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We successfully produced Resistive-Electrode GEM (RE-GEM) that was applied Resistive-Kapton to electrodes. We measured the gain curve of RE-GEM using an 55Fe radioactive source in the gas mixture of Ar 70 % and CO 2 30 %. We obtained the maximum gain of about 300 at an applied voltage of 740 V.

The Gas Electron Multiplier (GEM) is a new device that amplifies an input electron cloud, while keeping its shape unchanged [1]. We have developed various type GEMs using a laser etching technique. Those GEMs had different geometry (pitch, hole diameter and thickness) and materials (polyimide; PI or liquid crystal polymer; LCP). We have applied the GEMs to a photoelectric polarimeter that measures polarization of X-rays emitted from stellar objects. To obtain the polarization accurately, it is necessary for GEMs to have good uniformity in two-dimension. As a result of gain mapping, the standard deviation of gain variation of our standard GEM was ∼ 5%. Our GEMs showed enough uniformity to detect X-ray polarization. Comparing hole diameter and gain maps of the same region, there was no correlation between these two maps. Comparing maps of different type GEMs, there was no difference among them and PI GEMs were more uniform than LCP ones.

A gas electron multiplier (GEM) is a key device for the photoelectric X-ray polarimeters, which will be launched in the near future. Our GEMs have spatial resolution enough for tracking of photoelectrons and low risk of discharge. GEMs need to perform well in all sorts of tolerance tests for space missions before launch. As a result of gain stability test after switching ON/OFF 6500 times repeatedly, our GEM gain variation is within ±2%. This repetition time scale corresponds to 2-year space mission in the Low Earth Orbit. As a result of charged particle (Fe) irradiation to GEM, our GEM survived more than 500 seconds of Fe ion irradiation (flux is 130 cts/cm2/s). This corresponds to 40-year irradiation in space. Thus, we conclude that our GEMs are stable enough for space missions and tolerance against discharge which is caused by charged particles.

Cm-level high accuracy real-time GPS positioning system is realized nation wide in Japan based on networked Real Time Kinematics GPS (RTK-GPS), and has been commercially operated by Mitsubishi Electric Co. named PAStrade, Positioning Augmentation Services, since September 2003. Also we have recently devised more convenient method at submeter or decimeter accuracy using low cost and compact code-ranging GPS receiver utilizing correction data fed from PAS system. Both of these methods will reduce time and cost significantly to produce precise satellite imagery based on Ground Control Point (GCP), as well as to update maps in geo-centric coordinate, which is necessary to use satellite imagery operationally with GPS

The premises cordless telephone (PCT) system provides a full function access to PSTN (public switched telephone network) subscriber lines via an existing PBX (private branch exchange) and/or a single controller or a network of controllers. The system enhances corporate communications by giving callers direct dial-through access to executives on the move and engineers and technicians working out of reach of wired telephones. The system offers similar benefits for offices, hotels, hospitals, building maintenance services, department stores, shopping malls, trade fairs, etc. Base stations configure the microcell structures with location registration and handoff features which will enable system planners to tailor the system economically to the diverse needs of traffic density and to eliminate the shadowing effects of building structures, walls, etc. The system features are described, including uses of the dynamic frequency assignment and flexible base station arrangement (irregularly located) within a microcell (or picocell) structure to ensure user-friendly operations, full extension of system flexibility, and significant increase in the traffic capacity within a highly dense traffic area. >