# STRATOS (Spire GNSS radio occultation receiver)
*sensor . products*

Spire in-house GNSS receiver payload carried on LEMUR small satellites for GNSS radio occultation, precise orbit determination, and related RF Earth observation products. NASA CSDA and WMO OSCAR identify STRATOS as the payload collecting GNSS signals used for atmospheric, ionospheric, and space-weather data products.

## Specifications
- **product status**: operational
- **deployment context**: orbital
- **manufacturer**: spire-global
- **sensor**: {"instrument_family":"radiometer","measurement_principle":"passive","frequency_bands_ghz":[1.17645,1.2276,1.57542],"polarisation_modes":["RHCP"],"scan_type":"static","notes":"STRATOS is a software-defined GNSS receiver/payload. NASA CSDA lists POD and RO antennas using L1/L2 RHCP, while Spire describes multi-frequency L1/L2/L5 and multi-constellation tracking. Frequencies are GPS nominal L5/L2/L1 representatives for the GNSS L-band signals."}
- **entity type**: sensor
- **last verified date**: 2026-06-14
- **verified by**: agency-doc
- **claim status**: agency-sourced
- **provider**: spire-global
- **attributes**: {"kind":"sensor","product_status":"operational","deployment_context":"orbital","manufacturer":"spire-global","description":"Spire in-house GNSS receiver payload carried on LEMUR small satellites for GNSS radio occultation, precise orbit determination, and related RF Earth observation products. NASA CSDA and WMO OSCAR identify STRATOS as the payload collecting GNSS signals used for atmospheric, ionospheric, and space-weather data products.","sensor":"{\"instrument_family\":\"radiometer\",\"measurement_principle\":\"passive\",\"frequency_bands_ghz\":[1.17645,1.2276,1.57542],\"polarisation_modes\":[\"RHCP\"],\"scan_type\":\"static\",\"notes\":\"STRATOS is a software-defined GNSS receiver/payload. NASA CSDA lists POD and RO antennas using L1/L2 RHCP, while Spire describes multi-frequency L1/L2/L5 and multi-constellation tracking. Frequencies are GPS nominal L5/L2/L1 representatives for the GNSS L-band signals.\"}"}
- **relevance**: in-scope

## Editorial
STRATOS is Spire Global's in-house software-defined GNSS receiver payload flown on LEMUR small satellites for GNSS radio occultation, precise orbit determination, and related RF Earth observation products [^nasa-csda-spire][^wmo-oscar-stratos]. It collects GNSS L-band signals for atmospheric, ionospheric, and space-weather data products [^nasa-csda-spire][^spire-earth-intelligence]. The payload uses L1 and L2 RHCP receive antennas and supports multi-frequency L1, L2, and L5 multi-constellation tracking [^nasa-csda-spire][^spire-earth-intelligence]. Representative GPS L5, L2, and L1 center frequencies for those tracked GNSS bands are 1.17645, 1.2276, and 1.57542 GHz [^nasa-csda-spire]. LEMUR is Spire's Low Earth Multi-Use Receiver satellite line, and STRATOS is the payload associated with the GNSS observations used in Spire weather, climate, and space-weather services [^wmo-oscar-lemur][^spire-lemur][^spire-earth-intelligence].

## Compositional position
- spire-lemur-2 (missions) --[mission_payloads]--> STRATOS (Spire GNSS radio occultation receiver)

## Sources
- [nasa-csda-spire] | NASA CSDA vendor page for Spire | https://science.nasa.gov/earth-science/csda/vendor-spire/ | tier=agency-doc | accessed=2026-06-14
- [wmo-oscar-stratos] | WMO OSCAR instrument record for STRATOS | https://space.oscar.wmo.int/instruments/view/stratos | tier=agency-doc | accessed=2026-06-14
- [wmo-oscar-lemur] | WMO OSCAR satellite programme record for Low Earth Multi-Use Receiver | https://space.oscar.wmo.int/satelliteprogrammes/view/lemur | tier=agency-doc | accessed=2026-06-14
- [spire-earth-intelligence] | Spire Advanced Earth Intelligence | https://spire.com/weather-climate/earth-intelligence-data/ | tier=operator-marketing | accessed=2026-06-14
- [spire-lemur] | Spire Low Earth Multi-Use Receiver overview | https://spire.com/spirepedia/low-earth-multi-use-receiver/ | tier=operator-marketing | accessed=2026-06-14

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Source: https://eo-atlas.org/products/sensor/stratos
Maintainer: SpectraWorks B.V. (CC-BY 4.0)