Wireless backhaul
In the subject system, a receiver includes a feed forward circuit, a phase recovery circuit, and a feedback circuit. The feed forward circuit compensates for near reflections and provides an input to the phase recovery circuit and the feedback circuit. The phase recovery circuit performs phase recovery and provides phase recovery information to the feedback circuit. The feedback circuit adjusts and/or corrects a received symbol based at least in part on the received phase recovery information.
1. A system comprising:
a feedback equalizer operable to receive a wirelessly transmitted signal, wherein the feedback equalizer is operable to adjust a current symbol in the wirelessly transmitted signal according to phase recovery information; and
a phase recovery circuit comprising an adaptive filter, wherein the phase recovery circuit is operable to generate the phase recovery information according to the wirelessly transmitted signal, and wherein the adaptive filter is operably updated according to a residual error from the feedback equalizer.
2. The system of claim 1 , wherein the wirelessly transmitted signal is received via an adaptive finite impulse response (FIR) filter.
3. The system of claim 2 , wherein the adaptive FIR filter is operably updated according to the residual error from the feedback equalizer.
4. The system of claim 2 , wherein the adaptive FIR filter is operably updated according to the phase recovery information.
5. The system of claim 1 , wherein the feedback equalizer comprises an adaptive finite impulse response (FIR) filter.
6. The system of claim 5 , wherein the adaptive FIR filter is operably updated according to the residual error from the feedback equalizer.
7. The system of claim 5 , wherein the adaptive FIR filter is operably updated according to the phase recovery information.
8. The system of claim 1 , wherein the adaptive filter in the phase recovery circuit comprises an impulse response (IIR) filter.
9. The system of claim 1 , wherein taps of the impulse response IIR filter are based on taps of a finite impulse response (FIR) filter in the feedback equalizer.
10. The system of claim 1 , wherein the phase recovery information is generated according to a predetermined pilot in the wirelessly transmitted signal.
11. A method comprising:
receiving a wirelessly transmitted signal;
adjusting, using a feedback equalizer, a current symbol in the wirelessly transmitted signal according to phase recovery information; and
generating, using a phase recovery circuit comprising an adaptive filter, the phase recovery information associated with the wirelessly transmitted signal, wherein the adaptive filter is operably updated according to a residual error from the feedback equalizer.
12. The method of claim 11 , wherein the wirelessly transmitted signal is received via an adaptive finite impulse response (FIR) filter.
13. The method of claim 12 , wherein the method comprises updating the adaptive FIR filter according to the residual error from the feedback equalizer.
14. The method of claim 12 , wherein the method comprises updating the adaptive FIR filter according to the phase recovery information.
15. The method of claim 11 , wherein the feedback equalizer comprises an adaptive finite impulse response (FIR) filter.
16. The method of claim 15 , wherein the method comprises updating the adaptive FIR filter according to the residual error from the feedback equalizer.
17. The method of claim 15 , wherein the method comprises updating the adaptive FIR filter according to the phase recovery information.
18. The method of claim 11 , wherein the adaptive filter in the phase recovery circuit comprises an impulse response (IIR) filter.
19. The method of claim 11 , wherein taps of the impulse response IIR filter are based on taps of a finite impulse response (FIR) filter in the feedback equalizer.
20. The method of claim 11 , wherein the method comprises generating the phase recovery information according to a predetermined pilot in the wirelessly transmitted signal.