Module signal 

GPS L1 C/A code generation, coherent correlation, and acquisition.

The functions here are deterministic time-domain signal primitives. They intentionally keep the same simple operation order as the original Sidereon implementation: C/A chips are generated by clocking the two IS-GPS-200 LFSRs, sampled by zero-order hold, and correlation/acquisition are direct nested sums over samples and Doppler bins.

Structs

AcquisitionGrid

Acquisition-grid metadata.

AcquisitionOptions

Options for acquire.

AcquisitionResult

Result of a 2D code-phase/Doppler acquisition search.

CorrelateOptions

Options for correlate.

CorrelationResult

Coherent correlation result.

IqSample

One complex baseband sample.

ReplicaOptions

Options for replica.

Enums

SignalError

Error returned by GPS C/A signal helpers.

Constants

CA_CHIP_RATE_HZ

GPS C/A chipping rate in chips per second.

CA_CODE_LENGTH

GPS C/A code length in chips.

Functions

acquire

Acquire a PRN by direct 2D code-phase/Doppler search.

autocorrelation

Circular autocorrelation over all lags.

ca_chip

Return one bipolar chip at a wrapping zero-based index.

ca_code

Return the 1023 bipolar (+1/-1) GPS C/A chips for a PRN.

coherent_loss

Coherent integration loss from residual frequency error.

coherent_loss_db

Coherent integration loss in decibels.

correlate

Coherently correlate a sample record against a PRN replica.

correlate_against

Coherent correlation against an explicit sampled code.

correlation_at

Single-lag circular correlation.

cross_correlation

Circular cross-correlation over all lags.

replica

Build a sampled C/A-code replica.

snr_post_db

Post-correlation predetection SNR in dB.