Mobile communication system, mobile communication method, and radio station suitably used for the same

A radio station for carrying out multicast communication with a first mobile station belonging to a specific multicast group, the radio station comprising:

• a communication quality acquirer configured to acquire, from the first mobile station a communication quality of a signal transmitted from the radio station to the first mobile station, acquire a communication quality of a signal transmitted from a different radio station to a second mobile station belonging to the specific multicast group, and select the lowest communication quality from among the acquired communication qualities;
• a transmission method changer configured to determine a number of transmission signal repetitions by the multicast communication, in accordance with the selected lowest communication quality;
• and
• a transmitter configured to transmit the multicast communication to the first mobile station using the determined number of transmission signal repetitions.

A radio station for carrying out multicast communication with a first mobile station belonging to a specific multicast group, the radio station comprising:

• a communication quality acquirer configured to acquire, from the first mobile station a communication quality of a signal transmitted from the radio station to the first mobile station acquire, from a different radio station, a communication quality of a signal transmitted from the second radio station to a second mobile station belonging to the specific multicast group, and calculate an average value of the communication qualities acquired;
• a transmission method changer configured to determine a number of transmission signal repetitions by the multicast communication, in accordance with a difference between the calculated average value and a preset reference value;
• and
• a transmitter configured to transmit the multicast communication to the first mobile station using the determined number of transmission signal repetitions.

A mobile communication method for carrying out multicast communication, comprising:

• acquiring, at a first radio station, a communication quality of a signal transmitted from the first radio station to a first mobile station belonging to a specific multicast group;
• acquiring, at the first radio station, a communication quality of a signal transmitted from a second radio station to a second mobile station belonging to the specific multicast group;
• selecting a lowest communication quality from among the acquired communication qualities;
• determining, at the first radio station, a number of transmission signal repetitions by the multicast communication, in accordance with the selected lowest communication quality;
• and
• transmitting the multicast communication from the first radio station to the first mobile station using the determined number of transmission signal repetitions.

A mobile communication system which carries out multicast communication, comprising:

• a first radio station configured to carry out the multicast communication with a first mobile station belonging to a specific multicast group;
• a second radio station configured to carry out the multicast communication with a second mobile station belonging to the specific multicast group,
• wherein each of the first and second mobile stations include a communication quality measurer configured to measure a communication quality of a signal transmitted from each of the first and second radio stations, respectively;
• and
• the first radio station comprises:
• a communication quality acquirer configured to acquire the communication quality from the first mobile station belonging to the specific multicast group, acquire from the second radio station, a communication quality of a signal transmitted from the second radio station to the second mobile station belonging to the specific multicast group, and calculate an average value of the communication qualities acquired;
• a transmission method changer configured to determine a number of transmission signal repetitions by the multicast communication, in accordance with a difference between the calculated average value and a preset reference value;
• and
• a transmitter configured to transmit the multicast communication to the first mobile station using the determined number of transmission signal repetitions.

A mobile communication method for carrying out multicast communication, comprising:

• acquiring, at a first radio station, a communication quality of a signal transmitted from the first radio station to a first mobile station belonging to a specific multicast group;
• acquiring, at the first radio station, from a second radio station, a communication quality of a signal transmitted from the second radio station to a second mobile station belonging to the specific multicast group;
• calculating an average value of the communication qualities acquired;
• determining, at the first radio station, a number of transmission signal repetitions by the multicast communication, in accordance with a difference between the calculated average value and a preset reference value;
• and
• transmitting the multicast communication from the first radio station to the first mobile station using the determined number of transmission signal repetitions.