init

srctmp/main.rs

@@ -0,0 +1,60 @@
+use ldpc::{
+    channel::{AwgnChannel, Channel},
+    code::{CodeTopology, GenerationMethod, LdpcCode, LdpcParams},
+    decoder::{build_decoder, DecoderConfig, DecoderMethod},
+    encoder::{build_encoder, EncodingMethod},
+};
+use rand::{Rng, SeedableRng};
+
+fn main() -> ldpc::Result<()> {
+    // ── 1. Générer le code ────────────────────────────────────────────────────
+    let params = LdpcParams {
+        n: 100,
+        k: 50,
+        topology: CodeTopology::Regular { wc: 3, wr: 6 },
+        generation: GenerationMethod::MacKayNeal { max_attempts: 500 },
+        seed: Some(42),
+    };
+    let mut code = LdpcCode::new(params)?;
+    println!(
+        "Code LDPC : n={}, k={}, taux={:.2}, girth={}",
+        code.n(),
+        code.k(),
+        code.rate(),
+        code.girth()
+    );
+
+    // ── 2. Encodeur ───────────────────────────────────────────────────────────
+    let encoder = build_encoder(&mut code, EncodingMethod::Systematic)?;
+
+    // ── 3. Canal ──────────────────────────────────────────────────────────────
+    let channel = AwgnChannel::new(2.0, code.rate())?; // 2 dB Eb/N0
+    println!("Capacité AWGN ≈ {:.4} bits/utilisation", channel.capacity());
+
+    // ── 4. Décodeur ───────────────────────────────────────────────────────────
+    let decoder = build_decoder(&code, DecoderMethod::SumProduct, DecoderConfig::default());
+
+    // ── 5. Simulation ─────────────────────────────────────────────────────────
+    let mut rng = rand::rngs::StdRng::seed_from_u64(123);
+    let n_trials = 100;
+    let mut errors = 0usize;
+
+    for _ in 0..n_trials {
+        // Message aléatoire
+        let message: Vec<u8> = (0..code.k()).map(|_| rng.gen::<u8>() & 1).collect();
+        // Encodage
+        let codeword = encoder.encode(&message)?;
+        // Transmission AWGN
+        let received_llr = channel.transmit(&codeword, &mut rng);
+        // Décodage
+        let result = decoder.decode(&received_llr);
+        // Vérification
+        if !result.is_success() {
+            errors += 1;
+        }
+    }
+
+    let ber = errors as f64 / n_trials as f64;
+    println!("FER sur {} essais à 2dB : {:.2}%", n_trials, ber * 100.0);
+    Ok(())
+}