On-chip IQ imbalance and LO leakage calibration for transceivers
View Patent ↗The disclosure can provide methods and systems for autocalibrating a transceiver. The method can include upconverting a bandpass input signal by mixing the bandpass input signal with a first local oscillator signal to form an initial transmitter signal. The initial transmitter signal can be looped back to a receiver and downconverted with a second local oscillator signal having a frequency that is different from the first local oscillator to form an intermediate frequency signal. At least one of a gain and a phase of the transmitter can be adjusted based on a transmitter image sideband of the intermediate frequency signal to generate a calibrated transmitter signal having minimized transmitter image sideband.
1. A method of autocalibrating a transceiver, comprising:
looping back a first signal to a receiver of the transceiver;
bypassing one of a first path and a second path of the receiver;
processing the first signal to form a second signal; and
injecting a third signal to a complex receiver, the third signal being generated based on at least one of a fourth signal and a fifth signal, the fourth signal being generated based on the second signal.
2. The method of claim 1 , further comprising:
adjusting a transmitter of the transceiver based on the second signal to generate the fourth signal.
3. The method of claim 1 , further comprising:
processing the third signal in the complex receiver to form a sixth signal; and
adjusting the complex receiver based on the sixth signal to generate a seventh signal.
4. The method of claim 1 , further comprising:
upconverting a bandpass input signal by mixing the bandpass input signal with a signal of a first local oscillator to form the first signal.
5. The method of claim 4 , wherein the first local oscillator is at least one of an on-chip voltage controlled oscillator and a phase locked loop.
6. The method of claim 4 , wherein processing the first signal further comprises downconverting the first signal with a signal of a second local oscillator having a frequency that is different from the first local oscillator.
7. The method of claim 4 , further comprising:
downconverting the third signal by using the third signal with the first local oscillator.
8. The method of claim 2 , 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 second signal.
9. The method of claim 8 , further comprising:
separating the transmitter image sideband from the second signal;
separating a transmitter desired signal from the second signal; and
minimizing a power ratio of the transmitter image sideband to the transmitter desired signal.
10. The method of claim 8 , wherein adjusting the transmitter further comprises generating the fourth signal having reduced the transmitter image sideband.
11. A device for autocalibrating a transceiver, comprising:
a first circuit configured to route a first signal to a receiver of the transceiver;
a switch configured to bypass one of a first path and a second path of the receiver;
the receiver configured to process the first signal to form a second signal; and
a selector configured to inject a third signal into a complex receiver, the third signal being generated based on at least one of a fourth signal and a fifth signal, the fourth signal being generated based on the second signal.
12. The device of claim 11 , further comprising:
a second circuit configured to adjust a transmitter of the transceiver based on the second signal to generate the fourth signal.
13. The device of claim 11 , further comprising:
the complex receiver configured to process the third signal to form a sixth signal; and
a third circuit configured to adjust the complex receiver based on the sixth signal to generate a seventh signal.
14. The device of claim 11 , further comprising:
a processor configured to form the first signal and to upconvert a bandpass input signal by mixing the bandpass input signal with a signal of a first local oscillator.
15. The device of claim 14 , wherein the first local oscillator is at least one of an on-chip voltage controlled oscillator and a phase locked loop.
16. The device of claim 14 , wherein the receiver is further configured to downconvert the first signal with a signal of a second local oscillator having a frequency that is different from the first local oscillator.
17. The device of claim 14 , wherein the complex receiver is further configured to downconvert the third signal by using the third signal with the first local oscillator.
18. The device of claim 12 , 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 second signal.
19. The device of claim 18 , further comprising:
a first filter configured to separate the transmitter image sideband from the second signal;
a second filter configured to separate a transmitter desired signal from the second signal; and
a minimizer configured to minimize a power ratio of the transmitter image sideband to the transmitter desired signal.
20. The device of claim 18 , wherein the second circuit is further configured to generate the fourth signal having reduced the transmitter image sideband.