# GPM Microwave Imager
*sensor . products*

Multi-channel conical-scanning microwave radiometer on the GPM Core Observatory for precipitation retrieval and inter-satellite radiometric calibration.

## Specifications
- **product status**: operational
- **deployment context**: orbital
- **manufacturer**: ball-aerospace
- **sensor**: {"instrument_family":"radiometer","measurement_principle":"passive","frequency_bands_ghz":[10.65,18.7,23.8,36.5,89,166,183.31],"polarisation_modes":["H","V"],"scan_type":"conical","scan_rate_rpm":32,"incidence_angle_deg":52.8,"antenna_diameter_m":1.2,"swath_km":885,"notes":"NASA describes 13 microwave channels from 10 to 183 GHz and an 885 km scan swath; WMO lists a 904 km mission instrument swath. Sensor stub uses the NASA instrument page value pending full sensor research."}
- **entity type**: sensor
- **last verified date**: 2026-06-16
- **verified by**: agency-doc
- **claim status**: agency-sourced
- **provider**: ball-aerospace
- **attributes**: {"kind":"sensor","product_status":"operational","deployment_context":"orbital","manufacturer":"ball-aerospace","description":"Multi-channel conical-scanning microwave radiometer on the GPM Core Observatory for precipitation retrieval and inter-satellite radiometric calibration.","sensor":"{\"instrument_family\":\"radiometer\",\"measurement_principle\":\"passive\",\"frequency_bands_ghz\":[10.65,18.7,23.8,36.5,89,166,183.31],\"polarisation_modes\":[\"H\",\"V\"],\"scan_type\":\"conical\",\"scan_rate_rpm\":32,\"incidence_angle_deg\":52.8,\"antenna_diameter_m\":1.2,\"swath_km\":885,\"notes\":\"NASA describes 13 microwave channels from 10 to 183 GHz and an 885 km scan swath; WMO lists a 904 km mission instrument swath. Sensor stub uses the NASA instrument page value pending full sensor research.\"}"}
- **relevance**: in-scope

## Editorial
The GPM Microwave Imager is a conical-scanning passive microwave radiometer on the GPM Core Observatory. It uses 13 channels across 10.65, 18.7, 23.8, 36.5, 89, 166.5, and 183.31 GHz, with horizontal and vertical polarization coverage across the channel set [^nasa-gmi] [^wmo-gmi-core] [^noaa-mirs-gmi]. In the GPM mission, GMI supports near-global precipitation retrieval, frequent revisit, precipitation standard products, and constellation radiometric-standard functions [^nasa-gmi]. Its scan geometry uses a 1.2 m antenna, 32 rpm rotation, and a 52.8 degree Earth-incidence angle [^nasa-gmi] [^wmo-gmi-core]. The scan swath is 885 km by the instrument scan definition [^nasa-gmi]. The useful-swath value is narrower at 850 km [^wmo-gmi-core]. The GMI Core utilization period is 2014-2030 [^wmo-gmi-core].

## Compositional position
- gpm-core-observatory (missions) --[mission_payloads]--> GPM Microwave Imager

## Sources
- [nasa-gmi] | GPM Microwave Imager (GMI), NASA Global Precipitation Measurement Mission | https://gpm.nasa.gov/missions/GPM/GMI | tier=agency-doc | accessed=2026-06-16
- [wmo-gmi-core] | WMO OSCAR instrument record: GMI (core) | https://space.oscar.wmo.int/instruments/view/gmi_core | tier=agency-doc | accessed=2026-06-16
- [noaa-mirs-gmi] | NOAA MiRS GPM Microwave Imager instrument characteristics | https://www.star.nesdis.noaa.gov/mirs/gpmgmi.php | tier=agency-doc | accessed=2026-06-16

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