| 摘要 |
When communicating with a traditional interrogator of passive smart tags, an actively transmitting smart tag of the invention, even within a data frame being transmitted, observes a first phase (Φi) being a phase of a voltage induced in a tag's antenna by an interrogator's high-frequency carrier signal and transmits wave packets in that it excites the antenna with a voltage having a phase (Φt), which is always set at the beginning of transmission of each said wave packet shifted with respect to said first phase (Φi) by the same phase angle (&Dgr;Φ). At &Dgr;Φ=180° an amplitude of voltage across an interrogator's antenna, when some of said wave packets influence this antenna, attains the largest attainable interference rise. Miniature actively transmitting smart tags are enabled to wirelessly communicate with said traditional interrogator and a communication range of pocket-sized tags is herewith increased.
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