| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a radio frequency identification system using a modulation backscatter with a single system, a single infrastructure, and a security, location determination and low-speed data communication application by providing such a system that solves respective problems of security, location determination, and a low-speed data communication application. SOLUTION: A radio communications system can operate in one of several modes which integrate in-building security, location determination, messaging, and data communications capabilities. The system has one or more interrogators for generating and transmitting a radio signal. One or more tags of the system receive the radio signal. A backscatter modulator modulates the reflection of the radio signal using subcarrier signal, thereby forming a reflected modulated signal. The interrogators receive and demodulate the reflected modulated signal. The system can also be used for other systems, such as electronic mail, voice mail, location determination and inventory management.</p> |
