| 摘要 |
An RF(Radio Frequency) indication terminal having plural loop antennas is provided to prevent a blind zone from being formed, to increase a recognition distance of a non-contact type card, and to solve an inconvenience of repeating card approaching operations caused by a communication error by regulating the strength of a magnetic field. An RF indication terminal includes an antenna unit(10), an impedance matching unit(30) and a card reader(40). The antenna unit includes the first antenna(11) and the second antenna(12). The first antenna is formed along an outer circumference of the antenna unit like a conventional single loop antenna. The number of turns on the antenna coil depends on a required strength of the magnetic field. The second antenna's position is determined according to an experiment value which makes the antenna unit maintain the strength of the magnetic field in accordance with an international standard. The impedance matching unit matches the impedance of the first antenna and the second antenna which receive signals from a traffic card. The card reader recognizes the traffic card by using the received signals. |
