Telecom & Transport Tools
Microwave, fibre and transport engineering, worked out in your browser. Every formula is visible, every constant is derived rather than typed, and nothing you enter — coordinates, frequencies, equipment figures — leaves your device.
What these do and do not claim
No vendor figures are supplied. Receiver thresholds, radio capacities and antenna patterns come from you or from a datasheet. Inventing them produces a link budget that looks authoritative and is fiction, which is worse than no answer.
Models are named and bounded. A free-space budget is a free-space budget: rain, multipath and terrain diffraction are separate effects and are not in it. Where a figure is a planning convention rather than physics — 60% of the first Fresnel zone, K = 4/3 — it says so.
Nothing here certifies anything. Not structural loading, not electrical code, not frequency coordination, not regulatory compliance. Those need a qualified engineer and a signature, and a web page is not one.
Where the care went
Constants are derived, not remembered. The 32.44 in the free-space expression is 20·log10(4π/c) adjusted for kilometres and megahertz; the 17.32 in the Fresnel radius is the same idea for kilometres and gigahertz. Both are computed from the speed of light when the page loads, so changing the units cannot leave a stale number behind.
Distances are geodesic. Vincenty's method on the WGS-84 ellipsoid, not a spherical approximation — on a 50 km hop those differ by a couple of hundred metres, which is enough to move a path profile when the clearance question is marginal. Checked against Vincenty's own published test pair, where it agrees to a tenth of a millimetre.
Both antenna bearings are given. The back-azimuth is not the forward bearing plus 180 — the meridians converge, and on a long path the two differ by a fraction of a degree. With a narrow beam that is a real pointing error, so both are shown.
- Fibre loss budget, splice and connector chains, and the fibre colour conventions — next, on a shared optical engine.
- Optical transport: wavelength and frequency conversion, CWDM and DWDM channel plans, dispersion, PMD and a documented OSNR model.
- Availability and downtime, series and redundant path modelling, and shared-risk analysis — because two logical paths down the same duct are not diverse.
- Site infrastructure: −48 V loads, battery autonomy, rectifier sizing and heat.
- Terrain-driven path profiles. The geometry works today from elevations you supply; the question of where elevation data comes from, and what it costs in privacy, is a separate decision worth making deliberately.