Method and apparatus for transmitting PUCCH with a lower A-MPR

1. A method comprising:

ascertaining, at a device, a first additional maximum power reduction for a first resource block of a physical uplink control channel transmission if the device is configured for carrier aggregation transmission;

ascertaining a second additional maximum power reduction for a second resource block of a physical uplink control channel transmission if the device is configured for carrier aggregation transmission;

determining a first applied additional maximum power reduction as the maximum of the first additional maximum power reduction and the second additional maximum power reduction if the device is configured for carrier aggregation;

ascertaining a third additional maximum power reduction for a first resource block of a physical uplink control channel transmission if the device is configured for transmission only on a primary cell;

ascertaining a fourth additional maximum power reduction for a second resource block of a physical uplink control channel transmission if the device is configured for transmission only on the primary cell;

determining a second applied additional maximum power reduction as the maximum of the third additional maximum power reduction and the fourth additional maximum power reduction if the device is configured for transmission only on the primary cell;

configuring a transmitter for carrier aggregation transmission if the first applied additional maximum power reduction is less than or equal to the second applied additional maximum power reduction;

configuring the transmitter for transmission only on the primary cell if the second applied additional maximum power reduction is less than the first applied additional maximum power reduction; and

transmitting the uplink control channel with a power reduction no greater than the applied additional maximum power reduction for the selected transmitter configuration.

2. The method according to claim 1 , wherein the transmitter is configured for carrier aggregation if the frequency of a local oscillator is in the center of the aggregated carriers.

3. The method according to claim 1 , wherein the transmitter is configured for carrier aggregation if the frequency of a local oscillator of the transmitter is in the center of a carrier of the primary cell.

4. The method according to claim 1 , further comprising moving a frequency of a local oscillator of the transmitter within a given time interval.

5. The method according to claim 4 , wherein moving comprises moving a frequency of a local oscillator of the transmitter to the center of a primary cell component carrier on which the physical uplink control channel is being transmitted.

6. The method according to claim 5 , further comprising applying the second additional A-MPR for the component carrier on which the PUCCH is transmitted if the device is configured for transmission only on the primary cell component carrier.

7. The method of claim 4 , further comprising signaling, to a network, the time interval needed to move the frequency of the local oscillator.

8. An apparatus comprising:

a controller that

ascertains, at a device, a first additional maximum power reduction for a first resource block of a physical uplink control channel transmission if the device is configured for carrier aggregation transmission,

ascertains a second additional maximum power reduction for a second resource block of a physical uplink control channel transmission if the device is configured for carrier aggregation transmission,

determines a first applied additional maximum power reduction as the maximum of the first additional maximum power reduction and the second additional maximum power reduction if the device is configured for carrier aggregation,

ascertains a third additional maximum power reduction for a first resource block of a physical uplink control channel transmission if the device is configured for transmission only on a primary cell,

ascertains a fourth additional maximum power reduction for a second resource block of a physical uplink control channel transmission if the device is configured for transmission only on the primary cell,

determines a second applied additional maximum power reduction as the maximum of the third additional maximum power reduction and the fourth additional maximum power reduction if the device is configured for transmission only on the primary cell,

configures a transmitter for carrier aggregation transmission if the first applied additional maximum power reduction is less than or equal to the second applied additional maximum power reduction, and

configures the transmitter for transmission only on the primary cell if the second applied additional maximum power reduction is less than the first applied additional maximum power reduction; and

a transceiver coupled to the controller, where the transceiver transmits the uplink control channel with a power reduction no greater than the applied additional maximum power reduction for the selected transmitter configuration.

9. The apparatus according to claim 8 , wherein the transmitter is configured for carrier aggregation if the frequency of a local oscillator is in the center of the aggregated carriers.

10. The apparatus according to claim 8 , wherein the transmitter is configured for carrier aggregation if the frequency of a local oscillator of the transmitter is in the center of a carrier of the primary cell.

11. The apparatus according to claim 8 , further comprising moving a frequency of a local oscillator of the transmitter within a given time interval.

12. The apparatus according to claim 11 , wherein moving comprises moving a frequency of a local oscillator of the transmitter to the center of a primary cell component carrier on which the physical uplink control channel is being transmitted.

13. The apparatus according to claim 12 , further comprising applying the second additional A-MPR for the component carrier on which the PUCCH is transmitted if the device is configured for transmission only on the primary cell component carrier.

14. The apparatus according to claim 11 , further comprising signaling, to a network, the time interval needed to move the frequency of the local oscillator.