Satellite coverage tools compared:
NetSim Astra, Ansys STK, MATLAB
RF planning · Coverage maps · Link budgets · Access reports
Three tools can produce a satellite RF coverage study, and they get there very differently. This page compares them for one workflow, producing and validating an RF coverage map over a region, and states plainly where each tool wins.
Three tools, three workflows
Each tool approaches a coverage study from its own home ground.
Ansys STK
Orbit mechanics is the reference frame, and a communications study is assembled around it: Transmitter and Receiver objects per asset, a CoverageDefinition, grid constraints, and figures of merit, exported report by report.
Home ground: orbit design, manoeuvre planning, attitude and sensors, conjunction assessment, multi-domain scenarios.
MATLAB + Satellite Communications Toolbox
Each step of the coverage workflow is code the analyst writes: the scenario, the grid, the link loop, the plots. There is no GUI path to a coverage map in the current release; the helper functions live in the team's codebase.
Home ground: 5G NTN and DVB-S2X waveform chains, GNSS signal generation, channel modelling, algorithm development.
NetSim Astra
A web-based tool built for exactly this workflow. Select the constellation, set the RF parameters and region, and run: one pass produces the coverage heatmap, the access and gap report, and per-sample CSVs with C/N0, C/N, G/T, BER and PFD at every grid point.
Home ground: coverage studies, link budgets, PFD screening, access reports, by any RF or systems engineer, with no programming.
The coverage-mapping workflow, side by side
A condensed view. The detailed Q&A carries the full table with sources.
| Capability | Ansys STK | MATLAB with toolboxes | NetSim Astra |
|---|---|---|---|
| Setting up a coverage study | ● Tx/Rx objects per asset, a CoverageDefinition, and a hand-wired Grid Constraint and Figure of Merit | ✗ No GUI path; scenario, grid, link loop and plots are user code | ✓ Three tabs in a browser and a Run button |
| Who can run it | ● An STK user trained on the object model | ● A user who writes .m code |
✓ Any RF or systems engineer, with no programming |
| Comm metrics across the grid | ● Via an Access Constraint FOM referencing a Receiver constraint | ● sigstrength in a user-written
loop |
✓ C/N0, C/N, G/T, BER and PFD at every grid point, by default |
| Land-use clutter loss | ✗ No land-cover clutter classes documented | ✗ No ITU-R P.2108 clutter-loss model in the toolbox | ✓ ESA WorldCover class per grid point, 11 editable clutter classes |
| Regulatory PFD screening | ● PFD as receiver constraints; no Article 21 limit mask documented | ✗ No PFD function or limit mask in the toolbox | ✓ ITU RR Article 21 style limit mask, margin per sample |
| Deployment | ● Windows and Linux desktop | ● Desktop per analyst | ✓ Browser-based, multi-user; deploys on your server |
✓ included and integrated ● possible, with additional configuration or scripting ✗ not available in this workflow, per the vendor's public documentation. Assessed for the coverage-mapping workflow only, against vendor documentation retrieved July 2026. Astra entries reflect NetSim Astra v1.0.
Where STK and MATLAB win
Astra does not replace either tool. It covers the coverage-planning workflow; the tools are used alongside one another.
Stay in STK for
- Orbit design, manoeuvre planning, station-keeping, and lifetime analysis
- Attitude, pointing, sensor tasking, and multi-domain scenarios
- Conjunction assessment, launch windows, and mission timelines
- Terrain-driven propagation along the path
Astra's access report follows the Figure of Merit definitions Ansys publishes, so an Astra study and an existing STK study can be placed side by side.
Stay in MATLAB for
- 5G NR NTN waveform chains: PDSCH processing, Doppler pre-compensation, HARQ
- DVB-S2 and DVB-S2X waveform generation and RF impairment studies
- GNSS signal and code generation
- Algorithm development in code
Astra reads Ansys HFSS FFD antenna pattern files and CSV gain tables directly, so patterns simulated or measured elsewhere drop into a coverage run.
What none of the three does
Packet-level network simulation
A coverage map says where the link closes. It does not say what throughput a user gets when the scheduler, the protocol stack, and the traffic load enter the picture. That is the job of NetSim's NTN library: the same scenario simulated end to end, packet by packet, per 3GPP TR 38.821.
- Full 5G protocol stack over the satellite link
- Scheduling, beams, and interference under load
- Application throughput, latency, and availability
Go deeper
The product page, the detailed comparison, and an evaluation.
Ansys, STK and HFSS are trademarks of Ansys, Inc. MATLAB and Satellite Communications Toolbox are trademarks of The MathWorks, Inc. Tetcos is not affiliated with either vendor; the comparison reflects their public documentation as retrieved in July 2026.