low-frequency modulation

例句：

1. 1. The radio signal was low-frequency modulated to prevent interference.
   无线电信号被低频调制以防止干扰。
2. 2. In the digital domain, low-frequency modulation is used for data transmission.
   在数字领域，低频调制用于数据传输。
3. 3.The new technology uses low-frequency modulation to enhance communication efficiency.
   新技术使用低频调制来提高通信效率。