| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a portable machine suitably communicable with a communication object. <P>SOLUTION: This portable machine 3 has a first transmitting antenna 32 and a second transmitting antenna 33 transmittable to different transmission areas. Among the first transmitting antenna 32 and the second transmitting antenna 33, a transmitting antenna to transmit a response signal is selected by a changeover switch 31. That is, a transmission area of the response signal is selected by the changeover switch 31. Thus, when an operation control device 10 cannot receive its response signal when transmitting the response signal to the first area from the first transmitting antenna, the response signal is transmitted again by switching the transmitting antenna to the second transmitting antenna 33 from the first transmitting antenna 32. Thus, the response signal can be surely received to a car outside receiving antenna 13a. That is, the transmission area untransmittable in the first area of the first transmitting antenna 32 can be compensated by the second area of the second transmitting antenna 33. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
