In order to achieve low-cost, long-distance high-precision distributed temperature measurement and improve the cost-effectiveness of the Raman distributed temperature sensor(RDTS) system, a novel Raman distributed temperature sensor based on chirp pulse compression technique using intensity-modulated is proposed. The system structure and corresponding signal modulation and demodulation methods are described, and the performance of the system is verified by experiments. The experimental results show that the new RDTS system achieves 1.6 m spatial resolution and 1.8 ℃ temperature resolution at 35 km sensing distance, which solves the problem of mutual restriction between spatial resolution and temperature resolution in traditional RDTS system.工作。