| 摘要 |
A mobile telephony system includes an internal part-system (6), which is installed in a building (1) and an external part-system (7). The internal part-system has internal base stations (BSI) which are connected to a mobile switching centre (MSC), to which external base stations (BS1, BS2) are also connected. The mobile telephony system is assigned a frequency band which comprises a plurality of channels. The external part-system is divided into cells (C1, C2, C3) and has fixed channel assignment with a few channels to each external base stations (BS1, BS2). The internal part-system is adaptive and the internal base stations (BSI) have access to all channels of the system. In order to determine whether a mobile station (MSI) belongs to the internal or to the external part-system, an internal identification word is transmitted from the internal base stations and an external identification word is transmitted from the external base stations. When the signal strength of the internal identification word exceeds a threshold value, the moble station transmits an internal identification word to the internal base stations (BSI). If the signal strength falls beneath this treshold value, the mobile station (MSI) identifies itself to the external part-system (7). |
