COMMUNICATION METHOD, BASE STATION, COMMUNICATION SYSTEM, AND MOBILE TERMINAL

• US 20100046451A1
• Filed: 02/01/2008
• Published: 02/25/2010
• Est. Priority Date: 02/02/2007
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Maeda, Miho, Iwane, Yasushi, Mochizuki, Mitsuru, Tada, Keiko
• Granted Patent: US 9,161,181 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 4/10 Push-to-Talk [PTT] or Push-On-Call services
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 72/1263 Mapping of traffic onto schedule, e.g. scheduled allocation or multiplexing of flows
• CPC Class Codes: H04W 72/30 Resource management for broadcast services
• CPC Class Codes: H04W 76/20 Manipulation of established connections
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: H04W 76/45 for Push-to-Talk [PTT] or Push-to-Talk over cellular [PoC] services
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

In accordance with the present invention, in a case of using persistent scheduling, when detecting a transition from a talk state to a silent state, resources to be allocated during a silent state are allocated to a channel exclusive for silent period, and the resources which have been allocated to a mobile terminal during the talk spurt are released. Therefore, the useless allocation of resources can be reduced, and the throughput of the system can be improved.

Claims

1. A data communication method which is executed by a communication system including a base station which performs a persistent scheduling process of transmitting a scheduling result in a predetermined notification cycle, and which transmits and receives packet data by using an OFDM (Orthogonal Frequency Division Multiplexing) method as a downlink access method, and a mobile terminal which transmits a scheduling request signal with which to make a request of said base station for allocation of radio resources, and which transmits and receives said packet data by using radio resources allocated thereto by said base station, characterized in that said data communication method comprises:

a talk state judging process of, when there exists voice information to be transmitted to said mobile terminal, judging whether state is either a talk state in which said base station transmits said voice information as voice packet data or a silent state in which said base station transmits background noise data as said voice packet data;

a notification process of notifying both talk-spurt radio resources available to said talk spurt and silent-period radio resources available to said silent state to said mobile terminal at a time of initial transmission between said base station and said mobile terminal; and

a radio resource allocating process of allocating said talk-spurt radio resources to another mobile terminal when detecting a transition from said talk state to said silent state through said talk state judging process.

2. The communication method according to claim 1, characterized in that the silent-period radio resources includes a parameter indicating a frequency region and a time region of a channel exclusive for silent period which is disposed for transmission of voice packet data including background noise data.

3. The communication method according to claim 1, characterized in that the silent-period radio resources include a parameter indicating a frequency region and a time region which specify a resource block, among the talk-spurt radio resources, to which voice packet data including background noise data are allocated.

4. The communication method according to claim 1, characterized in that when voice packet data to be transmitted from the mobile terminal to the base station occur, a radio resource which is allocated to transmission of said voice packet data is determined by using frequency hopping.

5. The communication method according to claim 1, characterized in that the persistent scheduling process includes a step of performing scheduling according to the scheduling request signal transmitted from the mobile terminal, and a step of notifying a scheduling result at an arbitrary timing independent of the notification cycle of the persistent scheduling process.

6. The communication method according to claim 5, characterized in that the communication method includes a step of transmitting the scheduling request signal, and also receiving the scheduling result at an arbitrary timing independent of the notification cycle of the persistent scheduling process performed by the base station.

7. The communication method according to claim 1, characterized in that the notification process is the one of including the talk-spurt radio resources and the silent-period radio resources in an L3 control signal which is a control signal notified from an upper layer so as to notify the talk-spurt radio resources and the silent-period radio resources.

8. A base station which performs a persistent scheduling process of transmitting a scheduling result in a predetermined notification cycle, and which transmits and receives packet data by using an OFDM (Orthogonal Frequency Division Multiplexing) method as a downlink access method, characterized in that said base station comprises:

a notification processing unit for notifying both talk-spurt radio resources available to a talk state in which said base station transmits said voice information as voice packet data and silent-period radio resources available to a silent state in which said base station transmits background noise data as said voice packet data to said mobile terminal at a time of initial transmission to said mobile terminal; and

a control unit for judging whether state is either said talk state or said silent state, and for performing a radio resource allocating process of allocating said talk-spurt radio resources to another mobile terminal when detecting a transition from said talk state to said silent state.

9. A communication system including a base station which performs a persistent scheduling process of transmitting a scheduling result in a predetermined notification cycle, and which transmits and receives packet data by using an OFDM (Orthogonal Frequency Division Multiplexing) method as a downlink access method, and a mobile terminal which transmits a scheduling request signal with which to make a request of said base station for allocation of radio resources, and which transmits and receives said packet data by using radio resources allocated thereto by said base station, characterized in that said communication system comprises:

a base station including a notification processing unit for notifying both talk-spurt radio resources available to a talk state in which said base station transmits said voice information as voice packet data and silent-period radio resources available to a silent state in which said base station transmits background noise data as said voice packet data to said mobile terminal at a time of initial transmission between said base station and said mobile terminal, and a control unit for judging whether state is either said talk state or said silent state, and for performing a radio resource allocating process of allocating said talk-spurt radio resources to another mobile terminal when detecting a transition from said talk state to said silent state; and

a mobile terminal including a receiving unit for receiving said voice packet data by using said silent-period radio resources when said base station detects a transition from said talk state to said silent state.

10. A mobile terminal which transmits a scheduling request signal with which to make a request of a base station which transmits and receives packet data by using an OFDM (Orthogonal Frequency Division Multiplexing) method as a downlink access method for allocation of radio resources, and which transmits and receives said packet data by using radio resources allocated thereto by said base station, characterized in that

said mobile terminal transmits said scheduling request signal, and also performs continuous reception in such a way as to receive a scheduling result at an arbitrary timing independent of a notification cycle of a persistent scheduling process performed by said base station.