Spectrum dial and calculators
Every band a US satellite system can use or is asking for, from 600 MHz to the D-band, on one dial, followed by calculators for spectrum and orbit. Move across the dial to see what is where; click a block or a band to load its details below the dial.
Built from the FCC Table of Frequency Allocations (47 CFR 2.106), 47 CFR 25.202, the SCS rules (FCC 24-28), the Spectrum Abundance proceeding (FCC 25-29 and the September 30, 2026 items), and the transactions below. A summary for orientation; verify against the current rule text before relying on it. Last checked September 13, 2026.
Calculators
Spectrum and orbit calculators using the same models Apogee uses in engagements. Open a calculator, change the inputs, and read the result; each states its method.
SpectrumInterference and GSO protection
What one NGSO satellite does to a GSO earth station: power flux density in the reference bandwidth, interference-to-noise ratio, and the equivalent temperature rise, against the coordination trigger and an EPFD limit you enter.
Earth station gain off axis from the ITU-R S.465 reference pattern (32 - 25 log theta between 1 and 48 degrees, -10 dBi beyond); on-axis gain from the diameter and frequency at 65 percent efficiency. The EPFD shown is the single-entry value from this one satellite; the Article 22 limits apply to the aggregate over the constellation and the percentage of time.
Interference to noise, I/N
0dB
The 6 percent delta T/T trigger (I/N of -12.2 dB) is the ITU-R coordination threshold for GSO networks. Domestically, FCC 26-26 replaced EPFD limits with throughput and availability criteria; internationally, Article 22 still applies.
SpectrumSpectrum and capacity planner
Licensed bandwidth, polarization, and frequency reuse turned into bandwidth per beam and capacity per beam, per satellite, and per megahertz of spectrum.
Each beam gets one color and one polarization: bandwidth per beam is licensed bandwidth divided by colors. Spectral efficiency is the Shannon limit at the design C/N, reduced by the implementation loss; 2 dB is typical of DVB-S2X or 5G NR at this C/N.
System capacity in the region
0Gbps
A planning number. Delivered capacity depends on beam hopping, traffic distribution, interference from neighboring systems, and the terminal population, and a coordination agreement can reduce it.
SpectrumLink budget and rain fade
A downlink or crosslink budget from EIRP to margin, with slant range derived from altitude and elevation. Rain fade comes from the tool below.
Link margin
0dB
Free-space path loss plus the losses you enter. Atmospheric absorption and pointing loss belong in the losses field; rain in its own.
Rain fade for this link
ITU-R P.838 specific attenuation with the P.618 path reduction. Apply the result to the link budget above.
42 mm/h is a temperate mid-latitude value; tropical sites run 90 to 150 mm/h. Rain height is roughly the 0°C isotherm plus 0.36 km.
Rain attenuation, 0.01% of the year
0dB
Coefficients interpolated from ITU-R P.838-3; path reduction from the P.618 method; 0.1% and 1% values from the P.618 percentage scaling. Good for sizing margin, not for a filing.
OrbitWalker constellation designer
Planes, satellites per plane, altitude, inclination, and elevation mask turned into coverage: footprint, satellites in view by latitude, the latitude limit, and the ground tracks of every plane over one orbit.
Satellites in view uses the latitude density of an inclined circular orbit against a uniform sphere; results are averages over time, not minimums. Operators use phasing and multiple shells to close the gaps an average does not show.
Satellites in view at 45 degrees latitude, average
0
OrbitDoppler and pass geometry
For one pass over a ground station or a handset: duration above the mask, slant range, Doppler shift and its rate of change at closest approach, and the Doppler curve the receiver has to track.
Circular orbit, ground station fixed in an inertial frame (Earth rotation neglected, which understates duration by a few percent for equatorial passes). Doppler rate is what a handset or modem must track; 3GPP Release 17 pre-compensates it from the satellite ephemeris.
Maximum Doppler shift in the pass
0kHz
OrbitDeorbit estimator
Natural decay lifetime from a circular orbit, checked against the FCC five-year disposal rule, plus the delta-v and propellant to shorten it.
Estimated natural lifetime
0years
Exponential atmosphere model, circular orbit, drag only. Solar activity scales density by 0.4, 1, or 4. Propellant from the rocket equation using spacecraft mass as initial mass. The lifetime from the disposal perigee is the circular-orbit equivalent; the elliptical orbit decays faster. For planning, not for propellant sizing or a filing.
Bands opening and bands leaving
The satellite allocations are moving up in frequency. Below about 4 GHz, spectrum is being reassigned from satellite to 5G; above 40 GHz, new satellite allocations are being added.
Opening now
1,050 MHz: the 12.7 GHz band (550 MHz, next to the Ku downlinks every NGSO system uses) and the 42 GHz band (500 MHz, never occupied). The Spectrum Abundance Report and Order is scheduled for the FCC's September 30, 2026 vote, for home broadband, aircraft and ship terminals, inter-satellite links, and gateway traffic. Not reserved for any one operator.
