| 摘要 |
PURPOSE:To use efficient radio frequency repeatedly without changing the radio frequency even if a mobile station shifts a zone during communication by assigning from the radio frequency being used in a distant radio zone free from interference to the mobile station intended to assign the radio frequency. CONSTITUTION:A first neighboring area is constituted of plural radio zones 202 to 207 directly neighboring to the radio zone 201 where the mobile station requesting the assignment of the radio frequency stands so as to surround it, and a second neighboring area is constituted of plural radio zones 205 to 219 directly neighboring to the first neighboring area so as to surround it, and a third neighboring area is constituted of plural radio zones 220 to 237 directly neighboring to the second neighboring area so as to surround it. The radio frequency not being used within the first, the second and the third neighboring areas is assigned, and when all the radio frequencies are being used within the third neighboring area, the radio frequency not being used within the second neighboring area is assigned, and when all the radio frequencies are being used within the second neighboring area, the radio frequency not being used within the first neighboring area is assigned. |
