Method and Apparatus for Performing Frequency Synchronization
AssigneeGlobal Locate, Inc.
InventorsJason GOLDBERG, Charles Abraham, Emre Tapucu
Life of this patent
Estimating the term…
Abstract
A method and apparatus for performing frequency analysis of sub-epoch correlations to estimate an unknown frequency of a received signal is provided. The method includes forming a sequence of correlation values from a plurality of correlations performed over a period less than a repeating period of a code, and analyzing the sequence of correlation values to estimate the frequency that is used to receive a signal comprising the code.
Claims20
A method for frequency estimation of a correlation signal comprising a sequence of correlation values from a plurality of correlations performed over a period less than a repeating period of a code, comprising:
- generating, using the processing device and based on the correlation signal, a first estimate of a frequency error;
- generating, using the processing device and based on the correlation signal, a second estimate of the frequency error based on the first estimate of the frequency error;
- and
- determining, using the processing device and based on the second estimate of the frequency error, a frequency for receiving a signal comprising the code, wherein the determined frequency corresponds to a maximum signal magnitude of the correlation signal or a maximum signal power of the correlation signal.
A receiver comprising:
- a tuner comprising a numerically controlled oscillator (NCO);
- a signal convolution processor, coupled to the tuner, configured to produce a sequence of correlation values, where the sequence of correlation values are produced over a period less than a repeating period of a code;
- a correlation history memory, coupled to the convolution processor, configured to store the sequence of correlation values;
- and
- a processor coupled to the correlation history memory, wherein the processor is configured to:
- generate, based on the correlation values, a first estimate of a frequency error,
- generate, based on the correlation values, a second estimate of the frequency error based on the first estimate of the frequency error, and
- determine, based on the second estimate of the frequency error, a frequency for receiving a signal comprising the code, wherein the determined frequency corresponds to a maximum signal magnitude of the correlation values or a maximum signal power of the correlation values.
Dependencies are inferred from the claim text.