Code for ground segment signal processing, error correction and cryptography

MSK Encoder

Reads in .txt file and outputs .wav file with MSK encoded message

carrier_A - use 1

carrier_f - use anything between 6000 and 14000. Expected carrier frequency will be 10000

bit_rate - will be 6000

sample_rate - needs to be 48000

message - .txt file name with message to encode: must be in the directory

output_file_name - .wav file name for output MSK signal

To run:

1. Make sure there is a message file in the same directory or specify the path in the script when you call the function.
2. Run the function, it will generate a .wav file.

MSK Demodulator

Reads in the .wav file and outputs demodulated bits

input_file - this is the output from msk_encode_v2_1_2

bit_rate - default set to 6000 as this is what the bit rate should be

It will generate a .BIN file with the demodulated message.

Notes: needs to operate at 48000 Hz sample rate, 6000 bps and the start of the message must be the sync key '00101010'

To run:

1. Make sure the .wav file is in the same directory or specify the path in the script when you call the function
2. Run the function, it will generate a .BIN file

bcjr Decoder

Performs Turbo decoding on raw input

TODO

• Port MSK code to gui-app and telecommand-server
• Port bcjr decoder to gui-app and make encoder for telecommand-server
• Write SHAKE128 hashing function