This simulator alters audio signals as if they had reached a radio receiver at specific times of day/year via multiple propagation paths over long or medium wave according to ITU-R P.1407, ITU-R F.1487 and ITU-R P.368 (ground wave, sky wave).
Various ITU test profiles are taken into account, as well as ground conductivity (ITU-R P.527), radiation angle, and transmitter power.
ITU-R F.1487 profile lib
ITU_PROFILES = [
# --- MID LATITUDES ---
{"name": "Mid Lat Quiet", "delays": [0.0, 0.5, 1.0], "spread": 0.1},
{"name": "Mid Lat Moderate", "delays": [0.0, 1.0, 2.0], "spread": 0.5},
{"name": "Mid Lat Disturbed", "delays": [0.0, 2.0, 4.0], "spread": 1.0},
# --- LOW LATITUDES ---
{"name": "Low Lat Quiet", "delays": [0.0, 0.5, 1.2], "spread": 0.5},
{"name": "Low Lat Moderate", "delays": [0.0, 2.0, 4.5], "spread": 1.5},
{"name": "Low Lat Disturbed", "delays": [0.0, 6.0, 9.0], "spread": 10.0},
# --- HIGH LATITUDES ---
{"name": "High Lat Quiet", "delays": [0.0, 1.0, 2.5], "spread": 0.5},
{"name": "High Lat Moderate", "delays": [0.0, 3.0, 5.5], "spread": 10.0},
{"name": "High Lat Disturbed", "delays": [0.0, 7.0, 10.5], "spread": 30.0},
# --- (NVIS paths) ---
{"name": "NVIS Quiet", "delays": [0.0, 0.5, 0.8], "spread": 0.1},
{"name": "NVIS Disturbed", "delays": [0.0, 1.0, 1.5], "spread": 1.0},
{"name": "Equatorial Flutter", "delays": [0.0, 0.8, 1.6], "spread": 20.0}
]
# Ground Conductivity (sigma) in S/m according to ITU-R P.527
SIGMA_TYPES = [
("Sea Water", 5.0), # High Conductivity (Best for Groundwave)
("Wet Ground", 1e-2), # Good Propagation
("Dry/Rocky", 1e-3), # High Attenuation
("Urban/City", 1e-4) # Maximum Ground Loss
]There is a selection of different predefined transmitter locations relative to the receiver location.
RECV_LOC = {"name": "Frankfurt/Main", "lat": "50.1109", "lon": "8.6821"}
SENDER_PRESETS = [
# --- NORTH PATH ---
{"name": "Bieblach (N-Nah)", "lat": 50.91, "lon": 12.09, "sig_pref": 1, "desc": "Hessisch/Thüringisches Bergland (Feucht)"},
{"name": "Kopenhagen (N-Mid)", "lat": 55.67, "lon": 12.56, "sig_pref": 1, "desc": "Norddeutsche Tiefebene (Feucht)"},
{"name": "Stockholm (N-Far)", "lat": 59.32, "lon": 18.06, "sig_pref": 2, "desc": "Skandinavischer Schild (Trocken/Fels)"},
# --- SOUTH PATH ---
{"name": "Mühlacker (S-Nah)", "lat": 48.94, "lon": 8.85, "sig_pref": 1, "desc": "Südwestdeutsches Schichtstufenland (Feucht)"},
{"name": "Mailand (S-Mid)", "lat": 45.46, "lon": 9.18, "sig_pref": 2, "desc": "Alpen-Massiv (Trocken/Fels)"},
{"name": "Neapel (S-Far)", "lat": 40.85, "lon": 14.26, "sig_pref": 1, "desc": "Apennin/Küstenebene (Feucht)"},
# --- WEST/EAST-PATH ---
{"name": "Luxemburg (W-Nah)", "lat": 49.61, "lon": 6.13, "sig_pref": 3, "desc": "Urbanes Gebiet / Minette (Stadt)"},
{"name": "Prag (O-Mid)", "lat": 50.07, "lon": 14.43, "sig_pref": 2, "desc": "Böhmische Masse (Trocken/Fels)"},
{"name": "Bordeaux (W-Far)", "lat": 44.83, "lon": -0.57, "sig_pref": 1, "desc": "Französisches Sedimentbecken (Feucht)"}
]In addition to the inputs of the sound card installed in the system, WAV files or internet radio stations (stations.db, for example from the AMWaveSynth project https://github.com/radiolab81/AMWaveSynth) can also be used as source signals.
The audio signal, modified by the ground and sky wave paths, can be output in various ways: soundout, WAV file
Simple AM modulators for old historical radios, such as GFGF Konzertsender (https://www.radiomuseum.org/r/gfgf_konzertsender.html) or Le ModulAM (https://modulam.retrotechnique.org/); DDS-Heimsenderlein (https://www.radiomuseum.org/forum/gemeinschaftsprojekt_dds_heimsenderlein.html) and many others, enable an even more realistic simulation purely at the audio level.
Installation is as easy as 1-2-3 on Debian 12/13-Linux systems. Simply use the Python package manager uv or the command sequence from install_ionos_env.sh to create a virtual Python environment. From this environment, simply start "IONOS_SIM" with:
uv run ionos_sim.py