Description
You need to send a message in Morse code with a two-state frequency modulation.
The chosen encoding is as follows: the . and - are represented by a pure carrier at a frequency of 5kHz, and the gaps are represented by a pure carrier at a frequency of 1kHz.
You must send CAN I GET THE FLAG.
You have the server code and a sample message available.
The transmission parameters are as follows:
- sampling rate: 24kHz,
- sending of a
.: pure carrier of frequency 5kHz during 1 millisecond, - duration of a
-: pure carrier of 5kHz frequency for 5 milliseconds, - spacing between two letters: pure carrier of frequency 1kHz during 5 milliseconds,
- spacing between two words: pure carrier of frequency 1kHz during 20 milliseconds.
This challenge has been split into three parts:
Files
- docker-compose.yml
-
mommy-morse.py
3.83 KiB – 9e372d5244e6a1eab67cafeae3abb53daadeb4e61c154ce18f222f73e574f3e5 -
client.py
312 B – e23fa175a943fb6943918e9a2ba3cef3d37678a151047aae962fd23ada3f17d5 -
signal.iq
11.53 KiB – abaf0cabdda55a40f9707ea12813ab701b3b052142af9838a282199835416695
Author
ElyKar
Challenge Instructions
- First, download docker-compose.yml:
curl https://hackropole.fr/challenges/fcsc2022-hardware-mommy-morse/docker-compose.public.yml -o docker-compose.yml - Launch the challenge by executing in the same folder:
docker compose up - Then, in another console, access the challenge with Netcat:
nc localhost 4000
In case you encounter problems, please consult the FAQ.
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