MOBILE COMMUNICATION SYSTEM, TRANSMISSION-SIDE TERMINAL, MOBILE COMMUNICATION METHOD AND PROCESSOR

• US 20150373616A1
• Filed: 06/25/2013
• Published: 12/24/2015
• Est. Priority Date: 06/27/2012
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: FUJISHIRO, Masato
• Granted Patent: US 9,532,294 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 2001/0097 Relays
• CPC Class Codes: H04W 40/12 based on transmission quality or channel quality
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 92/18 between terminal devices

Abstract

The mobile communication system directly performs user-data communication between a plurality of radio terminals without involvement of a radio base station. The user-data communication directly performed between the plurality of radio terminals is performed by using a part of radio resources assigned to the mobile communication system. The plurality of radio terminals comprise: a transmission-side terminal that transmits the user data; and a reception-side terminal that receives the user data. The reception-side terminal comprises: a reception-side transmission unit that transmits a transmission acknowledgement signal indicating whether the user data transmitted from the transmission-side terminal has been able to receive or not. The reception-side transmission unit transmits the transmission acknowledgement signal to the radio base station.

Claims

1. A mobile communication system, in which user-data communication between a plurality of radio terminals is directly performed without involvement of a radio base station, wherein

the user-data communication directly performed between the plurality of radio terminals is performed by using a part of radio resources assigned to the mobile communication system,

the plurality of radio terminals comprise:

a transmission-side terminal that transmits the user data; and

a reception-side terminal that receives the user data,

the reception-side terminal comprises;

a reception-side transmission unit that transmits a transmission acknowledgement signal indicating whether the user data transmitted from the transmission-side terminal has been able to receive or not, and

the reception-side transmission unit transmits the transmission acknowledgement signal to the radio base station.

2. The mobile communication system according to claim 1, wherein, when a communication state of the user data directly performed between the plurality of radio terminals is poor, the reception-side transmission unit transmits the transmission acknowledgement signal to the radio base station.

3. The mobile communication system according to claim 2, wherein the radio base station comprises:

a base station-side transmission unit that transmits the transmission acknowledgement signal to the transmission-side terminal.

4. The mobile communication system according to claim 1, wherein the radio base station comprises:

a base station-side control unit that assigns, as a reception resource for receiving the user data, the radio resource assigned to the user-data communication directly performed between the plurality of radio terminals.

5. The mobile communication system according to claim 4, wherein the radio base station comprises:

a base station-side transmission unit that transmits the transmission acknowledgement signal to the transmission-side terminal, wherein

the base station-side control unit determines whether to transmit the transmission acknowledgement signal to the transmission-side terminal on the basis of a reception state of the user data received by using the reception resource.

6. The mobile communication system according to claim 4, wherein the radio base station comprises:

a base station-side transmission unit that retransmits the user data, which is received by using the reception resource, to the reception-side terminal on the basis of the transmission acknowledgement signal.

7. A transmission-side terminal that transmits user data to a reception-side terminal, of a plurality of radio terminals, in a mobile communication system in which the user-data communication between the plurality of radio terminals is directly performed without involvement of a radio base station, wherein the user-data communication directly performed between the plurality of radio terminals is performed by using a part of radio resources assigned to the mobile communication system, comprising:

a transmission-side reception unit that receives a transmission acknowledgement signal indicating whether the reception-side terminal has been able to receive the user data, wherein

the transmission-side reception unit directly receives the transmission acknowledgement signal from the reception-side terminal and receives the transmission acknowledgement signal via the radio base station.

8. The transmission-side terminal according to claim 7, comprising:

a transmission-side control unit that determines whether to retransmit, to the reception-side terminal, the user data received by using the reception resource, on the basis of the transmission acknowledgement signal, wherein,

when a communication state of the user data directly performed between the plurality of radio terminals is good, the transmission-side control unit refers to the transmission acknowledgement signal directly received from the reception-side terminal without referring to the transmission acknowledgement signal received via the radio base station.

9. The transmission-side terminal according to claim 7, comprising:

a transmission-side control unit that determines whether to retransmit, to the reception-side terminal, the user data received by using the reception resource, on the basis of the transmission acknowledgement signal, wherein

the transmission-side control unit notifies the radio base station of whether to refer to the transmission acknowledgement signal received via the radio base station.

10. A mobile communication method used in a mobile communication system in which user-data communication between a plurality of radio terminals is directly performed without involvement of a radio base station, wherein

the user-data communication directly performed between the plurality of radio terminals is performed by using a part of radio resources assigned to the mobile communication system,

the plurality of radio terminals comprise:

a transmission-side terminal that transmits the user data; and

a reception-side terminal that receives the user data,

the mobile communication method comprises;

a step A of transmitting, by the reception-side terminal, a transmission acknowledgement signal indicating whether the user data transmitted from the transmission-side terminal has been able to receive or not, and

the step A comprises;

a step of transmitting the transmission acknowledgement signal to the radio base station.

11. A processor for causing a transmission-side terminal to perform a process, the transmission-side terminal transmitting user data to a reception-side terminal, of a plurality of radio terminals, in a mobile communication system in which the user-data communication between the plurality of radio terminals is directly performed without involvement of a radio base station, wherein

the user-data communication directly performed between the plurality of radio terminals is performed by using a part of radio resources assigned to the mobile communication system,

the processor causes the transmission-side terminal to perform a process A of receiving a transmission acknowledgement signal indicating whether the reception-side terminal has been able to receive the user data,

the process A comprises:

a process of directly receiving the transmission acknowledgement signal from the reception-side terminal and receiving the transmission acknowledgement signal via the radio base station.