GHCT — Ground-to-HAPS Communication Simulator
The Ground‑HAPS Communication Tool (GHCT) is a specialized Monte‑Carlo simulator for analyzing communication links between a ground station and a High‑Altitude Platform Station (HA
Overview
The Ground‑HAPS Communication Tool (GHCT) is a specialized Monte‑Carlo simulator for analyzing communication links between a ground station and a High‑Altitude Platform Station (HAPS) operating in the stratosphere (typically 15–30 km). It is delivered as a self‑contained Windows application — a single executable (.exe) with no MATLAB, MATLAB Runtime, or Python installation required. Within one unified environment, GHCT models both Free‑Space Optical (FSO) and Radio‑Frequency (RF) ground‑to‑HAPS links (uplink or downlink), capturing the dominant impairments of the stratospheric channel — atmospheric turbulence, multi‑layer attenuation, pointing/misalignment error, and angle‑of‑arrival fluctuation for the optical link; multipath fading and ITU‑R propagation losses for the radio link — to produce statistically rigorous estimates of link performance. Its channel and propagation models are externally validated against ITU‑R reference datasets and peer‑reviewed literature. GHCT is built for researchers, system designers, and network planners working on next‑generation non‑terrestrial networks (NTN), 6G backhaul, stratospheric relay, remote sensing, and disaster‑recovery connectivity.
Key features
- Dual link‑type analysis — model an FSO or an RF ground‑to‑HAPS link from a single interface; the workspace adapts its inputs and physics to the selected channel.
- FSO turbulence models — Lognormal, Gamma‑Gamma, F (Fisher–Snedecor), M laga (ℳ), Weibull, and Exponentiated‑Weibull, driven by a Hufnagel–Valley (HV 5/7) Cₙ profile and Rytov‑variance scintillation.
- Layered atmospheric attenuation (FSO) — a Beer–Lambert slant‑path model partitioned into clear‑air (Kim/Kruse visibility), cloud, fog, and stratospheric volcanic‑aerosol layers, with wavelength‑dependent extinction.
- Pointing error & misalignment — Rayleigh, Hoyt, and Beckmann jitter statistics with Gaussian‑beam geometry (boresight + jitter).
- Angle‑of‑Arrival (AoA) fluctuation — turbulence‑induced wavefront tilt with receiver field‑of‑view masking.
- Reference‑grade RF propagation (ITU‑R) — rain (P.838‑3 / P.618‑14 slant‑path with P.839‑4 rain height), gaseous absorption (P.676), cloud (P.840‑8 double‑Debye), tropospheric scintillation (P.618), and free‑space path loss.
- RF multipath fading — Nakagami‑m, Rician, and Shadowed‑Rician models with elevation‑dependent K‑factor and land‑mobile‑satellite shadowing presets.
- Performance metrics — Average Bit Error Rate (BER), Outage Probability, Ergodic Channel Capacity, and a full Link Budget (FSO received SNR from a shot+thermal‑noise receiver model; RF carrier‑to‑noise ratio with sky‑noise coupling).
- Modulation support — OOK (IM/DD), BPSK, M‑PSK, and M‑QAM (coherent/heterodyne).
- Monte‑Carlo engine — large‑sample statistical averaging with parameter sweeps over SNR, visibility, altitude, elevation angle, wavelength, aperture, carrier frequency, rain rate, link distance, and transmit power.
Use cases
- Telecom / NTN operators — dimensioning HAPS‑based backhaul, feeder, and coverage links for 5G/6G non‑terrestrial networks.
- Aerospace & platform developers — link‑budget and availability analysis for stratospheric platforms used in relay, surveillance, and Earth observation.
- Academia & research — study of optical and RF channel impairments, turbulence/fading statistics, and ITU‑R propagation for ground‑to‑stratosphere links.
- Defense & government — planning of resilient high‑altitude optical and RF communication links.
- Disaster‑response organizations — rapid modeling of temporary HAPS‑based connectivity for post‑disaster or hard‑to‑reach areas.
System requirements
- Operating system: Windows 10 / 11 (64‑bit).
- Dependencies: None — ships as a self‑contained executable. No MATLAB, MATLAB Runtime, or Python required.
- Memory: 4 GB RAM minimum (8 GB recommended for large Monte‑Carlo runs).
- Internet: Not required for operation (fully offline); a one‑time online activation is used for licensing (hardware‑locked, RSA‑2048).