Orbis.GNSS.QC (Orbis v0.31.0)

Measurement-quality control for single-point positioning.

The numerical modeling and FDE orchestration live in the astrodynamics-gnss Rust core. This module keeps the Elixir API shape, normalizes options and epochs for the NIF, maps errors, and decodes the unchanged public result maps.

Summary

Types

raim_result()

The result of raim/2.

weight_entry()

A {satellite_id, elevation_deg} or {satellite_id, elevation_deg, cn0_dbhz} entry.

Functions

chi2_inv(p, k)

Chi-square inverse CDF (quantile).

fde(source, observations, epoch, opts \\ [])

Fault detection and exclusion: solve, run RAIM, exclude the worst satellite, and repeat until the measurement set is self-consistent or the exclusion budget is exhausted.

pseudorange_variance(elevation_deg, opts \\ [])

Pseudorange measurement variance (m^2) from satellite elevation.

raim(solution, opts \\ [])

Residual-based RAIM: a chi-square goodness-of-fit test on a positioning solution.

sigmas(entries, opts \\ [])

Build a satellite => sigma_m map for a list of weight entries.

weight_vector(entries, opts \\ [])

Build a satellite => inverse_variance_weight map for a list of weight entries.

Types

raim_result()

@type raim_result() :: %{
  fault_detected?: boolean(),
  test_statistic: float(),
  threshold: float() | nil,
  dof: integer(),
  testable?: boolean(),
  normalized_residuals: %{required(String.t()) => float()},
  worst_sat: String.t() | nil
}

The result of raim/2.

weight_entry()

@type weight_entry() :: {String.t(), number()} | {String.t(), number(), number()}

A {satellite_id, elevation_deg} or {satellite_id, elevation_deg, cn0_dbhz} entry.

Functions

chi2_inv(p, k)

@spec chi2_inv(float(), pos_integer()) :: float()

Chi-square inverse CDF (quantile).

fde(source, observations, epoch, opts \\ [])

@spec fde(
  term(),
  [Orbis.GNSS.Positioning.observation()],
  Orbis.GNSS.Positioning.epoch(),
  keyword()
) ::
  {:ok,
   %{
     solution: Orbis.GNSS.Positioning.Solution.t(),
     excluded: [{String.t(), :raim_excluded}],
     iterations: non_neg_integer()
   }}
  | {:error, {:fault_unresolved, float()}}
  | {:error, term()}

Fault detection and exclusion: solve, run RAIM, exclude the worst satellite, and repeat until the measurement set is self-consistent or the exclusion budget is exhausted.

pseudorange_variance(elevation_deg, opts \\ [])

@spec pseudorange_variance(
  number(),
  keyword()
) :: float() | {:error, :invalid_elevation | :missing_cn0}

Pseudorange measurement variance (m^2) from satellite elevation.

Returns a float, {:error, :invalid_elevation} for elevations at or below the horizon, or {:error, :missing_cn0} when model: :elevation_cn0 is selected without :cn0.

raim(solution, opts \\ [])

@spec raim(
  Orbis.GNSS.Positioning.Solution.t(),
  keyword()
) :: raim_result()

Residual-based RAIM: a chi-square goodness-of-fit test on a positioning solution.

sigmas(entries, opts \\ [])

@spec sigmas(
  [weight_entry()],
  keyword()
) :: %{required(String.t()) => float()}

Build a satellite => sigma_m map for a list of weight entries.

weight_vector(entries, opts \\ [])

@spec weight_vector(
  [weight_entry()],
  keyword()
) :: %{required(String.t()) => float()}

Build a satellite => inverse_variance_weight map for a list of weight entries.