A nonmagnetized collisional plasma parameter estimator from two frequency signal interrogation attenuation is developed. The plasma parameters that are estimated are the plasma frequency, electron neutral momentum collision frequency, and the plasma thickness. The plasma frequency and electron neutral momentum collision frequency are considered uniform across the plasma thickness. The relative permittivity is defined, and the complex index of refraction is developed. Using this definition and applying the plasma frequency, electron neutral momentum collision frequency, the radial propagation frequency, and plasma thickness, an attenuation is determined for known cases. The development of the estimator is discussed. The estimator uses a performance index where the minimum difference between the plasma frequencies and electron neutral momentum collision frequencies is determined for the two signal interrogation frequencies under the constraint of the same plasma thickness. The estimator was developed in three stages which include iterative, sequential, and adaptive. The setups of the iterative, sequential, and adaptive approaches are discussed. The impact of the interrogation frequency and the estimator setup is investigated. The estimator in the three development stages is compared with known cases and the plasma parameter estimator performance is quantified.

中文翻译：

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非磁化碰撞等离子体参数从两频信号询问衰减估计

开发了一种来自两个频率信号询问衰减的非磁化碰撞等离子体参数估计器。估计的等离子体参数是等离子体频率、电子中性动量碰撞频率和等离子体厚度。等离子体频率和电子中性动量碰撞频率在等离子体厚度上被认为是均匀的。定义了相对介电常数，并开发了复折射率。使用该定义并应用等离子体频率、电子中性动量碰撞频率、径向传播频率和等离子体厚度，确定已知情况的衰减。讨论了估计器的发展。估计器使用性能指标，其中等离子体频率和电子中性动量碰撞频率之间的最小差异是在相同等离子体厚度的约束下为两个信号询问频率确定的。估计器分三个阶段开发，包括迭代、顺序和自适应。讨论了迭代、顺序和自适应方法的设置。调查了询问频率和估计器设置的影响。将三个开发阶段的估计器与已知案例进行比较，并量化等离子体参数估计器的性能。顺序的，自适应的。讨论了迭代、顺序和自适应方法的设置。调查了询问频率和估计器设置的影响。将三个开发阶段的估计器与已知案例进行比较，并量化等离子体参数估计器的性能。顺序的，自适应的。讨论了迭代、顺序和自适应方法的设置。调查了询问频率和估计器设置的影响。将三个开发阶段的估计器与已知案例进行比较，并量化等离子体参数估计器的性能。