Shared GNSS Vocabulary

Use this page when a term appears in more than one package and you need to know which meaning is shared. Core owns the vocabulary exchanged between packages; it does not own every algorithm or workflow that uses those words.

Find The Meaning You Need

flowchart TD
    question["reader question"]
    meaning{"what kind of meaning?"}
    identity["identity and signal designation"]
    time["time and sample trace"]
    units["units, frames, and conventions"]
    stage["acquisition, tracking, and observations"]
    nav["navigation outcome"]
    evidence["artifact, diagnostic, and support records"]

    question --> meaning
    meaning --> identity
    meaning --> time
    meaning --> units
    meaning --> stage
    meaning --> nav
    meaning --> evidence

reader question	shared vocabulary	continue with
Which constellation, satellite, signal, band, code, component, slot, or GLONASS channel is this?	Constellation, SatId, SigId, SignalBand, SignalCode, component specifications, and frequency-channel types	Identity contracts
When did this value occur, and is the timestamp based on GPS, UTC, TAI, an epoch, or a receiver sample?	GpsTime, UtcTime, TaiTime, Epoch, SampleClock, and ReceiverSampleTrace	Time contracts
What physical quantity, sign, or coordinate frame does this number use?	meters, seconds, hertz, chips, cycles, WGS-84, ECEF, ENU, and LLH	Unit contracts, coordinate contracts, and engineering conventions
What evidence crossed the acquisition, tracking, or observation boundary?	requests, hypotheses, results, tracking epochs, transitions, observation epochs, uncertainty, quality, and differencing records	Observation and tracking contracts
What did navigation produce without exposing solver internals?	solution status, validity, lifecycle, residuals, inter-system bias, uncertainty, refusal, and position fields	Navigation result contracts
How is evidence versioned, diagnosed, validated, or declared supported?	artifact envelopes, payload kinds, diagnostic events, validation reports, and support rows	Artifact contracts and configuration and diagnostics

The contract map is the complete ownership index. Source links identify where meaning is defined; public consumers import supported items through bijux_gnss_core::api.

Similar Words That Are Not Interchangeable

PRN, Satellite, Signal, And Channel

A PRN number alone is not a globally unique satellite identity. SatId combines constellation and PRN. SigId adds band and code. GLONASS L1 FDMA also needs a frequency channel. Preserve the most specific identity available when records cross package or artifact boundaries.

Epoch, Receiver Time, And Transmit Time

An epoch index orders processing but does not establish physical time. ReceiverSampleTrace ties receiver time to sample index and sample rate. Transmit time describes the signal path and must not be substituted for receive time. State the time system whenever a plain scalar could be ambiguous.

Carrier Frequency, Doppler, And Carrier Phase

Hertz can describe an absolute carrier, an intermediate-frequency-relative carrier estimate, or Doppler. Cycles describe phase, not frequency. A field needs a name and convention that distinguishes these meanings; sharing a unit does not make them equivalent.

Status, Validity, Lifecycle, And Refusal

Status describes the classified outcome, validity says whether consumers may use it under the contract, lifecycle locates it in processing history, and refusal explains why a usable result was not produced. Do not collapse these records into one boolean.

Artifact Validity And Scientific Accuracy

Artifact validation proves schema and cross-field coherence. It does not prove that acquisition locked the correct peak, tracking remained physically accurate, or navigation converged to truth. Those claims remain with the receiver or navigation evidence.

Leave Core At The Behavior Boundary

flowchart LR
    core["shared meaning"]
    signal["signal generation and DSP"]
    receiver["stage execution and channel state"]
    nav["models, corrections, and estimation"]
    infra["datasets, persistence, and inspection"]
    command["operator workflow and presentation"]

    core --> signal
    core --> receiver
    core --> nav
    core --> infra
    core --> command

• For code generation, sampling, spectra, replicas, or loop mathematics, follow the signal handbook.
• For acquisition decisions, tracking lifecycle, observation construction, or runtime artifacts, follow the receiver handbook.
• For orbit products, corrections, position estimation, PPP, RTK, or integrity, follow the navigation handbook.
• For registry interpretation, run layout, persistence, or artifact inspection, follow the infrastructure handbook.
• For command behavior and rendered output, follow the operator handbook.

Adding Shared Language

A proposed term belongs in core only when producers and consumers need the same meaning independently of their implementations. Before adding it:

1. name at least two package roles that exchange it;
2. define units, identity, frame, time system, validity, and failure semantics;
3. distinguish the record from the behavior that creates it;
4. decide whether serialization or versioning is part of the promise;
5. add evidence for exact meaning and invalid states;
6. avoid a synonym when an existing contract can be extended without ambiguity.

The ownership boundary resolves placement disputes, and the shared concepts guide connects records to their behavior owners.