step-by-step guide to get started with scanning satellite communications.
📡 1. Hardware Requirements
RTL-SDR (budget option, limited frequency range)
HackRF One (full-duplex SDR with a wider frequency range)
NooElec SAWbird LNA (for boosting weak signals)
Wideband Antenna (e.g., helical, yagi, or dish antennas)
Low-Noise Amplifier (LNA) (to enhance weak signals)
Band-Pass Filter (to remove unwanted noise)
⚙️ 2. Software Setup You’ll need SDR software to process and analyze signals. Here are common tools:
SDR# (SDRSharp) – Best for RTL-SDR, beginner-friendly
GQRX – Cross-platform alternative
GNURadio – Advanced signal processing
SatDump – Satellite image decoding
WXtoImg – NOAA weather satellite image decoding
Orbitron – Real-time satellite tracking
🚀 3. Track Satellite Frequencies You need satellite frequency data to know what signals to scan. Use:
SatNOGS DB (https://db.satnogs.org/)
Gunter’s Space Page (https://space.skyrocket.de/)
N2YO (https://www.n2yo.com/) for live tracking
🔹 Common Satellite Frequencies:
| Satellite Type | Frequency Range
| NOAA Weather | 137–138 MHz
| GOES Weather | 1.69 GHz
| Inmarsat L-Band | 1.54 GHz
| Iridium | 1.616 GHz
| GPS | 1.575 GHz
| Amateur Radio Sats | 145-146 MHz & 435-438 MHz
| ISS SSTV | 145.800 MHz
📻 4. Receiving Signals
Using RTL-SDR:
Connect your RTL-SDR and antenna.
Open SDR# or GQRX.
Set Frequency (e.g., 137 MHz for NOAA).
Choose NFM (Narrowband FM) mode for voice/data or USB/LSB for weak signals.
Adjust gain and filter settings to improve reception.
Using HackRF:
Open GNURadio or SDR#.
Tune to higher frequency satellites (L-band, S-band).
Use external LNA and filters for weak signals.
Record and demodulate signals with GNURadio.
🌍 5. Decoding Satellite Signals
Some satellites transmit raw telemetry, APRS, SSTV, or weather images.
Weather Sats (NOAA/GOES): Use WXtoImg to decode images.
APRS (Amateur Packet Reporting System): Use Direwolf or Multimon-NG.
SSTV (Slow Scan TV from ISS): Use RX-SSTV to decode images.
Inmarsat L-band (Marine, Aviation Data): Use JAERO.
🛰️ 6. Real-Time Satellite Tracking
Use Orbitron or Gpredict to predict satellite passes over your location.
Enter your GPS coordinates.
Select target satellite.
Note the Doppler shift and adjust frequency accordingly.
DO NOT TRANSMIT on satellite bands (FCC/ITU regulations).
DO NOT DECRYPT encrypted military or commercial signals.
DO NOT INTERFERE with licensed satellite operations.
🛠️ Step 1: Choosing a Target Satellite
First, decide what type of satellite signals you want to receive:
Weather Satellites (NOAA, GOES) → Receives weather images
Amateur Radio Sats (ISS, SO-50, AO-91) → APRS, SSTV, Voice
Navigation Satellites (GPS, Galileo, GLONASS) → Positioning signals
Communications Satellites (Inmarsat, Iridium) → L-band data, voice
Use N2YO or Gpredict to track satellites and find their frequencies.
📌 Recommended Tracking Tools:
🔗 SatNOGS Database → Find active satellite frequencies
🔗 N2YO → Live satellite tracking
🔗 Gpredict → Predict satellite passes
📡 Step 2: Setting Up Your Hardware
For RTL-SDR (Beginner)
✅ Works well for 137-138 MHz (NOAA Weather, Amateur Radio)
✅ Affordable but limited to ~1.7 GHz max
Required Equipment:
RTL-SDR v3
V-Dipole or Helical Antenna (for NOAA weather sats)
Low-Noise Amplifier (LNA) (to boost weak signals)
Band-Pass Filter (to remove interference)
For HackRF (Advanced)
✅ Covers a wider 1 MHz – 6 GHz range (L-band, S-band)
✅ Can capture higher frequency signals (Inmarsat, Iridium, GPS)
Required Equipment:
HackRF One
Helical, Yagi, or Parabolic Dish Antenna (depends on frequency)
Bias-T LNA (e.g., NooElec SAWbird) for weak signals
TCXO Module (reduces frequency drift)
⚙️ Step 3: Installing SDR Software
Choose software depending on your SDR and OS:
📌 Windows:
SDR# (SDRSharp) → Best for RTL-SDR
WXtoImg → NOAA Weather decoding
Orbitron → Real-time satellite tracking
📌 Linux (ParrotOS, BlackArch):
sudo apt install gqrx-sdr gnuradio gr-satellites sox
SatDump → Powerful satellite signal decoder
sudo apt install rtl-sdr hackrf (for SDR drivers)
🛰️ Step 4: Receiving Satellite Signals
🔹 NOAA Weather Satellites (137 MHz)
1️⃣ Open GQRX or SDR#
2️⃣ Set frequency to 137.1 - 137.9 MHz
3️⃣ Choose Narrowband FM (NFM) mode
4️⃣ Adjust gain & filter to reduce noise
5️⃣ Save the audio file & decode with WXtoImg
🎯 Example Frequencies:
NOAA-18: 137.9125 MHz
NOAA-19: 137.1000 MHz
Meteor-M2 (Digital): 137.900 MHz
🔹 ISS (International Space Station) SSTV & APRS
SSTV Images: 145.800 MHz (Slow-Scan TV)
APRS Packets: 145.825 MHz (Automatic Packet Reporting System)
Use RX-SSTV to decode ISS images.
🔹 L-Band Communications (1.5 – 1.7 GHz)
Requires HackRF + LNA + SAW filter.
📡 Common Signals:
Inmarsat (1.54 GHz) → Maritime, aviation text messages
Iridium (1.61 GHz) → Satellite phones
GOES Weather (1.69 GHz) → High-resolution weather data
📌 Software for Decoding:
JAERO (Inmarsat ACARS decoding)
SatDump (GOES satellite image decoding)
✅ Legal: Passive signal reception & analysis
🚫 Illegal: Transmitting, decrypting private/military signals