航空正交水平磁偶源频率倾子响应规律研究

随着无人机、卫星导航及微电子技术的发展,航空电磁法勘探成为可能.但是,电磁干扰制约了航空电磁法勘探的发展,为此,提出了航空正交水平磁偶源频率倾子测深法.为了论证该方法的可行性,首先,从有源频率域麦克斯韦方程组出发,利用场的叠加原理,推导了航空正交水平磁偶源水平磁场和垂直磁场的表达式,并构建了张量频率倾子;然后,采用数字...

Response rules of airborne orthogonal horizontal magnetic dipole source frequency-tipper sounding method

With the development of UAV,satellite navigation and microelectronics technology,airborne electromagnetic exploration is possible,but electromagnetic interference restricts the development of airborne electromagnetic method.Therefore,this paper proposes an airborne orthogonal horizontal magnetic dipole source frequency-tipper sounding method.In order to demonstrate the feasibility of the method,the expressions of horizontal magnetic field and vertical magnetic field of airborne orthogonal horizontal magnetic dipole source are derived by using the superposition principle of field from the Maxwell equations in active frequency domain,and the tensor frequency-tipper is constructed.Then,the digital filtering technique is used to calculate the imaginary part of tensor frequency-tripper response of homogeneous geodetic medium.By contrast and analysis,the spatial distribution rules of the tensor frequency-tipper with airborne method are the same as the ground method.The imaginary amplitude IFT_x and IFT_y have the characteristics of near,transition and far regions.Then,the effects of the variation of earth resistance,flight altitude and reception and emission distance parameters on the imaginary part of tensor frequency-tipper are calculated respectively.The whole region analysis shows that the response in the far region is linear,and the transition and the near regions show a complex functional relationship.Finally,the imaginary part of the frequency-tipper response of the typical layered medium in the far region is calculated.The calculation results show that the imaginary part of tensor frequency-tipper can reflect the electrical structure of the typical layered medium like the geometric resistance method.In a word,the imaginary part of tensor frequency-tipper in the far region is expected to solve the technical bottleneck of airborne electromagnetic exploration.