Power efficient control of uplink carrier usage by mobile terminal

1. A method of data transmission between a mobile terminal and a cellular network, the method comprising:

establishing a downlink connection from the cellular network to the mobile terminal, said downlink connection using one or more downlink carriers;

identifying multiple uplink carriers which are available for establishing an uplink connection from the mobile terminal to the cellular network;

a network component sending a request to the mobile terminal, the request triggering measurements of transmit power performed by the mobile terminal while controlling the mobile terminal to have a minimum transmit activity on the uplink carriers;

in response to the request, the network component receiving at least one report of the measurements performed by the mobile terminal, the at least one report indicating, for each of the uplink carriers, a transmit power being required for performing an uplink transmission on the uplink carrier;

based on the transmit powers, the network component estimating impact of usage of the uplink carriers on power consumption of the mobile terminal; and

depending on the estimated impact, selecting at least one of the uplink carriers for establishing the uplink connection.

2. The method according to claim 1 , comprising:

selecting at least two of the uplink carriers for establishing the uplink connection; and

depending on the estimated impact, the network component deciding to schedule an uplink transmission on one of the at least two uplink carriers.

3. The method according to claim 1 ,

wherein the uplink carriers are received by at least two different base stations of the cellular network.

4. The method according to claim 1 ,

wherein at least two of the uplink carriers are received by the same base station of the cellular network.

5. A method of data transmission between a mobile terminal and a cellular network, the method comprising:

the mobile terminal establishing a downlink connection from the cellular network to the mobile terminal, said downlink connection using one or more downlink carriers;

the mobile terminal identifying multiple uplink carriers which are available for establishing an uplink connection from the mobile terminal to the cellular network;

the mobile terminal receiving a request for a measurement report from the cellular network

in response to the request the mobile terminal measuring a transmit power of the mobile terminal for each of the uplink carriers, while the mobile terminal is controlled to have a minimum transmit activity on the uplink carriers, the transmit power being required for performing an uplink transmission on the uplink carrier; and

the mobile terminal sending at least one measurement report indicating the measured transmit powers to the cellular network.

6. A network component for a cellular network, the network component comprising

an interface for establishing a downlink connection to a mobile terminal, said downlink connection using one or more downlink carriers; and

a processor, the processor being configured to:

identify multiple uplink carriers which are available for establishing an uplink connection from the mobile terminal to the cellular network;

send a request to the mobile terminal, the request triggering measurements of transmit power performed by the mobile terminal while controlling the mobile terminal to have a minimum transmit activity on the uplink carriers;

in response to the request, receive at least one report of the measurements performed by the mobile terminal, the at least one report indicating, for each of the uplink carriers, a transmit power being required for performing an uplink transmission on the uplink carrier;

based on the transmit powers, estimate impact of usage of the uplink carriers on power consumption of the mobile terminal; and

depending on the estimated impact, select at least one of the uplink carriers for establishing the uplink connection.

7. The network component according to claim 6 ,

wherein the processor is further configured to:

select at least two of the uplink carriers for establishing the uplink connection, and

depending on the estimated impact, decide to schedule an uplink transmission on one of the at least two uplink carriers.

8. The network component according to claim 6 ,

wherein the uplink carriers are to be received by at least two different base stations of the cellular network.

9. The network component according to claim 6 ,

wherein at least two of the uplink carriers are to be received by the same base station of the cellular network.

10. The network component according to claim 6 ,

wherein the interface is a radio interface and is configured for transmitting the at least one downlink carrier.

11. The network component according to claim 10 ,

wherein the interface is further configured for receiving at least one of the uplink carriers.

12. A mobile terminal, comprising:

a radio interface for establishing a downlink connection from a cellular network to the mobile terminal, said downlink connection using one or more downlink carriers, and for establishing an uplink connection from the mobile terminal to the cellular network; and

a processor, wherein the processor is configured to:

identify multiple uplink carriers which are available for establishing the uplink connection;

receive a request for a measurement report from the cellular network;

in response to the request, measure a transmit power of the mobile terminal for each of the uplink carriers, while the mobile terminal is controlled to have a minimum transmit activity on the uplink carriers, the transmit power being required for performing an uplink transmission on the uplink carrier; and

send at least one measurement report indicating the measured transmit powers to the cellular network.