| 摘要 |
PURPOSE: To provide a repeater appropriate for indoor high speed radio data transmission by providing an antenna for a passive type repeater with specific directivity. CONSTITUTION: A high gain antenna 3 for a repeater 4 is used for communication with a base station 1 provided with a high gain antenna 2. Since sharp directivity is provided between the station 1 and the repeater 4, a spatial, transmission loss can be reduced and communication up to a furthermore remote distance can be attained as compared with a case omitting the repeater 4. Since the repeater 4 and the station 1 are fixed, it is unnecessary to charge the direction of the antennas 3, 2. On the other hand, a low gain antenna 6 for the repeater 4 is used for communication with radio terminals 8a to 8c provided with low gain or high gain antennas 9a to 9c. Since directivity between the repeater 4 and the terminals 8a to 8c is not sharp and their spatial transmission losses are large, it is necessary to set the repeater 4 near the terminals 8a to 8c as close as possible. However since the directivity of the repeater side antenna 6 is moderate, it is unnecessary to make the terminals 8a to 8c opposed to each other, and even if terminals 8a to 8c are moved in some extent, communication can be executed without generating any trouble. |