Proposed next
The same meeting carries a further notice on up to 1,459 MHz more in the Ku- and Ka-bands and 138.25 GHz in the D-band for satellite communications and spacecraft control. Still open from May 2025: 51.4-52.4 GHz as a V-band uplink and four W-band segments totaling about 17.9 GHz.
Reassigned to terrestrial
The lower C-band went to 5G in 2021 for about $81 billion; the upper C-band (160 MHz) follows by July 2027, leaving fixed-satellite service 60 MHz at 4.14-4.2 GHz in the contiguous US. Auctions planned for 2028 target 2.7 GHz and two unnamed bands. 12.2-12.7 GHz was the exception: it stayed with satellite in 2023.
Atmospheric attenuation by frequency
Clear-air absorption peaks at the water vapor line near 22 GHz and the oxygen lines at 60 and 119 GHz; the satellite bands sit in the windows between them, and rain adds to everything above 10 GHz. The W-band and D-band proposals are the next windows up.
Clear-air curve after ITU-R P.676 at sea level, 15 °C and 7.5 g/m³ water vapor, read from the standard figure; rain curve from ITU-R P.838 coefficients at 42 mm/h. Both approximate to about 20 percent; a filing uses the full recommendation with the site's climate data.
Direct to device: the bands below 2.5 GHz
Direct-to-device spectrum comes in two kinds: cellular bands leased from a partner carrier under the SCS rules, and mobile-satellite bands the operators buy outright.
Protection limits in a shared band
The NGSO downlink to its own terminal spills into the GSO earth station through the station's sidelobes. Two ways to bound it: a limit on the power flux density arriving at the GSO station from each direction (the EPFD masks of ITU Article 22), or a limit on what the GSO link loses (the throughput and availability criteria of FCC 26-26). Keeping the NGSO satellite outside an avoidance angle around the GSO arc is how systems have met the first; the second lets them shrink that angle.
The interference tool runs this geometry with numbers: PFD at the earth station, I/N, and delta T/T against the coordination trigger and an EPFD limit.
Spectrum holdings by operator
| Operator | Broadband bands | Direct to device and MSS | Where it is going |
|---|---|---|---|
| Starlink (SpaceX) | Ku user links (10.7-12.7, 14.0-14.5 GHz), Ka gateways (17.7-20.2, 27.5-30 GHz), V-band folded into Gen2, E-band gateway links | PCS G block by lease from T-Mobile; AWS-4, H block and unpaired AWS-3 from EchoStar pending transfer (about 65 MHz) | 12.7 GHz and 42 GHz once the September 30 order takes effect; 20.2-21.2 and 30-31 GHz requests pending at the FCC |
| Amazon Leo | Ka-band user and gateway links (17.7-20.2, 27.5-30 GHz); V-band filings | Globalstar's Band 53/n53 and MSS spectrum once the acquisition closes (2027) | EPFD waiver granted February 2026; same new bands as the other NGSO systems |
| OneWeb (Eutelsat) | Ku user links, Ka gateways | None announced | Second-generation system planning under the new sharing rules |
| AST SpaceMobile | Gateway links in Q/V and Ka | 700 and 800 MHz by coordination with AT&T, Verizon, and FirstNet; 45 MHz of L-band from Ligado; 248 satellites authorized April 2026 | Half the constellation by August 2030; country-by-country authorizations abroad |
| Globalstar | None | Big LEO 1.61-1.6265 and 2.4835-2.5 GHz, Band n53 terrestrial authority | Acquisition by Amazon expected to close in 2027 |
| Iridium | None | Upper Big LEO band near 1.62 GHz for voice, data, and messaging | Direct-to-device messaging services on existing spectrum |
| Viasat and Inmarsat | Ka-band GSO broadband | L-band MSS for aviation, maritime, and safety services | GSO protection criteria under FCC 26-26 shape coordination with the NGSO systems above |
| SES and Intelsat | C-band video and data in the remaining 4.14-4.2 GHz, Ku and Ka GSO, O3b MEO Ka | None | Compressed by the Upper C-band auction; compensated in the 2021 and 2026 clearings |
Operator holdings summarized from the authorizations and transactions on this page and the timeline; confirm current status in ICFS before relying on it for a filing. Bands still to be allocated, with their stage and expected bidders, are on the pipeline board.
Satellite bandwidth by band
In use today in blue; opening or proposed in green. Each step up in frequency roughly doubles the bandwidth on offer and raises the rain and gaseous losses the link has to carry; the rain fade and capacity tools show both.
Bandwidth totals are the satellite allocations summarized on the map above, downlink and uplink combined, for the contiguous US. The higher bands are wide because propagation limits them to short paths and large antennas; the rain fade tool shows a 20 GHz link losing 23 dB at 30° elevation in heavy rain, and losses grow with frequency.
Frequency allocation events on the timeline Spectrum pipeline Interference tool
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