Compensating amplifier phase in a diversity receiver front end

1. A method for phase-shifting signals in a receiving system, the method comprising:

receiving a band select signal indicating one or more frequency bands;

activating one or more of a plurality of paths through the receiving system based on the band select signal, the plurality of paths including a first path corresponding to a first frequency band and a second path corresponding to a second frequency band;

sending a tuning signal to a first phase-shifting component on the first path and to a second phase-shifting component on the second path; and

phase-shifting the second frequency band of a signal passing through the first phase-shift component using the first phase-shifting component, a phase-shift at the second frequency band of the first phase-shifting component based on a phase-shift caused by one or more components on the first path at the second frequency band.

2. The method of claim 1 further comprising amplifying the first frequency band of a signal on the first path with a first amplifier.

3. The method of claim 2 wherein the first amplifier causes a phase-shift at the second frequency band.

4. The method of claim 3 wherein the phase-shift of the first phase-shifting component is based on a phase-shift caused by reverse propagation through the first amplifier and forward propagation through the first amplifier.

5. The method of claim 2 further comprising phase-shifting a third frequency band of the signal passing through the first phase-shift component using the first phase-shifting component, a phase-shift at the third frequency band of the first phase-shifting component based on a phase-shift caused by the first amplifier at the third frequency band.

6. The method of claim 1 further comprising amplifying the second frequency band of a signal on the second path with a second amplifier.

7. The method of claim 6 further comprising phase-shifting the first frequency band of a signal passing through the second phase-shift component using the second phase-shift component, a phase-shift at the first frequency band of the second phase-shift component based on a phase-shift caused by the second amplifier at the first frequency band.

8. The method of claim 7 wherein the phase-shift at the first frequency band of the second phase-shifting component is based on a phase-shift caused by reverse propagation through the second amplifier and forward propagation through the second amplifier.

9. The method of claim 1 further comprising splitting an input signal received at an input of the receiving system into a first signal at the first frequency band propagated along the first path and a second signal at the second frequency band propagated along the second path.

10. The method of claim 9 further comprising combining the first signal and the second signal.

11. The method of claim 1 wherein activating the one or more paths includes enabling or disabling amplifiers disposed along the one or more paths.

12. The method of claim 1 wherein the phase-shift at the second frequency band of the first phase-shift component is configured so that an initial signal propagated along the second path and a reflected signal propagated along the first path are at least partially in-phase.

13. The method of claim 12 wherein the phase-shift at the second frequency band of the first phase-shift component is configured so that an amplitude of a sum of an initial signal and the reflected signal is greater than an amplitude of the initial signal.

14. A method for phase-shifting signals in a receiving system, the method comprising:

receiving a band select signal indicating one or more frequency bands;

activating one or more of a plurality of paths through the receiving system based on the band select signal, the plurality of paths including a first path corresponding to a first frequency band and a second path corresponding to a second frequency band;

sending a tuning signal to a first phase-shifting component on the first path and to a second phase-shifting component on the second path; and

phase-shifting the second frequency band of a signal on the first path using the first phase-shifting component such that a first initial signal propagated along the second path and a first reflected signal propagated along the first path are at least partially in-phase.

15. The method of claim 14 further comprising amplifying the first frequency band of a signal on the first path with a first amplifier.

16. The method of claim 15 wherein the first amplifier causes a phase-shift at the second frequency band.

17. The method of claim 14 wherein further comprising phase-shifting the second frequency band of a signal on the second path using the second phase-shifting component such that a second initial signal propagated along the first path and a second reflected signal propagated along the second path are at least partially in-phase.

18. The method of claim 14 further comprising phase-shifting a third frequency band of a signal on the first path using the first phase-shifting component such that a third initial signal propagated along a third path of the plurality of paths corresponding to the third frequency band and a third reflected signal propagated along the first path are at least partially in-phase.

19. The method of claim 14 wherein the phase-shift at the second frequency band of the first phase-shift component is configured so that the first initial signal and the first reflected signal have a phase difference of an integer multiple of 360 degrees.

20. The method of claim 14 further comprising decreasing at least one of an out-of-band noise figure or an out-of-band gain of signals propagating along the one or more activated paths.