Then the inverse problem from the scattering parameters to the constitutive parameters is analyzed and a method is developed , including some relevant formulae . ambiguities associated with the inverse problem are discussed and a time - domain technique is given to remove them 从得到的场解出发,又推导出平板材料的s参量的表达式,并据此讨论了求解材料微波参数的问题,提出了一套完整的求解方案以及相应的求解公式。