# How to read a GNSS jamming and spoofing map A GNSS map helps you explore where navigation observations change, when they change and which evidence supports an interpretation. SatellAItes brings reception indicators, satellite geometry and environmental context into one workspace. Start with the source and observation time: a coloured cell is a summary of available information, not an automatic diagnosis of a transmitter or a guarantee of reception. Canonical: https://satellaites.com/en/gnss-jamming-spoofing-guide/ Language: en Reviewed: 2026-10-30 ## Jamming, spoofing and what the map can establish Jamming disrupts the reception of useful radio signals; spoofing attempts to make a receiver accept misleading signals or information. A map labelled “jamming and spoofing” still needs evidence to distinguish these mechanisms. Low reported navigation quality alone cannot confirm either one, identify the responsible actor or locate a transmitter. Aircraft ADS-B observations can include Navigation Integrity Category (NIC) and Navigation Accuracy Category for Position (NACp). These describe different aspects of the reported navigation solution and must not be treated as interchangeable measurements of radio interference. Open a cell, read its source, sample information, observation interval and explanation, then compare nearby observations. A single unusual aircraft report deserves more caution than a consistent pattern supported by independent evidence. - [Flightradar24 — ADS-B and NIC methodology](https://www.flightradar24.com/blog/inside-flightradar24/gps-jamming-map/) - [GPSJAM — interpretation and limitations](https://gpsjam.org/faq) ## Coverage, observation dates and UTC An empty area does not demonstrate that GNSS reception is good. It may mean that no suitable observation reached the service, that coverage is sparse or that the selected period contains insufficient information. Similarly, a historical event is not necessarily still active. Always distinguish the time of an observation from the time the page was opened or a file downloaded. Use UTC to compare reports across countries and midnight boundaries. Keep the start and end of the selected interval with every screenshot or export. Before comparing two dates, check that the sources and coverage are comparable; a change in the number of observations can alter the picture without proving a change in interference. - [GPSJAM — coverage and daily UTC aggregation](https://gpsjam.org/faq) - [SatellAItes — map, sources and selected period](https://satellaites.com/en/gnss-reception-map/) ## GPS, GLONASS, Galileo and BeiDou GNSS is the collective name for global navigation satellite systems. GPS, GLONASS, Galileo and BeiDou are separate constellations providing positioning, navigation and timing signals. Their names are not synonyms for a single receiver, frequency or observation source. A receiver may use several constellations, while a public aircraft report may not identify which constellation contributed to its solution. Use satellite layers to understand the geometric context at a location and time. An orbit or a satellite above the horizon does not demonstrate that a particular antenna received a usable signal. Buildings, terrain, local interference, receiver configuration and signal processing matter. Keep geometric availability separate from measured signal quality and from a confirmed interference event. - [FAA — global navigation satellite systems](https://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/gps/howitworks) - [GPS.gov — factors affecting GPS accuracy](https://www.gps.gov/gps-accuracy) ## How Starlink and Iridium differ from GNSS Not every satellite constellation is a GNSS constellation. Starlink provides satellite Internet connectivity. Iridium provides satellite communications and also offers positioning, navigation and timing services. Iridium PNT, including the Satellite Time and Location heritage, is relevant to alternative timing and resilience, but should not be confused with GPS or Galileo. Seeing a Starlink or Iridium orbit on the globe does not measure communications availability, validate a subscription or establish the performance of a PNT receiver. For an operational comparison, identify the actual service, compatible equipment, intended use and provider documentation. SatellAItes satellite context can help frame that investigation; it does not certify the reception or resilience of those services. - [Starlink — satellite Internet service](https://starlink.com/pr/map) - [Iridium — PNT services](https://www.iridium.com/iridium-pnt) ## UTC, time and frequency, and synchronisation GNSS supports timing as well as navigation. A timing receiver uses satellite signals and corrections to estimate a time reference; a disciplined oscillator can then support local synchronisation. Telecommunications, power networks and other systems may depend on this chain. Losing or corrupting a reference can matter even when no moving position is being displayed. UTC, a constellation’s system time and a laboratory realisation such as UTC(k) are related but distinct concepts. Traceability and uncertainty depend on equipment, calibration and the complete transfer chain. The UTC dates shown by SatellAItes help align observations; they are not a calibrated time-transfer service, a frequency standard or a certificate of synchronisation accuracy. - [NIST — one-way GNSS time transfer](https://www.nist.gov/pml/time-and-frequency-division/time-services/one-way-gnss-time-transfer) - [EUSPA — GNSS timing and synchronisation](https://www.euspa.europa.eu/gnss-timing-and-synchronisation) ## A reproducible analysis with SatellAItes Begin with a question, a place and a UTC interval. Open the map, select the relevant layers and inspect the available observations. Record source status and coverage before interpreting a colour or comparing locations. Use the satellite and environmental layers as context, rather than treating coincident weather or geometry as proof of a cause. In the analysis workspace, compare the available records and retain the evidence behind your interpretation. When exporting a report, image or data, include the selected period, source attribution, filters and limitations. Separate what was observed from what remains a hypothesis. For a consequential operational decision, corroborate the result with appropriate receiver measurements and authoritative notices; this exploratory map is not a certified navigation service. - [SatellAItes — map and analysis workspace](https://satellaites.com/en/gnss-reception-map/) - [SatellAItes — services and methodology](https://satellaites.com/en/) [SatellAItes map](https://satellaites.com/en/gnss-reception-map/)