Mobile station capable of switching connection destination radio base station and method of switching connection destination

1. A mobile station which is capable of connecting to a plurality of radio base stations and which is currently communicating with a currently-communicating radio base station from among the plurality of radio base stations, the mobile station comprising:

a quality memory unit that remembers a quality table in which different quality levels of communication with the radio base stations are arranged according to identification information of the radio base stations;

a processing unit that determines, based on the quality table in said quality memory unit, a selecting radio base station to select a switching radio base station to be a connection destination after switching and sending the quality table to the selecting radio base station when switching connection destination radio base stations; and

a connecting unit that sends a connection request to the switching radio base station specified by the identification information, if identification information of the switching radio base station selected by the selecting radio base station according to the quality table sent from said processing unit is received,

wherein the currently-communicating radio base station is different from the selecting radio base station.

2. The mobile station according to claim 1 , wherein said processing unit determines a radio base station specified by the identification information corresponding to best quality level of radio communication from among the different quality levels in quality table as said selecting radio base station.

3. The mobile station according to claim 1 , wherein

said processing unit sends the quality table and the connection request to the selecting radio base station, and

said connecting unit, if the identification information and rejection information notifying rejection of the connection request sent from said processing unit are received, sends the connection request to said switching radio base station, and if approval information notifying approval of the connection request sent from said processing unit is received, connects to said selecting radio base station.

4. The mobile station according to claim 1 , wherein said connection unit sends the connection request and the quality table to said switching radio base station, if identification information of a new switching radio base station selected by the switching radio base station according to the quality table and rejection information notifying rejection of the connection request are received, sends the connection request to said new switching radio base station, and if approval information notifying approval of the connection request sent to said switching radio base station is received, connects to said switching radio base station.

5. A method of switching connection destinations by a mobile station, which is capable of connecting to a plurality of radio base stations and which includes quality memory unit remembering a quality table in which different quality levels of communication with the radio base stations are arranged according to identification information of the radio base stations, wherein the mobile station is currently communicating with a currently-communicating radio base station from among the plurality of radio base stations, the method comprising:

determining, based on the quality table in the quality memory unit, a selecting radio base station to select a switching radio base station to be a connection destination after switching and sending the quality table to the selecting radio base station when switching connection destination radio base stations; and

if identification information of the switching radio base station selected by the selecting radio base station according to the quality table sent from the processing unit is received, sending a connection request to the switching radio base station specified by the identification information,

wherein the currently-communicating radio base station is different from the selecting radio base station.

6. The method according to claim 5 , wherein determining a radio base station specified by identification information corresponding to the best quality level of radio communication as the selecting radio base station.

7. The method according to claim 5 , comprising:

determining a selecting radio base station sending the quality table and the connection request to the selecting radio base station, and

if the identification information and rejection information notifying rejection of the connection request sent from the processing unit is received, sending the connection request to the switching radio base station, and if approval information notifying approval of the connection request sent from the processing unit is received, connecting to the selecting radio base station.

8. The method according to claim 5 , comprising:

sending the connection request and the quality table to the switching radio base station, and

if identification information of a new switching radio base station selected by the switching radio base station according to the quality table and rejection information notifying rejection of the connection request are received, sending the connection request to the new switching radio base station, and if approval information notifying approval of the connection request sent to the switching radio base station is received, connecting to the switching radio base station.