Communication System README

This repository contains a Python-based transmitter/receiver system for sending 40-character text messages over a simulated noisy channel (local or remote server).

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Prerequisites

• Python 3.7+
• NumPy

Install dependencies:

pip install numpy

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Files

• encoder.py — builds codebook and encodes messages.
• decoder.py — decodes received samples back into text.
• channel.py — local channel simulator.
• client.py — client stub to send samples to the remote server.
• main.py — main driver: wraps encode → channel → decode, plus performance testing.

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Usage

All commands assume you are in the project root directory.

1. Test locally for 1 trial

python3 main_backup.py \
  --message "Lorem ipsum dolor sit amet. consectetuer" \
  --trials 1 \
  --mode local

2. Test locally for 500 trials

python3 main_backup.py \
  --message "Lorem ipsum dolor sit amet. consectetuer" \
  --trials 500 \
  --mode local

3. Test on the remote server (1 trial)

This will write input.txt and output.txt in your working directory.

python3 main_backup.py \
  --message "Lorem ipsum dolor sit amet. consectetuer" \
  --trials 1 \
  --mode server \
  --input_file input.txt \
  --output_file output.txt \
  --hostname iscsrv72.epfl.ch \
  --port 80

After running, input.txt contains your transmitted samples, and output.txt contains the noisy output from the server.

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Manual decoding of server output

If you want to decode output.txt yourself:

python3 - << 'EOF'
import numpy as np
import encoder, decoder

# Load noisy samples
Y = np.loadtxt("output.txt")

# Rebuild codebook
C = encoder.make_codebook(r=5, num_blocks=40)

# Decode
msg = decoder.decode_blocks(Y, C)
print("Decoded message:", msg)
EOF

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Feel free to adjust --trials or swap between local and server modes as needed.