Signal quality monitor
AssigneeNXP B.V.
InventorStefan Drude
Life of this patent
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Abstract
Various embodiments relate to a method of determining the presence of a spread spectrum signal, including: receiving N input samples of a signal; performing a first autocorrelation on the N input samples with a first offset; performing a second autocorrelation on the N input samples with a second offset; performing a third autocorrelation on the N input samples with a third offset; performing a fourth autocorrelation on the N input samples with a fourth offset; performing a fifth autocorrelation on the N input samples with a fifth offset; determining if the values of the first, second, and third autocorrelations are decreasing, and determining if the values of the fourth and fifth autocorrelations are less than a threshold value, then determining that a spread spectrum signal is present in the N input samples.
Claims20
A method of determining a presence of a spread spectrum signal, comprising:
- receiving N input samples of a signal;
- performing a first autocorrelation on the N input samples with a first offset;
- performing a second autocorrelation on the N input samples with a second offset;
- performing a third autocorrelation on the N input samples with a third offset;
- performing a fourth autocorrelation on the N input samples with a fourth offset;
- performing a fifth autocorrelation on the N input samples with a fifth offset;
- determining if values of the first, second, and third autocorrelations are decreasing;
- determining if values of the fourth and fifth autocorrelations are less than a threshold value;
- and
- determining that the spread spectrum signal is present in the N input samples when both the values of the first, second, and third autocorrelations are decreasing and the values of the fourth and fifth autocorrelations are less than the threshold value.
A system that determines a presence of a spread spectrum signal, comprising:
- M-1 delay lines configured to receive input samples to produce M-1 delayed input samples;
- M multipliers with an output, wherein the M multipliers are configured to receive an input sample as a first input, a first multiplier is configured to receive the input sample as a second input, and subsequent multipliers are each configured to receive a delayed input sample from each of the M-1 delay lines;
- M accumulators, each accumulator configured to accumulate respective outputs of one of the M multipliers;
- a signal presence determiner coupled to the M accumulators, configured to determine the presence of the spread spectrum signal based upon the outputs of the M accumulators identifying both mainlobe and sidelobe regions of an autocorrelation function of the spread spectrum signal.
Dependencies are inferred from the claim text.