RF Safety and Regulatory Spectrum Regulation Informational

What are the coordination requirements for operating a satellite ground station in the US?

Operating a satellite ground station (earth station) in the US requires FCC licensing under Part 25 (Satellite Communications) with frequency coordination to protect existing services. Key requirements: (1) License application: file FCC Form 312 with technical data including antenna gain pattern, transmit power, emission parameters, and site coordinates. (2) Frequency coordination: before filing, the applicant must coordinate with existing licensees through a frequency coordination firm (Comsearch, NSMA, RPC Telecommunications). The coordinator identifies potential interference with terrestrial microwave links (Part 101), other satellite earth stations (Part 25), and federal government systems (NTIA coordination for bands shared with federal services). The coordination report documents the analysis and any agreements reached with affected parties. (3) EMF compliance: earth stations with EIRP exceeding categorical exclusion limits must evaluate RF exposure per FCC OET-65. (4) FAA notification: if the antenna structure exceeds 200 feet (61 m) AGL or is within the approach path of an airport, FAA Form 7460-1 must be filed. (5) ITU coordination: for internationally coordinated satellite bands, the earth station may need to be included in the satellite network filing at the ITU under Article 9. Common earth station bands: C-band (3.7-4.2 GHz receive, 5.925-6.425 GHz transmit), Ku-band (11.7-12.2 GHz receive, 14.0-14.5 GHz transmit), Ka-band (17.7-20.2 GHz receive, 27.5-30.0 GHz transmit), V-band (37.5-42.0 GHz receive, 47.2-50.2 GHz transmit).

Category: RF Safety and Regulatory

Updated: April 2026

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Satellite Earth Station Licensing and Coordination

Satellite ground stations operate in shared frequency bands where coordination with terrestrial services and adjacent satellite systems is essential to prevent harmful interference. The regulatory and coordination process is more complex than terrestrial licensing due to the international nature of satellite communications.

Frequency Coordination Process

The coordination study evaluates potential interference paths: (1) Earth-station-to-terrestrial: the earth station transmitter may interfere with terrestrial microwave receivers. The coordinator calculates the received signal level at each potentially affected terrestrial receiver based on earth station transmit power, antenna off-axis gain toward the terrestrial station, terrain profile, and propagation model (ITU-R P.452 for detailed analysis). Interference is considered harmful if the unwanted signal exceeds the terrestrial receiver's interference threshold (typically -10 dB below the thermal noise floor or a specific I/N ratio). (2) Terrestrial-to-earth-station: terrestrial transmitters may interfere with the earth station receiver. The coordinator identifies terrrestrial transmitters within the coordination contour (ITU-R RR Appendix 7 methodology) and evaluates their potential to exceed the earth station's interference threshold. The coordination distance for a C-band earth station (3.7-4.2 GHz receive) typically extends 200-300 km for line-of-sight and ducting paths.

Earth Station Siting

Earth station location significantly affects coordination complexity and interference susceptibility: (1) Urban sites have more terrestrial microwave links to coordinate with, but larger building-shielding effects. (2) Rural sites have fewer coordination partners but potentially longer interference paths due to terrain. (3) VSAT (Very Small Aperture Terminal) networks with many small earth stations (1-2.4m antennas) often operate under blanket licensing (FCC Part 25.115(c)), which allows multiple stations under a single license with standardized technical parameters, eliminating individual coordination for each antenna. (4) For Ka-band and V-band earth stations, rain attenuation is the primary design driver (8 dB fade margin at Ka-band for 99.5% availability in temperate climates), and site diversity (two earth stations separated by 15-30 km) provides improved availability by exploiting the spatial decorrelation of rain events.

Special Considerations

(1) C-band transition: the 3.7-3.98 GHz band is being repurposed for 5G (FCC 20-22 Order). Existing C-band receive earth stations must either accept interference from 5G stations, install filters to reject 5G signals, or migrate to alternative bands. Incumbent earth stations that registered by a deadline are eligible for transition funding. (2) Non-geostationary satellite constellations (Starlink, OneWeb, Kuiper): NGSO earth stations must coordinate with GSO earth stations to protect the primary GSO service from aggregate NGSO interference. NGSO systems implement avoidance algorithms (e.g., Starlink ceases transmission within a specified angle of GSO satellites). (3) Gateway earth stations (connecting satellite constellations to the internet backbone) require high-availability links with aggressive rain fade margins and typically use Ka-band (larger allocation) or Q/V-band (50/40 GHz, future standard for feeder links).

Common Questions

Frequently Asked Questions

How long does the earth station licensing process take?

For a standard earth station (individual FCC Part 25 license): frequency coordination study: 30-60 days. FCC application preparation: 1-2 weeks. FCC processing time: 60-90 days for routine applications, longer for contested or complex cases. Total: 4-6 months from start to license grant. For VSAT blanket licenses: faster processing since individual site coordination is not required (30-60 days). For emergency or temporary earth stations: Special Temporary Authority (STA) can be granted in 1-10 days for urgent situations. Expedited processing is available through some TCBs for additional fees.

Do receive-only earth stations need a license?

Receive-only earth stations (TVROs, DTH satellite dishes) generally do NOT require an FCC license. However, they also do not receive interference protection: if a new terrestrial service causes interference, the receive-only earth station has no regulatory recourse. Licensees who want interference protection for their receive-only earth stations can register them voluntarily under Part 25.131 (certain C-band and Ku-band receive stations), which provides a degree of coordination protection but not full licensed status. After the C-band transition, registered C-band receive earth stations were eligible for reimbursement of filter and equipment costs.

What is the coordination contour?

The coordination contour is a geographic boundary around an earth station within which terrestrial stations must be coordinated before operational authorization. It is calculated based on the earth station antenna parameters, minimum elevation angle, frequency band, and propagation assumptions per ITU-R RR Appendix 7. Typical contours: C-band (4 GHz): 200-350 km radius depending on terrain. Ku-band (12 GHz): 100-200 km radius. Ka-band (20/30 GHz): 50-100 km (higher atmospheric attenuation limits interference range). Any terrestrial station within the coordination contour that operates co-frequency must be evaluated for potential interference before the earth station is licensed. The coordination contour is included in the coordination report filed with the FCC application.

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