For few years, we had been concentrated on a development of completely closed diamond synthesizing system aimed for microgravity or high gravity experiments. Recently we started the new methods with graphite heater as carbon source and tried to synthesize diamond via gaseous phase of vaporized acetone. With both methods, completely closed system is successfully performed. With liquid carbon source, such as acetone, impurity elements will be easily substituted in synthesized diamond thin film which has wide applications for the future electronic devices. In-situ gaseous species analyzed with gas chromatographic analysis and possible reaction model will be discussed.

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NASDA is developing a multiple channels and multi-functional GPS (Global Positioning System) receiver for space applications (Ref. 1). It has 48 or more channels and multi-antennas for attitude determination or dual frequencies processing. It also has rapid acquisition function using a matched filter technique in order to recover from momentary lock-loss. The development of the new GPS equipment provides an attractive navigation system for Launch Vehicle (LV). Depending on the number of GPS antenna, their configuration and the satellite geometry, the visibility of satellite and the navigation accuracy will vary. This paper presents the work to be done during the planning stage of setting up a GPS multi-antenna system is to properly select the antenna configuration to maximize the coverage of multi-antenna and the navigation performance. Visibility analysis has been performed oh two typical trajectories of LEO and GTO mission. Based on the results from this research, the multi-antenna system with five antennas is recommended for the LV applications. At least four satellites are in view at any times on the trajectories using the five antenna configuration. The simulation results show the average of GDOP (Geometrical Dilution Of Precision, which is geometric index of navigation accuracy) is below 5.0 during the angler velocity of 40 deg/s.

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We have studied specifications for satellite transponder to perform nationwide emergency medical network for ambulance over Japan. If it is possible to send in real-time a large volume of biological data (such as when a thrombolytic dose is administered to a patient suffering acute cardiac infarction being conveyed in an ambulance, based on his or her 12 leads electrocardiogram data and cardio-echogram with compressed motion picture, for early treatment for removal of a coronary occlusion) and color video images (such as light reflex images and video images of the airway) from an ambulance to a triage center to receive instructions from a doctor, more patients will be saved and medical expenditures for emergency medicine will ultimately be reduced. We investigate required specifications as follows; 1) Channels, 2) Bandwidth, 3) Frequency, 4)Footprints, 5) Technical limitations of the transponder others.

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Based on the assumption that technical problems and regulations will be eliminated by the use of the 3G wireless mobile phone in the future, we compared the 3G wireless mobile phone and the HEO satellite in terms of the cost for transmitting video data from ambulances at 2 Mbps, relying on available public data It was assumed that a dedicated line (2 Mbps for ambulance use only) would be added to the 3G wireless mobile phone service offered in Tokyo, Osaka, and Nagoya by NTT DoCoMo. The cost for adding such a dedicated line and transceivers at transit nodes in the 3G network was compared with that of Highly Inclined Elliptic Orbit (HEO) (four satellites)-based service. If the two methods are compared on a nationwide basis, the use of a 2 Mbps line dedicated to ambulance communications will be 15 times as costly per capita as the satellite-based service, and as much as 489 times costly per area.

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