Kshana is an open-source simulator for PNT (positioning, navigation and timing) resilience. Replay jamming, spoofing and clock holdover when GNSS (Global Navigation Satellite System) signals fail, in a Rust engine that runs right in your browser, and see exactly which results were checked against independent references.
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Kshana ProSame engine, amplified: 608 designs, one Pareto frontCampaign: Engine v0.29.0, build e6bde8f · campaign-jam-spoof-holdover-integrity.toml · seed 20260928Open in Kshana StudioReportJSONTOML
Orbits: Engine v0.29.0, build e6bde8f · constellation-multi-gnss-coverage.toml · deterministic, no seedOpen in Kshana StudioReportJSONTOML
The console, the three cards and the log replay one chained run of 6 phases and 18 member runs on its 10 s grid (T+01:16:10 of mission time). The orbits are the 102 satellites of GPS, Galileo, BeiDou and GLONASS from the constellation run, each recovered as a circular two-body orbit from the engine's ground track (worst residual 0.0034°), radii compressed for display. Links are drawn to satellites above the constellation run's 10° mask (25° in the integrity-alarm phase, the campaign's reacquisition mask), dimmed by its jamming and cut in holdover. Earth: NASA Blue Marble and Black Marble. Kshana Studio replays the chained run in your browser; the engine's own report and the command reproduce each run.
The GNSS L band as one PSD (power spectral density): frequency across, time down, colour for power above the noise floor. The signals sit under that floor, so what lights up is the jammers: a chirp, a CW (continuous-wave) tone and narrowband noise. Hover, tap or use the arrow keys for each band's C/N0 (carrier-to-noise density) and J/S (jammer-to-signal ratio).
The waterfall is drawn from the recorded run with JavaScript. The engine's report below shows the same run.
Engine run of l-band-waterfall-jamming.tomlOpen in Kshana StudioEngine report
Spectrum runScenario fileResult data
Campaign it drives: campaign-spectrum-holdover-integrity.tomlOpen in Kshana StudioEngine reportScenario file
Modelled: closed-form spectra over a thermal noise floor, scored per band by spectral separation; jammer powers and timings are scenario inputs. The time axis counts seconds before now; the cyan line marks where the replay restarted. Kshana Studio runs the same scenario in your browser and replays the waterfall; the report and the command reproduce the run.
Every satellite is tracked. The clock is disciplined to GNSS time, and the protection level sits well below the alert limit.
clockseed 42jammingseed 1integrityseed 7clockseed 43jammingseed 1integrityseed 7spoofspoof-detectjammingseed 1clockseed 44gnss-insseed 7jammingseed 1clockseed 45jammingseed 1integrityseed 7clockseed 46jammingseed 1integrityseed 7Engine v0.29.0, build e6bde8f · campaign-jam-spoof-holdover-integrity.toml · seed 20260928Open in Kshana StudioReportJSONTOML
From the first jammed satellite to the last nanosecond of clock holdover: signals, sensors, clocks, orbits and integrity in one simulator. Every picture below is a real engine run, and says which.
A broadband jammer on a mast and a receiver moved over a grid around it: every cell is its own run of the engine's jamming kind. Shade is the mean J/S (jammer-to-signal ratio); red cells lost every satellite.
Engine v0.29.0 · maritime-strait-jamming.toml · seed 1 · receiver moved per cellOpen in Kshana StudioEvery cell, on Missions
A spoofer captures the receiver and walks its time off at a steady rate. Each clock's integrity monitor has its own detection bound: the quantum clock flags the lie almost at once, the classical one only once the offset has grown.
spoof-attack.toml · deterministic, no seedOpen in Kshana StudioReportFrom the moment GNSS disappears: the median and 95th percentile of 200 Monte Carlo runs for a chip-scale atomic clock (CSAC) and an optical lattice clock, and the one-day error of four more classes: an optical master clock, a hydrogen maser, a rubidium atomic frequency standard (RAFS) and its miniature version (mini-RAFS).
clock-ensemble.toml · seed 42Open in Kshana StudioReportOne-day column: Engine v0.29.0 · lunar-time-budget.toml · deterministic, no seedOpen in Kshana StudioReport
When GNSS drops, the INS (inertial navigation system) carries on and its error cone opens. Two inertial measurement units (IMUs), one budget.
small-uas-jammed-nav.toml · seed 7Open in Kshana StudioReportHow long a clock stays inside its guard interval after the last fix: the question time-slotted networks care about.
slot-timing-ocxo-leo.toml · deterministic, no seedOpen in Kshana StudioReportProtection levels (PL) from receiver autonomous integrity monitoring (RAIM) and its advanced form (ARAIM), checked against the alert limit: here, the chained mission's integrity-alarm phase. Hatched bars are epochs where no protection level could be formed.
