Patent ID: 8457640

Claim:
A handoff access method based on a random access channel for handoff access of a mobile terminal of a cellular mobile communication system, the method comprising: sending a handoff request message to a target Base Station (BS) by a source BS, the handoff request message being used to request switching a mobile terminal that the source BS serves to the target BS; sending a handoff response message to the source BS by the target BS, then forwarding, a handoff command message with content of the handoff response message to the mobile terminal by the source BS, wherein the handoff command message does not include a reserved character code, and the reserved character code is one of a first part of random access character codes separately allocated to the mobile terminal and other mobile terminals in advance; after receiving the handoff command message by the mobile terminal, based on a determination that the handoff command message excludes the reserved character code, selecting a random access sub-channel; based on a determination by the mobile terminal that the reserved character code is reserved on the selected random access sub-channel, the mobile terminal selecting a non-reserved character code and then selecting the random access sub-channel that the non-reserved character code is located in, wherein the non-reserved character code is a random access character code selected from a remaining part of the random access character codes; and initiating a handoff access procedure on the random access sub-channel by the mobile terminal.