1. 02 Apr, 2016 1 commit
  2. 01 Apr, 2016 1 commit
  3. 31 Mar, 2016 1 commit
    • Manolis Surligas's avatar
      Fix the doppler correction mechanism · 82c9ff28
      Manolis Surligas authored
      The doppler correction mechanism has successfully passed the first tests
      using the GPredict software for the radio control. The corrections seems
      to be quite smooth. The next step is to apply it at an audible signal.
      82c9ff28
  4. 28 Mar, 2016 2 commits
  5. 21 Mar, 2016 1 commit
  6. 08 Mar, 2016 1 commit
    • Manolis Surligas's avatar
      Finish the AX.25 decoder and add a UDP message source block · 0e0a3e0c
      Manolis Surligas authored
      The AX.25 decoder is now decoding the received frames.
      Also, the module now provides a UDP message source block. This block
      will be responsible to receive UDP packets and transform them into PMT
      messages for further processing in the GNU Radio flowgraph. As the
      communication with the satnogs-client will be done in the same host, we
      do not have to care about packet loss.
      
      Furthermore, the module now provides and a debug message  source block
      for easy debugging.
      0e0a3e0c
  7. 02 Mar, 2016 1 commit
  8. 27 Feb, 2016 1 commit
    • Manolis Surligas's avatar
      Improve the Morse decoder block · e9c6f36f
      Manolis Surligas authored
      The Morse decoding block has now the configuration parameter that
      enables an automatic estimation of the dot duration. Based on this
      estimation all other symbol durations are computed.
      e9c6f36f
  9. 19 Feb, 2016 1 commit
    • Manolis Surligas's avatar
      Matched filter for the FSK/AFSK demodulation · 07ff0054
      Manolis Surligas authored
      FSK demodulation can be implemented pretty well either using envelopes
      or matched filters. For now the matched filters seems to be a better
      candidate. However, some normalization issues should be solved.
      07ff0054
  10. 17 Feb, 2016 1 commit
  11. 09 Feb, 2016 1 commit
    • Manolis Surligas's avatar
      Started the AFSK decoder. · 27c597a8
      Manolis Surligas authored
      The clock recovery mechanism of GNU Radio is considered
      an overkill for the needs of AFSK. So the afsk_decoder
      will focus on a frequency domain approach.
      27c597a8
  12. 01 Feb, 2016 1 commit
    • Manolis Surligas's avatar
      Fix CW decoder issue · d07fd192
      Manolis Surligas authored
      The CW decoder was wrongly producing a Short Pause symbol instead of a
      dot symbol. With this fix the decoder can now reconstruct the initial
      text sequence sent.
      
      Also the CW matched filter now can directly produce the power of the
      filtered samples. This is very handy in order to get rid off an
      additional multiply block, saving vital resources especially for
      embedded platforms.
      
      For testing and demonstration purposes the morse_decoding_flowgraph can
      be used. The word sequence is the `HELLO WORLD`.
      d07fd192
  13. 30 Jan, 2016 1 commit
    • Manolis Surligas's avatar
      Improved Morse decoding · 1e210087
      Manolis Surligas authored
      The AGC block in the Morse decoding flowgraph is placed now at the
      proper position. The output of the matched filter produces now a clear
      and distinguishable signal during the presence of a pulse. This makes
      the work for the signal to symbol decoder more easy.
      1e210087
  14. 27 Jan, 2016 1 commit
    • Manolis Surligas's avatar
      CW signal to Morse Symbol decoding block · f8b84707
      Manolis Surligas authored
      The CW symbol decoder block takes as input the power of the processed
      signal and tries to identify the dot and dash symbols. It produces
      asynchronous messages containing the decoded symbols. The output
      messages can be directly used by the Morse code decoder block, in order
      to retrieve the clear text message.
      
      There are some few thing that need to be done for the block to be fully
      operational.
      f8b84707
  15. 24 Jan, 2016 1 commit
    • Manolis Surligas's avatar
      Add a generic clear text message sink. · 5d4884cf
      Manolis Surligas authored
      For now the generic clear text message sink just prints the decoded
      clear text messages in the stdout. In the future and depending the needs
      of the project, the clear text messages can be forwarded at other
      services on the same host or via the network.
      
      Also the debug message source block now supports injection of artificial
      errors, for more robust decoding of the Morse decoder block.
      5d4884cf
  16. 22 Jan, 2016 1 commit
    • Manolis Surligas's avatar
      Add Morse code debug source block · ebd07215
      Manolis Surligas authored
      Now, with the Morse code debug source block the testing of the decoder
      can begin.
      
      Add at the examples directory a small flowgraph that connects the debug
      source block with the decoder.
      
      ebd07215
  17. 21 Jan, 2016 1 commit
    • Manolis Surligas's avatar
      Morse tree traversal is working · d307d6ac
      Manolis Surligas authored
      Depending the received symbol the tree is traversed towards the leafs.
      At each step the corresponding decode-able character is appended at a
      string buffer. 
      
      TODOs: 
      * Add logic in the decoder to retrieve the decoded words from the tree
      * Create a debug source block  
      d307d6ac
  18. 19 Jan, 2016 1 commit
    • Manolis Surligas's avatar
      Add morse decoder block. · ca49f817
      Manolis Surligas authored
      The morse decoder is not yet functional. The decoding is performed
      using a binary tree. Left child, corresponds to a received dot whereas
      right to a received dash.
      ca49f817
  19. 17 Jan, 2016 1 commit
  20. 07 Jan, 2016 1 commit