Written by Lucas Teske
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Long-form field guide · GOES-13 · Published 2017

GOES Satellite Hunt

Build an L-band ground station and follow every transformation from radio-frequency samples to complete LRIT weather products. The guide connects practical RF hardware, GNU Radio, channel coding, CCSDS frames, packet transport, and image files as one system.

Start with the motivation Open Satellite Project
GOES-13 full-disk infrared image of Earth recovered from the LRIT broadcast
  1. Receive the L-band signal
  2. Recover BPSK symbols
  3. Decode CCSDS frames
  4. Extract virtual channels
  5. Assemble LRIT products

From a signal to an image

A practical record of the investigation, organized as a reusable technical guide.

This work began as a five-part blog series written while I was reverse engineering the GOES-13 downlink at the end of 2016. I reorganized it here to explain the complete receive chain coherently and to keep the material useful alongside the GOES-16 research that followed.

The investigation led directly to Open Satellite Project. Many of the same ideas also apply to weather satellites with related downlink protocols, including the Meteosat family.

Chapters

Read in order for the complete pipeline, or jump directly to the layer you are implementing.

01 Context

Motivation

Why receive GOES directly, what the project set out to prove, and how the complete system fits together.

Begin the guide
02 RF hardware

The hardware setup

Assemble the dish, build a cylindrical waveguide feed, add filtering and amplification, and point the antenna.

Build the receiver
03 Signal processing

The demodulator

Move the recorded spectrum to baseband, filter and resample it, recover carrier and clock, and output BPSK symbols.

Recover the symbols
04 Channel coding

Frame decoder

Find the attached sync marker, resolve phase ambiguity, apply Viterbi decoding, and recover fixed-size CCSDS frames.

Decode the frames
05 Transport

Packet demultiplexer

De-randomize the stream, correct Reed–Solomon errors, separate virtual channels, and reconstruct space packets.

Extract the packets
06 Products

Files and LRIT formats

Process LRIT headers, decompress Rice-coded imagery, name the products, and interpret the complete file catalogue.

Assemble the files
Browse the LRIT file reference Read the conclusion
Cite this work Plain text · BibTeX

Suggested citation

Lucas Teske. “GOES Satellite Hunt.” Lets Hack It, 2017. https://lucasteske.dev/goes-satellite-hunt/.

BibTeX

@misc{teske2017goessatellitehunt,
  author = {Teske, Lucas},
  title = {GOES Satellite Hunt},
  year = {2017},
  publisher = {Lets Hack It},
  url = {https://lucasteske.dev/goes-satellite-hunt/}
}