Current reduction by dynamic receiver adjustment in a communication device

1. A method for reducing current drain in a communication device, the method comprising the steps of:

detecting interference;

determining a frequency offset of the interference;

measuring a power level of the interference;

calculating a receiver linearity required to achieve a desired signal-to-interference ratio; and

adjusting the receiver linearity calculated in the calculating step to achieve the desired signal-to-interference ratio.

2. A method as recited in claim 1 , further comprising the step of operating the communication device in a code division multiple access (CDMA) system.

3. A method as recited in claim 1 , wherein the determining step includes estimating a signal spectrum of the interference products to determine the frequency offset of interference products and whether interference products are present within a receiver passband.

4. A method as recited in claim 1 , wherein the determining step includes estimating a signal spectrum of the interference products to determine the frequency offset of interference products and whether interference products exceed a noise spectrum threshold within a receiver passband.

5. A method as recited in claim 1 , wherein the measuring step includes an attenuation factor of the receiver at the frequency offset.

6. A method as recited in claim 1 , wherein the adjusting step includes adjusting an analog-to-digital converter dynamic range to a level corresponding to the adjusted receiver linearity.

7. A method as recited in claim 1 , wherein the measuring step includes measuring a transmit power level and frequency offset of the communication device, and wherein the desired signal-to-interference ratio of the calculating step is dependent upon the transmit power level and frequency offset.

8. A method as recited in claim 1 , wherein the adjusting step include setting at least one of the group of current and gain to the receiver at a minimum level sufficient to achieve the desired signal-to-interference ratio.

9. A method as recited in claim 1 , wherein the adjusting step include setting at least one of the group of current and gain to the receiver at a minimum level sufficient to achieve the desired linearity and dynamic range for the desired signal-to-interference ratio.

10. A communication device with reduced current drain, the communication device comprising:

a transmitter operable at a variable transmit power level;

a receiver operable with variable linearity; and

a control circuit coupled to the transmitter and receiver, the control circuit operable to detect interference and control the receiver linearity, wherein if interference is detected the control circuit;

determines a frequency offset of the interference;

measures a power level of the interference;

calculates a receiver linearity required to achieve a desired signal-to-interference ratio; and

adjusts the receiver linearity to achieve the desired signal-to-interference ratio.

11. A communication device as recited in claim 10 , wherein the control circuit estimates a signal spectrum of the interference products to determine whether interference products exceed a noise spectrum threshold within a receiver passband.

12. A communication device as recited in claim 10 , wherein the control circuit adjusts a dynamic range of the receiver in accordance with the adjusted receiver linearity.

13. A communication device as recited in claim 10 , wherein the control circuit adjusts at least one of the group of current and gain to the receiver at a minimum level sufficient to achieve the desired signal-to-interference ratio.

14. A communication device as recited in claim 10 , wherein the control circuit calculates a third-order intercept point threshold to provide sufficient signal-to-interference and sets at least one of the group of current and gain to the receiver at a level sufficient to at least meet the third-order intercept point threshold.