Timing pilot generation for highly-spectrally-efficient communications
Methods and systems are provided for timing synchronization for reception of highly-spectrally efficient communications. An example method may include, mapping, in a transmitter, a plurality of transmit bits to a plurality of symbols at a symbol rate that is based on an oscillator signal. The plurality of symbols may be processed via a filter. The processing may result in an inter-symbol correlated (ISC) signal. The oscillator signal may be frequency divided to generate one or more pilot signals having a frequency that is a sub-harmonic of a frequency of the oscillator signal. The pilot signal may be injected into the ISC signal. The injecting may result in an ISC signal with timing carrier. The ISC signal with timing carrier may be transmitted. Gain of the one or more pilot signals may be adjusted based on a spectral mask value associated with the transmitting.
1. A receiver comprising:
front-end circuitry operable to receive a signal via a channel;
performance measurement circuitry operable to measure a performance indicator for said received signal; and
timing recovery circuitry operable to:
determine, based on said measured performance indicator, a divider ratio used for generation of a timing pilot in said received signal; and
process said received signal using said determined divider ratio.
2. The receiver of claim 1 , wherein said determination of said divider ratio comprises adjustment of said divider ratio in response to said measured performance indicator being above a determined threshold.
3. The receiver of claim 1 , wherein said determination of said divider ratio comprises adjustment of said divider ratio in response to said measured performance indicator being below a determined threshold.
4. The receiver of claim 1 , wherein said timing recovery circuitry is operable to determine said divider ratio based on a spectral mask that is applicable to said received signal.
5. The receiver of claim 1 , wherein said receiver is operable to output said measured performance indicator for transmission to a transmitter from which said received signal originated.
6. The receiver of claim 1 , wherein said timing recovery circuitry is operable to determine said divider ratio based on information obtained during pairing with a transmitter from which said received signal originated.
7. The receiver of claim 1 , wherein said divider ratio is stored in a look-up table indexed by values of said performance indicator.
8. The receiver of claim 1 , wherein said timing recovery circuitry is operable to use said determined divider ratio to cancel said timing pilot in said received signal.
9. The receiver of claim 1 , wherein said measured performance indicator is symbol error rate.
10. The receiver of claim 1 , wherein said measured performance indicator is bit error rate.
11. A method comprising:
receiving, via front-end circuitry of a receiver, a signal via a channel;
measuring, via performance measurement circuitry of said receiver, a performance indicator for said received signal;
determining, by timing recovery circuitry of said receiver based on said measured performance indicator, a divider ratio used for generation of a timing pilot in said received signal; and
processing, by said timing recovery circuitry, said received signal using said determined divider ratio.
12. The method of claim 11 , wherein said determining said divider ratio comprises adjusting said divider ratio in response to said measured performance indicator being above a determined threshold.
13. The method of claim 11 , wherein said determining said divider ratio comprises adjusting said divider ratio in response to said measured performance indicator being below a determined threshold.
14. The method of claim 11 , comprising determining, by said timing recovery circuitry, said divider ratio based on a spectral mask that is applicable to said received signal.
15. The method of claim 11 , comprising outputting, by said receiver, said measured performance indicator for transmission to a transmitter from which said received signal originated.
16. The method of claim 11 , comprising determining, by said timing recovery circuitry, said divider ratio based on information obtained during pairing with a transmitter from which said received signal originated.
17. The method of claim 11 , comprising storing said divider ratio in a look-up table indexed by values of said performance indicator.
18. The method of claim 11 , comprising cancelling said timing pilot in said received signal using said determined divider ratio.
19. The method of claim 11 , wherein said measured performance indicator is symbol error rate.
20. The method of claim 11 , wherein said measured performance indicator is bit error rate.