【作者】 张晓丰；

【导师】 昂志敏；

【作者基本信息】 合肥工业大学 ， 电路与系统， 2004， 硕士

【摘要】 海杂波的建模与仿真是雷达目标模拟中环境模拟的重要部分。仿真得到的海杂波数据良好与否是雷达最优化设计及雷达信号处理的关键。对海杂波的研究迄今已有50多年，但其实验数据和理论远不能令人满意，还不可能对海面回波的电平(作为雷达参数和海面状态参数的函数)做出高度准确的预测。对雷达波来说，海面是极其复杂的反射体，关键是找出一些合适的参数，以便建立一个描述海浪一回波依从关系的数学模型。 本文在海杂波统计特性的基础上，通过详细分析雷达波长、海情、入射余角以及极化方式对海杂波特性的影响，得出近海距离、严重杂波情况下的海杂波信号特性，然后在现有雷达地杂波设备的基础上，分别采用零记忆非线性变换法及基于独立采样的方法对海杂波进行建模与仿真，并比较了两种方法得到的仿真信号的特性。对仿真信号的特性验证表明：产生的海杂波数据能够很好的满足幅度分布特性和谱特性要求。仿真结果与和理论模型的结论符合较好，说明用这两种方法产生海杂波信号是可行的。通过对多次的实验数据进行比较发现：相比于零记忆非线性变换(ZMNL)法，基于独立采样的方法得到的仿真数据在功率谱特性方面更为稳定。 仿真得到的数据可以作为产生多重独立杂波的信号输入。叠加热噪声信号和目标回波信号后对射频信号进行调制即得完整的检波前的雷达海面回波信号。更多还原

【Abstract】 The performance of microwave radars operating over the sea is often limited by unwanted returns(sea clutter) from the sea surface. The properties of microwave sea echo have consequently been the subject of a large number of investigations since the second world war, but the experimental data doesn’t accord with the theory perfectly.The modeling and simulation of sea clutter is very important in radar system simulation. The data obtained from simulation is the key of radar signal processing and optimization of radar system design.Progress, though steady, has been slowly, due largely to difficulties inherent in attempts to characterize a random natural phenomenon in terms of a limited set of parameters. For many years, various non-Gaussian probability distributions have been offered as models for the amplitude of sea clutter. This paper contains a useful smmary of log normal distribution, weibull distribution and the K-distribution. The weibull distribution may well extend to phenomena other than radar including radiation scattered from turbulent or rough surface. The modeling and simulating of sea clutter (weibull distribution) with its parameters and ranges of applicability is introduced in this paper. The generated signal can be used in the simulation of the Radar system.更多还原