Patent ID: 8457065

Claim:
A handover method in a wireless communication system performing handover of a mobile station from a connected base station to a neighbor base station, the method comprising: deciding, in the mobile station, to perform neighbor base station information non-reception handover if the mobile station has not received neighbor base station information relating to neighbor base stations from the connected base station and if a radio wave strength of radio waves from the connected base station is below a threshold value; searching for a connectable neighbor base station based on frequencies stored in a table in the mobile station if a decision is made that the neighbor base station information non-reception handover is to be performed; acquiring, in the mobile station, identification information for a neighbor base station from the connectable neighbor base station search; transmitting, by the mobile station, a handover request including the acquired identification information to the connected base station; transmitting, by the connected base station that received the handover request, to the mobile station, service level information included with a handover response, the service level information indicating information as to what extent a service flow can be handed over from the connected base station to the neighbor base station; and acquiring, in the mobile station, the service level information from the handover response, and deciding a handover destination based on the service level information, wherein the decision to perform the neighbor base station information non-reception handover is established if a calculation is made that the mobile station moves out of the cell of the connected base station without receiving the neighbor base station information based on: a size of the cell estimated from the strength of radio wave from the connected base station, a movement velocity of the mobile station, and a transmission interval of the neighbor base station information.