# osqzss/gps-sdr-sim

Software-Defined GPS Signal Simulator

Repository: https://github.com/osqzss/gps-sdr-sim
Canonical: https://ross.abutalabs.com/products/gps-sdr-sim
Language: C
License: MIT
License Family: permissive
Archived: true
Last push: 2025-01-26T22:54:32+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 3, release rhythm 35, longevity 100
- inputs: {"age_days": 4098, "days_push": 584, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, archived
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3461, forks 977 (observed 2026-08-28T04:08:05.654373+00:00)

## What it is
A C-based software-defined GPS signal simulator that generates GPS baseband I/Q sample streams from user-defined trajectories and broadcast ephemeris data. The output can be transmitted as RF signals via SDR platforms such as HackRF, bladeRF, USRP, and ADALM-Pluto.

## Use cases
- simulate GPS signals for testing GNSS receivers
- generate GPS RF signals from a custom trajectory
- spoof GPS signals with an SDR like HackRF
- test GPS receiver behavior with synthetic satellite signals
- replay GPS signals for hardware-in-the-loop testing
- create GPS baseband data from NMEA or ECEF motion files

## When to choose
- you need to generate realistic GPS L1 signals for receiver testing
- you own a supported SDR (HackRF, bladeRF, USRP, ADALM-Pluto) and want to transmit GPS signals
- you need reproducible GPS signal scenarios from ephemeris and motion data

## When to avoid
- you need real-time GPS signal generation rather than pre-generated sample files
- you need other GNSS constellations like Galileo or BeiDou
- you want a GUI-based simulator rather than a command-line tool

## Facets
- artifact type: cli-tool
- maturity: active
- function: simulation, cli
- domain: hardware, security, embedded-systems
- platform: windows, cli, cpp
- tags: gps, gnss, sdr, signal-simulator, hackrf, bladerf, usrp, adalm-pluto, rf, signal-processing, linux, macos

## Member repositories
- osqzss/gps-sdr-sim (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:05.654373+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:36:55.637543+00:00, confidence not recorded.
  - readme: https://github.com/osqzss/gps-sdr-sim (fetched 2026-08-28T04:08:05.654373+00:00, sha 08268424eb09)
- Data as of 2026-08-30T08:39:29.467469+00:00.