About MATSUNAGA K
About Electronic Navigation Res. Inst., Tokyo, JPN
About HOSHINOO K
About Electronic Navigation Res. Inst., Tokyo, JPN
About IGARASHI K
About Communications Res. Lab., Tokyo, JPN
About Navigation (Manassas, Va.)
About Japan
About GPS
About Electronic navigation in general
About 日本
About GPS
About 電離層シンチレーション
About 観測