.. titre : Perte de trajet dans l'espace libre RF
.. slug : rf-freespacepathloss
..date: 2025-12-26 15:00:00 UTC
.. tags : réseau, calculatrice, outil
.. catégorie : Calculatrices
.. lien :
.. description : Calculez la perte de trajet en espace libre (FSPL) en utilisant la fréquence et la distance. Utilisé pour la planification de liaisons micro-ondes point à point et l'analyse de la couverture WiFi extérieure.
.. tapez : texte
<style>
    .rf-calc-container {
        max-width: 1000px;
        margin: 20px auto;
        padding: 20px;
    }

    .calc-header {
        margin-bottom: 30px;
        padding: 25px;
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        border-radius: 12px;
        box-shadow: 0 4px 6px rgba(0,0,0,0.1);
        color: white;
    }

    .calc-header h2 {
        margin-top: 0;
        color: white;
        font-size: 28px;
        margin-bottom: 10px;
    }

    .calc-header p {
        margin: 10px 0;
        opacity: 0.95;
        font-size: 15px;
    }

    .input-grid {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 15px;
        margin-top: 20px;
    }

    .form-group {
        display: flex;
        flex-direction: column;
    }

    .form-group label {
        font-size: 14px;
        margin-bottom: 8px;
        color: white;
        font-weight: 500;
    }

    .form-group input {
        padding: 14px;
        font-size: 16px;
        border: 2px solid rgba(255,255,255,0.3);
        border-radius: 6px;
        font-family: 'Courier New', monospace;
        background: rgba(255,255,255,0.95);
        transition: all 0.3s ease;
    }

    .form-group input:focus {
        outline: none;
        border-color: #4CAF50;
        background: white;
        box-shadow: 0 0 0 3px rgba(76, 175, 80, 0.1);
    }

    .submit-button {
        margin-top: 20px;
        padding: 14px 35px;
        font-size: 16px;
        background: #4CAF50;
        color: white;
        border: none;
        border-radius: 6px;
        cursor: pointer;
        font-weight: bold;
        transition: all 0.3s ease;
        box-shadow: 0 2px 4px rgba(0,0,0,0.2);
    }

    .submit-button:hover {
        background: #45a049;
        transform: translateY(-1px);
        box-shadow: 0 4px 8px rgba(0,0,0,0.3);
    }

    .submit-button:active {
        background: #3d8b40;
        transform: translateY(0);
    }

    .result-section {
        background: white;
        border: 1px solid #e0e0e0;
        border-radius: 8px;
        margin-top: 30px;
        overflow: hidden;
        box-shadow: 0 2px 4px rgba(0,0,0,0.05);
        transition: all 0.3s ease;
    }

    .result-section:hover {
        box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    }

    .section-header {
        background: linear-gradient(135deg, #4CAF50 0%, #45a049 100%);
        color: white;
        padding: 15px 20px;
        font-size: 18px;
        font-weight: bold;
    }

    .section-content {
        padding: 20px;
        background: #fafafa;
    }

    .data-row {
        display: flex;
        margin: 12px 0;
        padding: 10px;
        background: white;
        border-radius: 4px;
        border-left: 3px solid #4CAF50;
    }

    .data-label {
        font-weight: bold;
        color: #555;
        min-width: 300px;
        flex-shrink: 0;
    }

    .data-value {
        color: #333;
        font-family: 'Courier New', monospace;
        word-break: break-word;
    }

    .data-value.highlight {
        color: #4CAF50;
        font-weight: bold;
        font-size: 18px;
    }

    .help-text {
        margin-top: 15px;
        font-size: 14px;
        color: rgba(255,255,255,0.9);
        background: rgba(0,0,0,0.1);
        padding: 10px 15px;
        border-radius: 4px;
    }

    .help-text strong {
        color: white;
    }

    /* Responsive design */
    @media (max-width: 768px) {
        .input-grid {
            grid-template-columns: 1fr;
        }

        .data-row {
            flex-direction: column;
        }

        .data-label {
            margin-bottom: 5px;
            min-width: auto;
        }

        .submit-button {
            width: 100%;
        }
    }
</style>
<div class="rf-calc-container">
<div class="calc-header">
<h2>Calculateur de perte de trajet en espace libre RF</h2>
<p>Calculez la perte sur le trajet en espace libre pour les transmissions radiofréquences en fonction des gains de distance, de fréquence et d'antenne.</p>
<div class="input-grid">
<div class="form-group">
<label for="distance">Distance (km) :</label>
<input id="distance" placeholder="e.g., 5" type="text" value="5"/>
</div>
<div class="form-group">
<label for="frequency">Fréquence (MHz) :</label>
<input id="frequency" placeholder="e.g., 2400" type="text" value="2400"/>
</div>
<div class="form-group">
<label for="txGain">Gain de l'antenne d'émission (dBi) :</label>
<input id="txGain" placeholder="e.g., 0" type="text" value="0"/>
</div>
<div class="form-group">
<label for="rxGain">Gain de l'antenne de réception (dBi) :</label>
<input id="rxGain" placeholder="e.g., 0" type="text" value="0"/>
</div>
</div>
<button class="submit-button" onclick="freeSpacePathLoss()" type="submit">Calculer</button>
<div class="help-text">
<strong>Note:</strong>La perte de trajet en espace libre représente l'atténuation du signal entre l'émetteur et le récepteur dans un environnement idéal sans obstacles. Les gains d'antenne sont ajoutés pour compenser la perte de trajet.</div>
</div>
<div class="result-section" id="results" style="display: none;">
<div class="section-header">Résultats</div>
<div class="section-content">
<div class="data-row">
<div class="data-label">Perte de trajet en espace libre (linéaire) :</div>
<div class="data-value highlight" id="fsplResult">-</div>
</div>
<div class="data-row">
<div class="data-label">Puissance reçue (dB) :</div>
<div class="data-value highlight" id="fsplResultindB">-</div>
</div>
</div>
</div>
</div>
<script>
function freeSpacePathLoss() {
    // Set variables from input
    var distance = Number(document.getElementById("distance").value);
    var frequency = Number(document.getElementById("frequency").value);
    var pi = Math.PI;

    var txGain = Number(document.getElementById("txGain").value);
    var rxGain = Number(document.getElementById("rxGain").value);

    // Free Space Path Loss
    var fspl = (Math.pow((4*pi*distance*frequency)/299792458,2))-txGain-rxGain;

    // Free Space Path Loss in dB
    var fsplResultindB = (20*Math.log10(distance)+20*Math.log10(frequency)+32.44)-txGain-rxGain;

    // Print results
    document.getElementById("fsplResult").innerHTML = fspl.toFixed(6);
    document.getElementById("fsplResultindB").innerHTML = fsplResultindB.toFixed(2) + " dB";

    // Show results section
    document.getElementById("results").style.display = "block";

    // Scroll to results
    document.getElementById("results").scrollIntoView({ behavior: 'smooth', block: 'start' });
}

// Add enter key support for all input fields
document.addEventListener('DOMContentLoaded', function() {
    const inputs = ['distance', 'frequency', 'txGain', 'rxGain'];
    inputs.forEach(function(id) {
        document.getElementById(id).addEventListener('keypress', function(e) {
            if (e.key === 'Enter') {
                freeSpacePathLoss();
            }
        });
    });

    // Auto-focus first input field
    document.getElementById('distance').focus();
});
</script>