| 摘要 |
Procedure has the following steps: reception of data, transmitted from an emitter (4, 5) placed at an entrance, by an electronic card (16) carried by a person (8) or object; placing of the card in a second mode in which data is transmitted from the card, at a different frequency to the received frequency, to a receiver (12, 13) placed within the defined space that the person has entered. Independent claims are made for a system and an electronic unit for detection of individuals or objects within a defined space. The card is in a quasi-permanent receive mode so that it receives a signal at all times from the emitters and transmits a response either initially and or periodically. |
