インパルスラジオおよび直接拡散SS方式のUWB波源の試作(UWBシステム/一般)  [in Japanese] Development of Two Ultra Wideband Sources : Impulse Radio and Direct-Sequence Spread Spectrum  [in Japanese]

2002年2月に,Federal Communications Commission (FCC)は米国におけるUWBワイヤレスシステムの免許不要での個人的使用を暫定的に許可した.Ultra wideband (UWB)技術は超高速通信や高精度測位に活用できるとともに,実質的に新たなスペクトル資源を開拓するものとして期待されている.しかし,UWBシステムとスペクトルを共有する既存のワイヤレスシステムへの干渉や,UWBシステムの伝搬特性は十分に検討されているとは言い難い.ところが干渉や伝搬の実験にしようできるUWB波源は簡単には入手し難い.そこで,本報告ではUWB波源としてImpulse Radio波源および直接拡散(DS) UWB波源を試作し,その二種類の波源の特性を評価し特性の違いを示した.

In February 2002, the Federal Communications Commission (FCC) conditionally waived unlicensed operation of unlicensed of personal ultra wideband (UWB) products in the United States. The UWB technologies have been exploited to be able to use for super-high-speed communication, highly-accurate sensing and geolocation, low-cost RF tagging, and so forth ; and to pioneer a new spectrum resource substantially. Research areas, however, remain to be fully studied such as UWB propagation characteristics and interference effects from the UWB wireless systems to conventional narrow-band ones sharing the same frequency bands. No netheless, UWB sources have not been readily available for the experimented studies. This paper reports prototypes of impulse radio and direct sequence spread spectrum (DS-SS) UWB sources to serve for propagation, electromagnetic compatibility and other experimental studies.