On-Chip IQ imbalance and LO leakage calibration for transceivers

1. A method of autocalibrating a transceiver, comprising:

forming an initial transmitter signal;

looping back the initial transmitter signal to a receiver of the transceiver;

bypassing one of an inphase path and a quadrature path of the receiver;

processing the received initial transmitter signal to form an intermediate frequency signal;

adjusting a transmitter of the transceiver based on the intermediate frequency signal to generate a calibrated transmitter signal;

injecting a test signal from at least one of the calibrated transmitter signal and a bandpass signal source into a complex receiver;

processing the test signal in the complex receiver to form a complex baseband signal; and

adjusting the complex receiver based on the complex baseband signal to generate a calibrated receiver signal.

2. The method of claim 1 , wherein forming the initial transmitter signal further comprises upconverting a bandpass input signal by mixing the bandpass input signal with a first signal of a first local oscillator.

3. The method of claim 2 , wherein processing the initial transmitter signal further comprises downconverting the initial transmitter signal with a second signal of a second local oscillator having a frequency that is different from the first local oscillator.

4. The method of claim 2 , wherein processing the test signal further comprises downconverting the test signal by using the test signal with the first local oscillator.

5. The method of claim 1 , wherein adjusting the transmitter further comprises adjusting at least one of a gain and a phase of the transmitter based on a transmitter image sideband of the intermediate frequency signal.

6. The method of claim 5 , further comprising:

separating the transmitter image sideband from the intermediate frequency signal;

separating a transmitter desired signal from the intermediate frequency signal; and

minimizing a power ratio of the transmitter image sideband to the transmitter desired signal.

7. The method of claim 5 , wherein adjusting the transmitter further comprises generating the calibrated transmitter signal having reduced the transmitter image sideband.

8. The method of claim 7 , wherein generating the calibrated transmitter signal includes at least one of minimizing a transmitter image sideband power spectral density and transmitter image sideband power.

9. The method of claim 1 , wherein adjusting the complex receiver further comprises adjusting at least one of a gain and a phase of the complex receiver based on a receiver image sideband of the complex baseband signal.

10. The method of claim 9 , wherein adjusting the complex receiver further comprises generating the calibrated receiver signal having reduced the receiver image sideband.

11. A device for autocalibrating a transceiver, comprising:

a processor configured to form an initial transmitter signal;

a first circuit configured to route the initial transmitter signal to a receiver of the transceiver;

a switch configured to bypass one of an inphase path and a quadrature path of the receiver;

the receiver configured to process the initial transmitter signal to form an intermediate frequency signal;

a second circuit configured to adjust a transmitter of the transceiver based on the intermediate frequency signal to generate a calibrated transmitter signal;

a selector configured to inject a test signal from at least one of the calibrated transmitter signal and a bandpass signal source into a complex receiver;

the complex receiver configured to process the test signal to form a complex baseband signal; and

a third circuit configured to adjust the complex receiver based on the complex baseband signal to generate a calibrated receiver signal.

12. The device of claim 11 , wherein the processor is further configured to upconvert a bandpass input signal by mixing the bandpass input signal with a first signal of a first local oscillator.

13. The device of claim 12 , wherein the receiver is further configured to downconvert the initial transmitter signal with a second signal of a second local oscillator having a frequency that is different from the first local oscillator.

14. The device of claim 12 , wherein the complex receiver is further configured to downconvert the test signal by using the test signal with the first local oscillator.

15. The device of claim 11 , wherein the second circuit is further configured to adjust at least one of a gain and a phase of the transmitter based on a transmitter image sideband of the intermediate frequency signal.

16. The device of claim 15 , further comprising:

a first filter configured to separate the transmitter image sideband from the intermediate frequency signal;

a second filter configured to separate a transmitter desired signal from the intermediate frequency signal; and

a minimizer configured to minimize a power ratio of the transmitter image sideband to the transmitter desired signal.

17. The device of claim 15 , wherein the second circuit is further configured to generate the calibrated transmitter signal having reduced the transmitter image sideband.

18. The device of claim 17 , wherein the second circuit is further configured to generate the calibrated transmitter signal by minimizing at least one of a transmitter image sideband power spectral density and transmitter image sideband power.

19. The device of claim 11 , wherein the third circuit is further configured to adjust at least one of a gain and a phase of the complex receiver based on a receiver image sideband of the complex baseband signal.

20. The device of claim 19 , wherein the third circuit is further configured to generate the calibrated receiver signal having reduced the receiver image sideband.