A CDMA cellular communication system and method of access therefor

摘要

This invention relates to a CDMA cellular communication system. Known CDMA systems perform call access to only one base station. According to the current invention a subscriber unit comprises means for entering a multiple cell access mode (409). It furthermore comprise means (411,413) for transmitting two preamble parts (601) of a preamble message to two different base stations when in this mode. The subscriber unit subsequently detects acknowledge signals (603,605) from the two base stations and controls means (417) for transmitting a message part (609) of the access message in response to these acknowledge messages (603,605). Specifically, the transmit power levels of the message part (609) is set to enable communication to the corresponding base station if only one message is received and to both base stations if two acknowledge signals (603,605) are received. The invention is applicable to 3<rd> generation cellular communication systems such as UMTS. <IMAGE>