Quantum sensors are known for their high sensitivity in sensing applications. However, this sensitivity often comes with severe restrictions on other parameters which are also important. Examples are that in measurements of arbitrary signals, limitation in linear dynamic range could introduce distortions in magnitude and phase of the signal. High frequency resolution is another important feature for reconstructing unknown signals. Here, we demonstrate a distortion-free quantum sensing protocol that combines a quantum phase-sensitive detection with heterodyne readout. We present theoretical and experimental investigations using nitrogen-vacancy centers in diamond, showing the capability of reconstructing audio frequency signals with an extended linear dynamic range and high frequency resolution. Melody and speech based signals are used for demonstrating the features. The methods could broaden the horizon for quantum sensors towards applications, e.g. telecommunication in challenging environment, where low-distortion measurements are required at multiple frequency bands within a limited volume.

量子传感器以其在传感应用中的高灵敏度而闻名。然而，这种敏感性通常伴随着对其他​​同样重要的参数的严格限制。例如，在测量任意信号时，线性动态范围的限制可能会导致信号幅度和相位的失真。高频分辨率是重构未知信号的另一个重要特征。在这里，我们展示了一种无失真的量子传感协议，该协议将量子相敏检测与外差读出相结合。我们使用金刚石中的氮空位中心进行理论和实验研究，展示了重建具有扩展线性动态范围和高频率分辨率的音频信号的能力。基于旋律和语音的信号用于展示这些特征。这些方法可以拓宽量子传感器的应用范围，例如在具有挑战性的环境中进行电信，在这种环境中，需要在有限体积内的多个频段进行低失真测量。