sized 2.7GHz band VCO module, the x4 frequency multiple module and the PLL/Power suplly module. The output phase noise characteristics is evaluted in theoretically by simple noise model considering the phase noises generated in the divider, the phase-detector, the VCO and others. The measured phase noise of PLO is in good agreement with the calculated. The characteristics of the PLO are ¿75dBc/Hz at 100Hz, ¿84dBc/Hz at 10KHz in the phase noise and less than ±2ppm(¿40~+60°C) in the frequency stability. The volume is about 110cc and the weight is 185g.