spread-spectrum remote control

例句：

1. 1. The spread-spectrum signal is difficult to detect.
   这种频谱信号很难被检测到。
2. 2. The spread-spectrum technology is widely used in military communications.
   这种频谱技术在军事通信中被广泛使用。
3. 3. The spread-spectrum system can provide secure communication over long distances.
   这种频谱系统可以在长距离上提供安全的通信。