一种低截获水声遥控信号的设计方法及性能分析

提出了一种基于时频扩展技术的低截获水声遥控信号设计方法,分别采用多载波技术和直序扩频技术实现水声遥控信号的扩时调制和频谱扩展。分析了信号的时宽带宽对低截获性能的影响,采用Wigner-Ville分布对时频扩展前后信号的能量分布进行了对比研究,利用可检测距离的概念定量分析了信号时频扩展前后的低截获性能。理论分析和仿真结果表明,该时频扩展信号具有低的瞬时功率及谱密度,处理增益大,可检测距离小,能够高可靠地实现信息的隐蔽传输。

The design and performance analysis of a low intercept probability signal for underwater acoustic remote control

A low probability of intercept （LPI） signal for underwater acoustic remote control, which is obtained by utilizing time-frequency spreading technique, is proposed in this paper. Both the Multi-carrier technique for time spreading modulation and the direct sequence spreading spectrum technique （DSSS） are used in the signal design. The relationship between Time-Band width and LPI performance is analyzed, and the comparisons of the energy distribution between original signal and modulated signal are also made. The concept of detectable distance is applied to quantify- ing the LPI performance. Theoretical analysis and computer simulation indicate that this LPI signal has advantages in lower instantaneous power and spectral density, higher processing gain, and closer detectable distance, and so it can be used reliably to achieve the information transmission with a low probability of intercept.