Engine v0.29.0, build e6bde8f · campaign-jam-spoof-holdover-integrity.toml · seed 20260928Open in Kshana StudioReportJSONTOML
MTIE (maximum time interval error) and TDEV (time deviation) of a 24-hour holdover against ITU-T (International Telecommunication Union, Telecommunication Standardization Sector) limits, here the PRTC-A (primary reference time clock, class A) one.
telecom-prtc-holdover-24h.toml · seed 20260925Open in Kshana StudioReportSGP4 (Simplified General Perturbations 4) propagation of a real two-line element set, drawn on real imagery; CCSDS OEM and SP3 ephemerides in and out.
ephemeris.toml · deterministic, no seedOpen in Kshana StudioReportPositioning, navigation and timing around the Moon: horizontal and vertical protection levels (HPL, VPL) from ARAIM on a lunar navigation service.
lunanet-araim.toml · deterministic, no seedOpen in Kshana StudioReportWeigh a quantum clock against a classical one before anyone buys hardware: holdover across a sweep of the classical clock's noise.
sweep-clock-stability.toml · seed 42Open in Kshana StudioReportThe same Rust engine ships as WebAssembly for Kshana Studio, a CLI (command-line interface), Python and JavaScript packages, a JetBrains Marketplace plugin for your IDE (integrated development environment) and an MCP (Model Context Protocol) server.
CCSDS OEM: Consultative Committee for Space Data Systems Orbit Ephemeris Message. SP3: Standard Product 3 orbit format.
Knowing the edges matters as much as the features.
Your AI (artificial intelligence) assistant runs the engine over MCP (Model Context Protocol) through kshana-mcp and reads back JSON (JavaScript Object Notation).
For anyone, nothing to install.
The engine runs locally as WebAssembly; nothing is uploaded.
For engineers who want the kshana command.
Then check itkshana --version
For analysts and notebooks.
Then check itpython -c "import kshana; print(kshana.version())"
For anyone using an MCP-capable assistant.
Then check itcargo install --list | grep kshana-mcp
Then register it in your assistant's MCP client configuration. Full configuration on Developers
The recorded session plays here step by step.
Same run in the Studio: Engine v0.29.0 · clock-holdover.toml · seed 42Open in Kshana StudioReport
One receiver, T+01:16:10 of mission time: a clean sky, a jammer, a spoofer that moves the answer instead of blocking it, then a clock left on its own. The 102 satellites are the four systems of the constellation run, on the real Earth. Scroll.
8 satellites tracked at a mean C/N0 (carrier-to-noise density) of 43.0 dB-Hz. The vertical protection level stays between 9.1 and 21.6 m, under the 50 m alert limit.
A broadband jammer 1.0 km away comes on at -30 dBW. C/N0 falls to 27.7 dB-Hz, just above the 25 dB-Hz tracking floor. Loud, so the receiver knows.
A spoofer pushes the clock at 0.1 ns/s. The RF (radio-frequency) detector alarms at T+00:20:00; the clock-aided monitor needs 370 s, and by then 36.0 ns are already pulled in.
The jammer goes to 10 dBW and every satellite is lost. The clock free-runs from the 37.0 ns the spoofer left and crosses its 50 ns guard at T+00:35:40; the inertial error reaches 24.3 km.
Campaign: Engine v0.29.0, build e6bde8f · campaign-jam-spoof-holdover-integrity.toml · seed 20260928Open in Kshana StudioReportJSONTOML
Orbits: Engine v0.29.0, build e6bde8f · constellation-multi-gnss-coverage.toml · deterministic, no seedOpen in Kshana StudioReportJSONTOML
Kshana Pro is a proprietary overlay that depends on the open core and never forks it, available under contract. No prices on a web page: every paid route starts with a message to contact@ashforde.org.
608 designs, all run: the Pareto front and its knee
Uncertainty and sensitivity2,000 runs: a confidence band against a limit
Mission dossier12 requirements checked against real runs, 21-page PDF (Portable Document Format)