| 摘要 |
PROBLEM TO BE SOLVED: To provide radio equipment having a high radiation characteristic and satisfactory communication performance in a communication state when the equipment is arranged in various places and used for crime prevention purpose. SOLUTION: The radio equipment is provided with an external antenna 2 installed outside a cabinet of radio equipment 1, an antenna 9 which is disposed inside the cabinet and whose main polarization component differs from that of the external antenna 2, an operation processing means 15 judging reception levels of the external antenna 2 and the antenna 9 and a high frequency switch 7 selecting the external antenna 2 or the antenna 9 in accordance with a judged result of the operation processing means 15. Thus, the high radio characteristic and satisfactory communication performance can be kept even under a condition that the polarization component in a hard multipath phasing environment such as out of visibility or in the house is not constant. COPYRIGHT: (C)2004,JPO
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